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987.2 Cayman S MT Track Prep, Maintenance, and Mods

63K views 366 replies 32 participants last post by  GLTHFJ60 
#1 · (Edited)
Hey everyone!

I recently purchased this 2009 Cayman S with the 6 speed manual off BAT. I haven't actually picked up the car yet (will do later this week) but I am already digging through the forums here looking for the information I need, and so far it has been very helpful. This thread I'm using to document what I'm going through with my car, as well as clarifying anything I'm still unsure about. For now, my plan for the car is to take it to open track days here in California and start building up my experience on the track. Over time (when budget allows) I'll modify the car to suit this purpose. I also plan on using it for weekend driving, still, so currently I'm not considering stripping it out and going full bore with it.

Right now, I'm compiling the "bare minimum" that I need to do to the car to make it reliable and usable at the track, including maintenance and mods.

This car has ~70K miles on it, and has supposedly been serviced based on the recommended Porsche intervals. The 60K maintenance was completed, and it has has a new OEM clutch as well. Based on this, it seems to me that the main maintenance item I want to take care of prior to taking it to the track is doing a transmission fluid change. As with everything, there seems to be a lot of back and forth on what fluid to use - I'm still trying to decide between the main 3 people suggest, Redline 75W-90NS, Mobil 1 Delvac 75W-90, and OEM fluid. Since I plan on using this car primarily for the track, I'm looking for the fluid that will best protect under heavy loads and heat, even if it means forgoing easier shifting when cold. Input welcome on this one.

Are the water pumps a concern on the 9A1? Any other maintenance items I missed or things I should check?

Onto the modifications - as I'm sure you all know, the consensus is that the LCAs are the first thing that need to be done to be able to setup proper track suspension geometry. I've been looking into pricing out the 996 GT3 LCAs (99634112190 and 99634112290), but it seems like the inner pieces (99634144190) are way more expensive than they used to be ($250+ ea). If I go this route it seems like getting a monoball inner is the way to go. Also looking into the aftermarket LCAs like the ones from RSS and Tarett. Seems like 20mm worth of spacers (including the litronic bracket spacer) is what I'll need. If anyone has a hookup on pricing, let me know.

Now, for brakes. Everyone seems to go with the GT3 front brake duct swap, so I'm going to grab those (99734148492 and 99734148392). I'll be doing a full flush with a high-temp fluid, and when I get the car I'll inspect the rotors to see if they have enough life left and not too much stress cracking. Brake pad choice is another one where there is no consensus (unsuprisingly) but it seems the two common choices are from PFC and Pagid. I also see a split in people that swap pads for track days, some say you'll lose performance doing that, some say it's just fine. Looking for your input and experience on this one.

I plan on trying to find a second set of 987 S 18" wheels so I can run some stickier tires and swap back to the PS4S on the street. If anyone has some at a reasonable price (especially if you're local, Northern California) let me know. Or if someone is selling any of the below items feel free to reach out.



Mod list update 11/26/20


Maintenance:

Transmission Fluid - Redline 75W-90NS
Coolant Flush - Pentosin Pentofrost++
Castrol SRF Brake Fluid
Track alignment, current specs: -2.8* F -2.3* R camber, 8.7* front caster, 0 toe front, .15 toe in rear (each side)
Ride height (hub to fender): 350mm front, 360mm rear
Rented durametric: Removed airbag light for driver's seat/passenger AWS, disabled TPMS, side markers as turn signals, comfort windows

Completed Mods:
"eBay" Short Shifter
Numeric Shifter Cable
RSS Front LCAs
Ohlins R&T coilovers
GT3 adjustable front swaybar, Tarett front drop link
Tarett GT rear swaybar, SPL drop link
Stomski Racing tie rods
Torque Solution toe links
Tarett Toe link lock plates
Ferodo DS1.11 brake pads (F/R)
Sebro Slotted Rotors (F/R)
GT3 front brake ducts
Center radiator
Apex Racing EC-7R wheels w/ Nitto NT-01
Technoversions brace
Race headers
OMP WRC-R Seat
GT2 extended seatbelt buckle
Brey Krause slider adapters
Top Gear valved exhaust
Function First "Soft" 60A engine mount insert w/ new OEM mount
Function First Transmission Mount Upgrade


Mod wishlist short-term:
Wheel studs
Tow hook
Rear Brake Ducts?

Mod wishlist long-term:
GT3 Master Cyl?
Rear LCAs
Other bushing/mount replacements?
Tune?


Let me know if I missed anything you think is essential Otherwise, input is welcome on anything, including recommendations on future mods, brands, etc. Hope to see a few of you out there on the track!
 
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#39 · (Edited)
Hyrax, you are going down the slippery slope now. preloading the Ohlins help in compression then droop phase, where the car's front wheels are unweighted. The preload will prevent the springs from becoming slack on the droop phase. It sort of takes the place of helper springs on other setups. My shop did this to their Ohlin installations. It does take away about 2 mm of threads on the outside of the shock body. Even with that 4 mm of preload, down the road about 3 years, the springs settle and I can still rotate my f springs when I change my tires after an event. This is a good thing as you will need as much spring travel in front to absorb the bumps in the daily drive mode.

The camber difference between f and r is different on my car due to using 255/35/18 f, so I can use a little more negative camber in the rear past the magic -.5 camber number difference. I find that running with this setup allows a little more throttle induced rotation mid corner, which allows for 4 wheel drifting in some corners with full power down. That is 295+ power, which is not enough to break lose the 275/35/18's RE71R's on the rear. I suspect that if I had the clearance under my skid plate to use 285/30/18 RE71R's, I would be asking for the same or even more camber in the rear than the front as Lovetoturn does with his 981 using that combo. I am currently using -2.7f and-2.5r camber. Car balance is very important to me, that is why I have this setup with my S motor torque curve. More power would require a bigger tire in the rear or a LSD, but so far the RE71R's are well balanced. I will soon see how the car reacts to new Hoosier A-7's being used at the next track event in a couple of weeks. They are the same size as my other tires.

Another way of looking at this setup is the actual front and rear outside tire shoulder roll. On RE71R's there are small triangles located high on the sidewall of the tire shoulder near the cap that you can use a measurement tools. I use these a guidelines for tire pressures and you would be surprised on how low you can go with RE71R's and still have great control of mid corner traction without pulling the tires off the rims, like 25 lbs and still does not hit the triangles. This use is for a wet cold track. I would certainly not recommend running lower pressures to anyone using Michelin P4S's or even Pilot sport cup 2 tires. They have too soft of side walls for this application.

Your home wrenching does present some alignment issues. Some guys actually have great success with string to get close to 0 toe in front. Rear is going to be a problem without adjustable toe links. Simply not enough adjustment available using the OEM adjuster to get the correct toe in with a dropped Ohlin car. Especially if you have had it corner balanced, which I highly recommend so that your turnin cross weight shift is the same both directions (add the front right weight to the left rear and match it to the left front to the right rear). Your shop will try to get these percent numbers to be as close as possible. This is where the benefit of changing the ride height on each corner really comes in handy. Some cars are nearly perfect, while others not so much.

Your springs will settle and change the calculations over a month or so. I did not have that time line to play with so they installed the Ohlins and did the corner balance. I also did not have the adjustable rear toe links to complete the job in the first place which left me with -2.2 rear camber. So 6 months later, I had the shop do the job correctly with the adj toe links, which included a hammer to the right rear sub frame perch, which was installed incorrectly at the factory. The hammer and the adjustable toe links did their work, allowing the 12 minutes of toe in in the rear with -2.5 camber. I also had the shop do a bumpsteer adjustment on all 4 corners. I was not present when they did this so not sure how accurate their method was, but just looking at the washers above and below the outer ball joint of the rear toe link, I can see they are different.

Changing the ride height does change the camber. Also you might want to address the rake angle of your car to assure you do have a little rake front to back. Not too much. I like my car setup to almost 0 rake. Since I do not have a LSD, I need a little more rear weight over the tires. The trade off is threshold braking becoming less stable from rear wobble if done with too much rake and understeer if not enough rake.

Good suspension work is like an artist and his painting where small details all add up to a great result.
 
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#40 · (Edited)
Hyrax, you are going down the slipperly slope now. preloading the Ohlins help in compression then droop phase, where the car's front wheels are unweighted. The preload will prevent the springs from becoming slack on the droop phase. It sort of takes the place of helper springs on other setups. My shop did this to their Ohlin installations. It does take away about 2 mm of threads on the outside of the shock body. Even with that 4 mm of preload, down the raod about 3 years, I can still rotate the front springs when I change my tires after an event.
Oh I know it, haha. I understand what the preload is for, I'm more wondering what actual benefit you get from 4mm vs 2mm. If 2mm prevents the slack then why do 4mm.

The camber difference between f and r is different on my car due to using 255/35/18 f, so I can use a little more negative camber in the rear past the magic -.5 camber number difference. I find that running with this setup allows a little more throttle induced rotation mid corner, which allows for 4 wheel drifting in some corners with full power down. That is 295+ power, which is not enough to break lose the 275/35/18's RE71R's on the rear. I suspect that if I had the clearance under my skid plate to use 285/30/18 RE71R's, I would be asking for the same or even more camber in the rear than the front as Lovetoturn does with his 981 using that combo. I am currently useing -2.7f and-2.5r camber. Car balance is very important to me, that is why I have this setup with my S motor torque curve. More power would require a bigger tire in the rear or a LSD, but so far the RE71R's are well balanced. I will soon see how the car reacts to new Hoosier A-7's being used at the next track event in a couple of weeks. They are the same dementions as my other tires.
It definitely sounds like you have it setup very well. The difference in camber makes sense with your configuration as I suspected. I'll just have to get mine done as best I can with the parts I have installed now. The mods and changes will continue down the road. Like you said, slippery slope haha.

Your home wrenching does present some alignment issues. Some guys actually have great sucess with string to get close to 0 toe in front. Rear is going to be a problem without adjustable toe links. Simply not enough adjustment available using the OEM adjuster to get the correct toe in with a dropped Ohlin car. Especially if you have had it corner balanced, which I highly recommend so that your turnin cross weight shift is the same both directions (add the front right weight to the left rear and match it to the left front to the right rear). Your shop will try to get these precent numbers to be as close as possible. This is where the benefit of changing the ride height on each corner really comes in handy. Some cars are nearly perfect, while others not so much.
I did try to get the outer tie rod loose to so a rough adjustment myself but didn't have any luck (though I was tired and didn't try too hard). I've had good luck with using AAA for situations like this. Getting my money's worth!

So you think I won't be able to get the rear toe right with the car lowered on the Ohlins and setup for say, -2.2R camber? Is it the lowering that causes the inability to adjust it enough?

Your spings will settle and change the calculations over a month or so. I did not have that time line to play with so they installed the Ohlins and did the corner balance. I also did not have the adjustable rear toe links to complete the job in the first place which left me with -2.2 rear camber. So 6 months later, I had the shop do the job correctly with the adj toe links, which included a hammer to the right rear sub frame perch, which was installed incorrectly at the factory. The hammer and the adjustable toe links did their work, allowing the 12 minutes of toe in in the rear with -2.5 camber. I also had the shop do a bumpsteer adjustment on all 4 corners. I was not present when they did this so not sure how accurate their method was, but just looking at the washers above and below the outer ball joint of the rear toe link, I can see they are different.
Seems like based on this I might be able to get -2.7F and -2.2R camber with proper rear toe. I'd be happy with that for now.

Corner balance is definitely something I want to do. Did you not have to re-balance once things settled down, though? And wouldn't that throw off the alignment a bit once it settles?

Changing the ride height does change the camber. Also you might want to address the rake angle of your car to assure you do have a little rake front to back. Not too much. I like my car setup to almost 0 rake. Since I do not have a LSD, I need a little more rear weight over the tires. The trade off is threshold braking becoming less stable from rear wobble if gone too much rake and understeer if not enough rake.
About how much rake would you suggest?

Also, now that I have the adjustable caster pucks, do you have a suggestion for that spec as well? Some people say max it out, others say don't...


Edit: and side note, my damn roof liner is falling off now ? I guess I need to look into reupholstering that.
 
#41 · (Edited)
Hello,
As the company that has programmed the Interseries cars, Winning Daytona, World Challenge and others the suspension and adjustments are very crucial. This is also along with your training or track experience. One thing you could also consider is the tuning of the car. Your at 320BHP and Softronic was at 360BHP back in 2009 after the release in 2008 and use 93octane or better. The World Challenge cars are at 390BHP yet require 100 octane and are basically full race. We had been asked how could you get 360BHP out of the 3,4DFI back in 2009.... Its simple as Porsche tunes cars as they want to market their engines etc for years after. The 991 3.4 was at 350BHP so maybe now it makes more sense ,310BHP in the 3.4 BoxsterS to 345BHP as it was in the software. Yes there was air filter changes and intake routing yet this was not specific to the increase as in 2009 was sufficient to generate 480BHP in the 3.8X51 when transplanted and tuned correctly for racing.

This opens up to another subject about bolt ons and simple engineering ......

Best,
Scott
 
#42 ·
I set my front toe as close as I could get it to 0 today so the car is now driveble. Based on Apex1's "street setting" recommendation of 12 clicks out I set off for my first test drive. I was honestly very surprised. The car genuinely feels more compliant and supple on the bumpier roads around here. A tad more bouncy but I'm very happy based on my first short drive. Can't wait to get a proper alignment done so I can really get into it.

The exhaust with just the competition headers installed is quieter than I expected (probably a good thing). The stock mufflers do their job well. It is noticably louder and the tone is much improved, though. I'm pretty happy with them. A valved muffler system is definitely in the eventual future, though. Oh, and no check engine light! The relatively cheap "defoulers" I found are working so far.


This opens up to another subject about bolt ons and simple engineering ......

Best,
Scott
Thanks for the info Scott. I plan to own this car for a while so I'm sure I'll come back around to tuning at some point. Suspension, brakes and such are taking priority for now.
 
#43 ·
I changed my transmission fluid yesterday evening, it's really a very easy DIY job. I went with 3 qts of Red Line 75w90ns. I had a bit of standard RL 75w90 from another vehicle that I used to supplement the final .2 qts.

If you are interested in the cheapest and easiest way to get your new fluid into the transmission, run down to your local Walmart and pick up a 1-gallon sprayer for about $5. Remove the tip, fill it up with your fluid, pressurize, and go! I zip tied the trigger down and I was full in a couple minutes hands free. Easiest transmission fluid change I've ever done!
 

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#52 ·
I changed my transmission fluid yesterday evening, it's really a very easy DIY job. I went with 3 qts of Red Line 75w90ns. I had a bit of standard RL 75w90 from another vehicle that I used to supplement the final .2 qts
I'm about to do the same job on my 987.2 boxster S and have not been able to fine good directions to go by, would you mind providing a few details about the manual transmission fluid change you did?

It looks like the suspension brace removal for the 987.2 should be the same as the 987.1 so I assume you need to have the rear wheels at full droop to not affect your alignment?

Are the drain and fill holes in the same place as 987.1s have pictured or are they in different locations?

What torx head or Allen key size did you use?

Did you fill up to the fill hole, or 3mm below the fill hole?

Any torque specs different for the plugs on a 987.2?

Did you replace the washers on the plugs or reuse them?

Thank you for any help you can offer.
 
#45 · (Edited)
I had my suspension redone 6 months down the road, to include the Elephant toe links, slightly more front camber, and the alignment. In the rear, lowered Caymans do have an alignment issue with toe in adjustments. That is the reason for the adjustable toe link and a lock out plate for the OEM toe adjuster. Simply not enough twist to push out the OEM toe link for 12 to 14 minutes of toe in in the rear when sitting level at a lowered ride height. If you have a solid thrust puck with caster setting (8.5-9.0) and wheelbase adjuster in the rear, the solid puck helps control the toe in and out to a small degree, but it also helps control forward and aft motion of almost 3 inches at the rear wheels according to my installer.

That camber alignment should do you well. You can then build your tire footprint around those camber adjustments to refine the f to r roll balance. I now use 255/35/18's f and 275/35/18 in the rear on all three sets of wheels and tires. Michelin PS4's, RE71R's and Hoosier A7's.
 
#46 ·
Just completed the install of a 3rd radiator in my 987.2 just in time for Porsche Fest in 2 weeks at Summit Point. This thread prompted me to do it. It's not difficult as there are many you tube videos showing the install. I ordered the OEM radiator and suggest assembling it including the rubber air duct before attaching it to the car. CaymanRegister has a good write up by GreenFrog https://www.caymanregister.org/showthread.php?t=34871 and this is the video I followed https://youtu.be/whBfFRNwLmc

I took the advice of GreenFrog and my mechanic to drain all coolant. Refilled it with Pentofrost E (8113106) and a UView 550000 Airlift Cooling System Leak Checker and Airlock Purge Tool Kit. I picked up six 1.5L bottles of coolant from NAPA and diluted 1:1 with distilled H2O. After burping I had about 800ml of the 1:1 mix left over. The kit from Suncoast (PK987C2RAD) had extra hardware (bolts and clips) and wasted time trying to sort it out. I should have listed to the YT video more closely as extra hardware is mentioned (faint audio in the video). The video shows the removal of the fixing plate (98750571900) by threading a screw into it and yanking it. I used a hook and pushed from the other side with my hand. Not difficult. The hardest part of the job was screwing in the screw behind the side markers. One last learning is to make sure that when reattaching the bumper that the rubber duct on the radiator mates properly with the center air intake duct in the bumper. To monitor temps get an OBDII scanner.
 
#48 ·
Just completed the install of a 3rd radiator in my 987.2 just in time for Porsche Fest in 2 weeks at Summit Point. This thread prompted me to do it. It's not difficult as there are many you tube videos showing the install. I ordered the OEM radiator and suggest assembling it including the rubber air duct before attaching it to the car. CaymanRegister has a good write up by GreenFrog https://www.caymanregister.org/showthread.php?t=34871 and this is the video I followed https://youtu.be/whBfFRNwLmc
Thank you for all of the great information on the install. I will definitely be doing this mod in the future so I'll be referring back to it.

I had my suspension redone 6 months down the road, to include the Elephant toe links, slightly more front camber, and the alignment. In the rear, lowered Caymans do have an alignment issue with toe in adjustments. That is the reason for the adjustable toe link and a lock out plate for the OEM toe adjuster. Simply not enough twist to push out the OEM toe link for 12 to 14 minutes of toe in in the rear when sitting level at a lowered ride height. If you have a solid thrust puck with caster and wheelbase adjuster in the rear, the solid puck helps control the toe in and out to a small degree, but it also helps control forward and aft motion of almost 3 inches at the rear wheels according to my installer.

That camber alighment should do you well. You can then build your tire footprint around those camber adjustments to refine the f to r roll balance. I now use 255/35/18's f and 275/35/18 in the rear on all thee sets of wheels and tires. Michelin PS4's, RE71R's and Hoosier A7's.
Thanks again for your endless help in this thread. I'll find out tomorrow to what extent we can perfect my alignment specs with my current setup. A neighbor of mine works at a local Mercedes dealership and offered to let me bring my car in and we'll do the alignment on their equipment.

Hyrax- Just looked at my OEM wheels that I reinstalled today with 18 mm spacers in f and 23 mm spacers in the rear. Looks teriffic and even fits without rubbing. The key here is using 35 sidewalls, not 40 or 45, which are harder to fit under the fender arches. So, that is the grouping I would suggest you order, rather than 10mm f and 18 mm r spacers from a previous post. Much more aggessive with OEM 57 offset 8 in f and 43 offset and 9 in r wheels.

You can certainly change the Ohlin setting of 12 clicks from stiff, to your own liking. I just gave you a starting point that I find works for my setup on the street.
Good info about the spacers, I was thinking about them the other day actually. I definitely will start playing with the settings soon, I set it to 12 to see what comfort level that provided and I was very happy with it.


I just went around and measured my car and I did a damn good job of setting my initial ride height, apparently! Here are some measurements and data in case it helps anyone in the future. All of these numbers are measured from the center of the wheel to the fender lip. I just used a tape measure for this part and it is not perfectly accurate, but close enough.


Initial measurements (stock suspension non-PASM):
FL - 14 12/16 in
FR -14 12/16 in
RL - 15 6/16 in
RR - 15 6/16 in

Current measurements (Ohlins, taken after ~90mi of driving):
FL - 13 10/16 in
FR - 13 10/16 in
RL - 14 5/16 in
RR - 14 5/16 in

I set the Ohlins up to their exact recommended specifications in the instructions. 2mm of preload, 59mm of space between the lock ring and height ring in the front, 105mm of space in the rear. I used a Bosch laser measure to set these. In hindsight, I also should have used this to measure the height of the car initially.

According to Ohlins, this should have lowered the car ~20mm all around compared to the original suspension. I ended up with ~28.5mm drop in the front, and ~27mm drop in the rear. I am very glad, at least, that my side to side numbers are even. I am also pretty close to the 30mm drop you recommended, Apex1.

Do you happen to know the difference in height F to R you have for rake? I think that, going forward, I am going to adjust height by using my laser measure from level ground to the highest point in each fender well. I should be able to get it pretty even that way and adjust rake. Eventually I will take it somewhere to get corner balanced.
 
#47 · (Edited)
Hyrax- Just looked at my OEM wheels that I reinstalled today with 18 mm spacers in f and 23 mm spacers in the rear. Looks terrific and even fits without rubbing. The key here is using 35 sidewalls, not 40 or 45, which are harder to fit under the fender arches. So, that is the grouping I would suggest you order, rather than 10mm f and 18 mm r spacers from a previous post. Much more aggressive with OEM 57 offset 8 in f and 43 offset and 9 in r wheels.

You can certainly change the Ohlin setting of 12 clicks from stiff, to your own liking. I just gave you a starting point. Try using 12 f and 14 r clicks from stiff on the Ohlins. The difference f to r is due to shorter front springs with 400 lbs/in. You need a little more compression/rebound valve settings to keep them compliant yet have the full range of spring travel for your daily work. I used 3f and 8r in my last autocross event and found the rear sagging or nose raising out of the corners with my Hoosier A7's. I should have used 5f and 7r to accomplish what I needed at that event. My follow up event proved that is the correct settings for a relative smooth track. Maybe 4 and 6 might work, but I want a little compliance in my ride.

From a Rennlist autocross competition thread from Sturgus about setup of 987, he uses a calculation with the wt of the car over the f and r wheels, also the polar motion and the engine position to determine the correct spring rates should be 350 lbs/in f and 510 lbs/in r. This means that the Ohlins are slightly oversprung in f and undersprung in the rear thus the two different golden knob adjustments f to r by 2 clicks. So, back to your description of how the initial 12 click from stiff setting felt to you, a little bouncy. So just 2 clicks stiffer in front to 10 and leave the r's at 12 should give you a compliant ride without the bouncy motion.
 
#56 ·
Hyrax- Just looked at my OEM wheels that I reinstalled today with 18 mm spacers in f and 23 mm spacers in the rear. Looks teriffic and even fits without rubbing. The key here is using 35 sidewalls, not 40 or 45, which are harder to fit under the fender arches. So, that is the grouping I would suggest you order, rather than 10mm f and 18 mm r spacers from a previous post. Much more aggessive with OEM 57 offset 8 in f and 43 offset and 9 in r wheels.
Apex, did you go with extended wheel bolts, and from where? They seem to be pretty expensive, seems like studs should be a lot cheaper.
 
#49 ·
More data and I standardized how I am measuring ride height from the ground using my laser measure. I center my laser measure with the center of the wheel and set it on the ground. I take the fender measurement from directly above that location using a straight edge with a level on top. I realize because of wheel/tire differences, pressure, and wear this is really not an accurate figure for others to compare against but is useful for my own approximate adjustments. Here is how it came out:

FL - .651m
FR - .654m
RL - .678m
RR - .678m

Pretty consistent and this measurement should be more accurate compared to eyeballing with a tape measure.

Below are my rake measurements (these are based on the center wheel to fender measurements of the post above).

Percentage of height
Stock: 14.75/15.375 = .959
Current 13.625/14.3125 = .952

Actual rake F to R
Stock: 15.875mm
Current: 17.4625mm

Apex1, I found a post of yours from 09/26/17 while reading up on this subject. At the time you measured F340mm R355mm from center of hub to fender, a 15mm difference.
 
#50 · (Edited)
I find that with a little less rake, I have more forward bite out of the corners. My setup now is 325mm f and 340mm r. Still 15mm difference, so the spring sag was equal front and rear from the initial setup. I will have the car re aligned in a couple of months to include -3.0 camber f and -2.5 r. I will also have them check the corner balance again to make sure each corner sag was about the same and reduce the rake/ride height 5 mm in the rear for a 10 mm difference, provided the rear golden knob is still accessible to turn with my thumb. Attached is a picture of 18mm and 23mm spacers with OEM wheels and Michelin MP4S 255/35/18 f and 275/35/18 r.

This is another role for the Cayman, which it does very well. Pic's 3&4 show track wheels and Hoosier A-7's. Pic's 5&6 show Signature SV-104 with RE71R's. Both Hoosiers A7's and RE71R's are 255/35/18 f and 275/35/18 R.

Land vehicle Vehicle Car Automotive design Rim
Land vehicle Vehicle Car Motor vehicle Automotive design
Land vehicle Vehicle Car Automotive design Motor vehicle
Land vehicle Vehicle Car Automotive design Sports car
Land vehicle Vehicle Car Rim Sports car
Land vehicle Vehicle Car Rim Alloy wheel
 
#51 ·
I find that with a little less rake, I have more bit out of the corners. My setup now is 325mm f and 340mm r. Still 15mm difference, so the spring sag was equal front and rear. I will have the car re aligned in a couple of months to include -3.0 camber f and -2.6 r. I will also have them check the corner balance again to make sure each corner sag was about the same and reduce the rake/ride height 5 mm in the rear for a 10 mm difference. Attached is a picture of 18mm and 23mm spacers with OEM wheels and Michelin MP4S 255/35/18 f and 275/35/18 r.

This is another role for the Cayman, which it does very well.
Looks beautiful!

I got my initial alignment done today. Not perfect but enough to not destroy my tires haha.

I discovered not enough shims came with my kit to get me anywhere near -2.7. I got to -2.25 in the front and -2.2 in the rear so I am pretty even all around for now. -12 toe in the rear, 0 out front.

Those caster pucks are a pain in the *** to adjust. I also apparently overtorqued one side so I am going to have to order a new bolt and nut and redo it. If anyone has recommendations on the easiest way to adjust those I'm all ears...

How do you go about measuring your ride height out of curiosity? Like what tools and method.

I am going to do some driving and let things settle. I'll adjust ride height and get it where I want it. Then I'll order and add more shims and get the alignment set nicely for my first track day in the Cayman (hopefully next month).
 
#57 · (Edited)
ECS sells the spacers and correct length bolts as a kit. I like the clean look of bolts rather than bare threaded studs sticking out.
 
#60 ·
I like studs for ease of wheel swaps...
Studs are definitely easier I think haha. We'll see I'm going to look back into it later. I spent my spacer budget on a new center radiator...

I just installed a front tower brace. I certainly can feel the positive effects, as my car is more planted in downhill corners, turnin and braking in front. Racing Dynamics, $165.00 plus shipping.

Hyrax- you can think of this front brace as the counter to the Pedro's TechnoBrace to help control the rear frame rails. I think the Schnell brace ups control factor here by having two support brackets attached to the frame rails rather than a single bolt of the Pedro's brace. Both of these braces f and r help remove torque/twist associated with road compression/rebound transmitted through the suspension parts. I found that as I increased the lateral grip by using wider wheels and stickier tires, I needed more control of the suspension attachment points shock towers/frame rails to counter the increased side torque being produced.
Looks like a great mod certainly! Braces are one of the mods I'll be doing later on.

The other day I installed fresh rotors on front and rear, and Ferodo DS 1.11 pads. These things are definitely not quiet but should perform great. They have a hell of a bite and not bad when cold. Went with standard rotors for now to see how they hold up, maybe I'll upgrade to Girodiscs or something like that in the future.

I also replaced one of my Numeric cables as I was getting binding in second gear. This new cable resolved my issues and the shift is super crisp now.

I'll be out at Thunderhill West this coming Sunday. Still a lot to do before that day and it is supposed to be quite hot (100+).

In preparation for that heat I decided to take a shot on Pelican's center radiator kit. I couldn't find any confirmation that it'll fit the 987.2 but for the price I figured I'd try and fit it even if it requires a little modification. My only concern is the hoses being the wrong size. If it doesn't work I'll just take the opportunity to clean out my other radiators haha.

I also have some Castrol CSF to flush out my brake fluid with, I need to install the extra spacers for my front LCAs and do another alignment, and I need to get my ride height set correctly. Super excited to get our there, Thunderhill West, while short, looks fairly technical and fun.
 
#59 · (Edited)
I just installed a front tower brace. I certainly can feel the positive effects, as my car is more planted in downhill corners, turnin and braking in front. Racing Dynamics, $165.00 plus shipping.

Hyrax- you can think of this front brace as the counter to the Pedro's TechnoBrace to help control the rear frame rails. I think the Schnell brace ups control factor here by having two support brackets attached to the frame rails rather than a single bolt of the Pedro's brace. Both of these braces f and r help remove torque/twist associated with road compression/rebound transmitted through the suspension parts. I found that as I increased the lateral grip by using wider wheels and stickier tires, I needed more control of the suspension attachment points shock towers to keep the camber alignment in f/frame rails in r to counter the increased side torque being produced which could change the toe and camber alignment during droop/compression motion.
With this setup, I can easily 4 wheel drift out of corners onto the straightaways, using Hoosier A7's with the PSM off.
 
#63 ·
Additional LCA shims are in, alignment done, center radiator added, and all the coolant was vacuumed out and replaced.

To anyone wondering if you can just use the $200 Pelican Parts 987.1 radiator kit, the answer is mostly yes. The radiator, mounting, and rear duct are the same. The grille and front ducting are different. I'll be tossing the 987.1 stuff on eBay and I found a used 987.2 duct so it'll all work out. This was obvious once I looked at the parts diagrams but I guess I got lazy when ordering. Oh well. The bumper cover is pretty easy to remove. Here are the part #s you need along with the kit: 98757532303, 98757532303

For now, I am running no duct which is suboptimal for sure but way better than nothing with the heat I'll be dealing with this weekend. I dremeled out my original "grille" to be an opening.

Also, if you have never at least cleaned out your radiators, do it! There is likely a ton of junk in there. Not even just the leaves in the photos that were sitting in front, but the crap inside the fins and between the condenser and radiator, too. I separated them and spent probably 30 mins blowing everything out with compressed air. That should help a lot with cooling.
 

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#64 ·
Back in from Thunderhill West! Overall a very successful and fun day, but damn was it hot.

13 minutes into my first session my pedal went to the floor. It did firm up after a couple pumps. I decided to bleed all 4 calipers and quite a bit of debris (maybe rubber?) was in the fluid. Particularly in the driver's front caliper. I'm thinking this may be a symptom of a failing master cylinder seal but I'm not sure. My other guesses are seals in the calipers, or just stuff that broke loose when I compressed the pistons to install my new pads.

After doing the caliper bleeding I was good the rest of the day, though I was wary of losing brakes so I didn't go all out. Pads held up great to the temps and I didn't notice fade even after many hot laps.

PS4S did well overall but I did notice them getting overheated and greasy. 103* ambient temperature will do that I suppose. Looking forward to getting some dedicated tires.

I am definitely seeing the need for a seat that can really hold me in place. I had no complaints about the stock one until I was forced to brace myself through every corner. Not really something I wanted to install but I am considering it a lot more now.

That track is a lot of fun. Very technical and much more challenging than Buttonwillow was. I would say that I'd love to have a lower rear end ratio when coming out of some of those hairpins. Even second just didn't seem low enough, I was out of the powerband. Missing that low end torque from my Focus ST!

My best laptime of the day (according to the Racechrono app) was 1:31 and I was consistent around there as well. Kept getting quicker as the day went on even though the temps got way too high towards the end so I'm pretty happy with that. Definitely room for improvement in particular with my heel toe and carrying more speed through the hairpins. Hopefully I'll have a couple photos to share soon.
 
#65 ·
Any ideas about your suspension that needs some adjustments. Was the balance good front to rear as far as understeer/oversteer goes.
 
#66 ·
I had one moment that was completely unlike the rest of the day where I actually ended up off track. I was leaving turn 4W, was holding the steering wheel steady through the turn not making any jerky movements and was applying steady throttle. I had just barely begun to reduce my steering angle when suddenly, the rear end stepped out significantly. I countersteered, applied some throttle and straightened it out but I didn't have quite enough room since I was turning left and was headed into a right so I went off the track (luckily in a controlled fashion) and didn't damage anything. It was what I'd call snap oversteer but I am still not entirely sure what caused it. Probably a multitude of factors including the fact that my tire pressures and temps were probably not high enough yet since I was only in my second lap, I may have entered the corner a bit late and turned in a little too much. The tires squealed a little bit before letting go but were not very communicative that they were about to completely let loose. I took that same corner at higher speeds on a similar line later in the day so I am still not certain, to be honest.

I do think I am "overbraked" for these PS4S tires, I was able to engage ABS very easily (especially as they got hot/greasy) which made threshold braking a little challenging. I always drove with the PSM switched "off", though I could feel it kick in around the hairpins if I nailed it in second gear.

Overall, I think it felt very neutral with a slight oversteer bias. My alignment was 2.7* camber front, 2.2* rear, 0 toe in front, about 5 minutes in each side in the rear. Ride height as measured from the center of the wheel is (338mm F, 348mm R). I ran 5 clicks F and 7 clicks R from stiff. I'd like to get involved with a Porsche club or shop sponsored track day sometime soonish and pick the brains of racers/instructors with far more experience in setting up these cars than me. I am a little surprised still that the car bit as hard as it did when I went off track so I do wonder if something in my setup didn't exacerbate whatever small mistake(s) I made.
 
#67 · (Edited)
Maybe a case of bumpsteer causing your rear toe to get out of alignment, thus snap oversteer. Just a wild guess. Adjustable toe links with bumpsteer hard rubber washers either above/below on the monoball connector bolt attached to the upright (B)
 
#69 ·
Well, having done a lot of reading, I am still not sure what to think about bump steer and rear toe changes on this platform. The most useful threads I have come across are below and do contradict each other to an extent. I am still not sure what configuration is best. In the first article by Slatfatf, the recommendation is to come closer to leveling your toe link with your LCA. The end result being (based on my understanding) that you'd end up with toe-in on suspension compression (or bump steer) rather than any sort of toe out.

That being said, lowering my car and leaving these components as they are should have already made these two parts closers to level with each other, thus reducing the toe out effect under compression. Maybe that is the case, and I do need to measure my points as referenced in that article. Apex1, do you happen to have a photo of what the shimming that was done on the rear of your car looks like? I'm curious what direction they went with it, and how it was measured if you know.

The final link there is a response to Slatfatf's article which does resonate with me. Since the toe link is longer than the LCA, the further you get from the neutral point (or range), the more the toe will change. So, if the link/arm are set as referenced in Slatfatf's article, you'll be further towards the toe-in side of things. You'd set it at static height so that any more compression should induce only toe-in. My question is what is more important, not having any toe out upon compression, or having less overall change in toe, which would mean setting that toe arm higher rather than shimming it down.


https://www.planet-9.com/reviews/ca...bump-steer-correction-and-locking-plates.html

https://www.planet-9.com/987-cayman...ods-aka-toe-links-toe-changes.html#post299821

https://www.planet-9.com/987-cayman-and-boxster-modifications/64331-toe-link-spacing-revisited.html
 
#70 · (Edited)
Ok, now we are talking. This is where science and art become a mixed bag. I used Elephant adjustable toe links because their head angle is bent to reflect the new ride position. From their description on the Elephant web page describing how their toe link works in relation to a lowered Cayman. The bumpsteer adjustments are the thickness of washers above and below the upright attachment point for the toe link. In the P9 reference above, he used 2 washers to drop the head 5 mm which would allow the toe link and the LCA arm to be parallel on a flat floor. I had my car corner balanced which caused more issues as it sits higher on the drivers side. So, the car needed 200 lbs of wt in the driver's seat to do this calculation. Even with this done, the washers on one side were slightly different than the other by a small amount. Cantrell Motor Sports did this work on their lifter laser suspension frame rig. This allows the tech to put a level on the arms. They also attached some additional weight to the center of the rear to mimic compression. Not sure how they got the droop measurements, may be a jackstand underneath the tranny then lowered the lift about 1 inch. You need 1 inch both ways to get the center of the arc. Then they put in the washers to correct the level and measured the toe for each point, flat, droop and compression. They charged me a lot for this work I believe 2 hrs of shop time @ $160/hr. Did both front and rear. This was a couple of years ago.

So I can pound the bumpy hill climb by my house without any worries of rear steer. It can be even worse on the downhill side as the car is in droop mode, then quickly changes to forward traction out of a few tight slalom type corners. This type of action can really upset the power traction delivery, then hitting the brakes hard to lift the rear end at the same time turnin, then repeat the power on. Going fast down hill on this winding road really takes guts and a smooth transition through the arc of the rear suspension.

The following is quoted from Elephants toe link description,

Angled Head – Lower the car and the toe links angle down. This shifts the ball stud from its center and limits the available range of articulation.
We solve this problem by angling the head to move the stud back towards the center of its range of articulation at static ride height.
Bump Steer Adjustable – 986 and 987 version have built in bump steer adjustment that lets you dial in a minimal bump steer curve.
 
#71 · (Edited)
Ok, now we are talking. This is where science and art become a mixed bag. I used Elephant adjustable toe links because their head angle is bent to reflect the new ride position. From their description on the Elephant web page describing how their toe link works in relation to a lowered Cayman. The bumpsteer adjustments are the thickness of washers above and below the upright attachment point for the toe link. In the P9 reference above, he used 2 washers to drop the head 5 mm which would allow the toe link and the LCA arm to be parallel on a flat floor. I had my car corner balanced which caused more issues as it sits higher on the drivers side. So, the car needed 200 lbs of wt in the driver's seat to do this calculation. Even with this done, the washers on one side were slightly different than the other by a small amount. Cantrell Motor Sports did this work on their lifter laser suspension frame rig. This allows the tech to put a level on the arms. They also attached some additional weight to the center of the rear to mimic compression. Not sure how they got the droop measurements, may be a jackstand underneath the tranny then lowered the lift about 1 inch. You need 1 inch both ways to get the center of the arc. Then they put in the washers to correct the level and measured the toe for each point, flat, droop and compression. They charged me a lot for this work I believe 2 hrs of shop time @ $160/hr. Did both front and rear. This was a couple of years ago.
Thanks for all the information. It does look like bump steer gauges are available for DIY'ers like myself, so maybe that's a possibility. If I knew of a good shop locally I'd head there but the ones I'm aware of are all in the bay area.

If possible, I'd love to see a picture of the geometry of your LCA and toe arm while your car is static on level ground. Just curious what the angles look like with your lowered car and those parts.
 
#72 · (Edited)
The muffler is in the way to get a good straight shot on both sides from the floor. I believe that the picture in post 67 was on a lift so full suspension droop. The toe links are angled down towards the transmission on my dropped car, so that is the reason Elephant uses a angled head to position the stud back to the center of its range of articulation.

Auto part Vehicle Suspension part Exhaust system Automotive exhaust
Auto part Tire Vehicle Hood Automotive wheel system
 
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#73 ·
The muffler is in the way to get a good straight shot on both sides from the floor. I believe that the picture in post 67 was on a lift so full suspension droop. The toe links are angled down towards the transmission on my dropped car, so that is the reason Elephant uses a angled head to position the stud back to the center of its range of articulation.
Makes sense! I did notice something odd in the photos you just posted, now I am not sure if I am seeing it wrong, or if one of our coilover setups are installed incorrectly. I am confused about why your coilover height lock rings are not seated on the top of the hub. Maybe it's just the photo? See mine and the instructions.

Photography Auto part


Auto part Suspension part Disc brake Vehicle brake Suspension


Text Font Diagram Parallel Line art
 
#74 · (Edited)
Hyrax, Thanks, I will snug it up, as I will be changing my wheels/tires today. The car is going into the shop next month for a suspension check up, more camber in f and a slight ride height reduction in the rear. Also, all four ride height coilover springs will be assessed to assure they are all about the sag after a couple of years. I had the cross weights done directly after the install so the corner balance is most likely off a little.

If you are going to get adjustable swaybars and drop links, I would highly suggest you get the collar type in front with the longer drop link. There is much less binding on that system than on mine. Tarett makes both, but when I had the suspension built, I never envisioned a 35mm drop, more like what you ended with. So, later I saw those extended drop links for the front and wondered why I did not order those. They are about $100/set more, but well worth it. Maybe it does not fit the Ohlin shock body?

Going back to a couple of threads you pulled forward for 2007-2008, seems there was a lot more talk about bumpsteer than today. Not exactly sure why that is, as the cause is still there. Mooty says its inherent in the way the Cayman suspension was designed. So, it makes sense to fix it as it appears at the worst times, like compressing the outside rear wheel/tire, which means going to the top of the suspension arc which changes the toe alignment to almost a toe out mid corner. The front can also be affected, but in a different way as the steering rack is now in my car 35mm too low. Some owners block up the steering rack with spacers, while I simply used Elephants tie rod with the head angle changed to move the stud to the center of articulation.


 
#75 ·
Hyrax, Thanks, I will snug it up, as I will be changing my wheels/tires today. The car is going into the shop next month for a suspension check up, more camber in f and a slight ride height reduction in the rear. Also, all four ride height coilover springs will be assessed to assure they are all about the sag after a couple of years. I had the cross weights done directly after the install so the corner balance is most likely off a little.

If you are going to get adjustable swaybars and drop links, I would highly suggest you get the collar type in front with the longer drop link. There is much less binding on that system than on mine. Tarett makes both, but when I had the suspension built, I never envisioned a 35mm drop, more like what you ended with. So, later I saw those extended drop links for the front and wondered why I did not order those. They are about $100/set more, but well worth it. Maybe it does not fit the Ohlin shock body?

Going back to a couple of threads you pulled forward for 2007-2008, seems there was a lot more talk about bumpsteer than today. Not exactly sure why that is, as the cause is still there. Mooty says its inherent in the way the Cayman suspension was designed. So, it makes sense to fix it as it appears at the worst times, like compressing the outside rear wheel/tire, which means going to the top of the suspension arc which changes the toe alignment to almost a toe out mid corner. The front can also be affected, but in a different way as the steering rack is now in my car 35mm too low. Some owners block up the steering rack with spacers, while I simply used Elephants tie rod with the head angle changed to move the stud to the center of articulation.
Since that picture you took was from your car on the ground, be careful about moving that lock ring down to sit on the hub. It looks like your car may have been adjusted to sit that way, so you may want the shop to fix it when they readjust your ride height. If you put it down now it looks like it'll lower your rear end substantially.

Thank you for that suggestion on the collar style links, I'll speak to Ira and see what he thinks. I do plan on getting his swaybars, having that adjustability sounds super nice.

It is definitely an inherent issue with MacPherson suspension setups, it's too bad Porsche saved some money and went this route rather than multi-link like on the 911. Got to do what they can to keep those cars a little faster than the Cayman/Boxter I guess, since this is the better platform! I will definitely get the front bumpsteer fixed at some point too, but the rear scares me a lot more. Losing the rear end is a lot more dangerous and I was not very confident in my car after I experienced that.
 
#76 ·
I actually have both rear Ohlin height adjuster on top of the uprights as the instructions recommend. It just the angle of the picture does not reveal the ring. Thank you for your heads up.
 
#77 ·
No worries! I can see the lock ring, the weird thing to me is that the sleeve that is supposed to go inside of the hub looks like it is sitting on top, then the lock ring on top of that. Compare yours to mine. Maybe it is just the photo.
 
#78 · (Edited)
Ok, what you are seeing is the rear height spacer (which is longer than the front spacer) and the lock ring. Yes it sticks out about 1 inch above the hub and sticks out the bottom about 3/4 of an inch. On my car if you pushed the sleeve all the way down to be flush on top of the hub, I would not be able to adjust the Golden knob and it would most likely hit the axle rubber boot dust cover. Just the install compensation reflective the ride height difference between cars. I need to use my thumb only to turn the golden knob, I do not have enough room between the Ohlin body and the boot to use my finger and my thumb. I'm glad we had this discussion, as I have no room left for lowering the rear of the car 5mm from 340 mm to 335 mm on my visit to Cantrell. I need that space to be able to adjust my compression/rebound. Maybe they know of a way to lower without affecting the knob to boot clearance.

See the attached photo from ArcFlash, who sells Ohlins. Joshua, what do you think about the golden knob to axle boot clearance?
 
#79 ·
Ok, what you are seeing is the rear height spacer (which is longer than the front spacer) and the lock ring. Yes it sticks out about 1 inch above the hub and sticks out the bottom about 3/4 of an inch. On my car if you pushed the sleeve all the way down to be flush on top of the hub, I would not be able to adjust the Golden knob and it would most likely hit the axle rubber boot dust cover. Just the install compensation reflective the ride height difference between cars. I need to use my thumb only to turn the golden knob, I do not have enough room between the Ohlin body and the boot to use my finger and my thumb. I'm glad we had this discussion, as I have no room left for lowering the rear of the car 5mm from 340 mm to 335 mm on my visit to Cantrell. I need that space to be able to adjust my compression/rebound. Maybe they know of a way to lower without affecting the knob to boot clearance.
Interesting, I'll have to check my clearance. You're definitely a little lower than me but I didn't nice any hardships with the sleeve being too long. Maybe I used the longer one on the front?

It looks like you added the elephant eccentric toe lockout plates to your car. Do you think those are required? I am surprised Porsche used a system that can slip, but I suppose they probably didn't design it for people using slicks on a track.
 
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