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Cayman The Destroyer!
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So Ken are you going to take one for the turbo team? I for one will not be doing any hole shots at the strip or on the street. I'm not worried about my clutch, but the tranny and 1/2 shafts aren't exactly stressed for all that torque.

Power to weight wise these are definitely 10 second cars. Better tranny mounts, shocks that would allow the front end to rise and sticky tires will fix the 60ft time but who's gonna bother with that?:burnout:
 

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Discussion Starter · #62 ·
Oh, I don't intend to do real hole shots. I can't set the clutch up to do it and I wouldn't if I could. I will do accels using an "aggressive launch".

Granted that first gear is the maximum load on the half shaft, but the load is limited by tire adhesion. If I assume a 15 inch vertical cg and a tire coefficient of friction of 1.0, I get a 29/71 weight distribution at 1g accel (I know this doesn't make sense, since a 1g accel would require a 0/100 weight distribution, but it represents something of a worst case). That results in a vertical load and a max wheel thrust at breakaway of approx 2240 lb. With a tire diameter of 1.06 ft, then the maximum rear wheel torque at breakaway is 2375 ft-lb. Using a total of 33% loss in a first gear accel (based on stock data of 0.66g peak accel and an installed torque of 240 ft-lb), the maximum crank torque that can be applied at wheel breakaway is 276 ft-lb. That is only about 15% over stock, so I do not believe that half axle strength is an issue. If I could use the entire 415 ft-lb of torque in first gear, the car would do a wheelie and I would need tires with a coefficient of friction of more than 2.9 - definitely drag tires.

In my car, I reach breakaway torque at any RPM above 3200 in low boost. That is consistent with my only full throttle first gear accel when the rear wheels broke away at about 3500 RPM. This means that I can do an aggressive launch without a lot of clutch slippage.

Interestingly, in a full throttle second gear accel, the rear wheel torque is about 2100 ft-lb, not very far from breakaway torque. I'll bet your car will come very close to breakaway in a full throttle second gear accel.
 

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Discussion Starter · #63 ·
And you are right, shocks that allow the front to rise transfer more weight to the drive tires and allow higher drive wheel torque. That works for tires that have a coefficient of friction less than that required to produce a 0/100 weight distribution. I could get close to that in my Olds and learned a valuable lesson when I installed a full-locking diff. Coming out of the hole, I lost a little bit of traction on one side after hooking up really well. The car started rotating and the steering wheel did precisely nothing. A couple of throttle flutters got it straightened out, but for a few milliseconds I was wondering what that wall would feel like. I decided full-lock diffs were not for me.
 

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Cayman The Destroyer!
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Ken, nice analysis. Your are correct about tire spin in 2nd gear. With a air temp of 110, in low boost I get wheel spin as I cross 4,000rpm. It will be very interesting with say 70 degree ambient air!
 

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Discussion Starter · #65 ·
Ken, nice analysis. Your are correct about tire spin in 2nd gear. With a air temp of 110, in low boost I get wheel spin as I cross 4,000rpm. It will be very interesting with say 70 degree ambient air!
That is really entertaining. Drifting in a straight line. It is a whole new ball game. I can't wait to start learning how to exploit my car's new capabilities.
 

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entertaining talk guys :)

ken did you also upgrade your meth noozle?

maybe thats only for gen2 cars - mike told me about his result son his spyder

when changing the noozle that sprays finer and uppiong the meth controller

setting - i just got the noozle yesterday - will try to get it in this weekend to

check. mike was all enthusiastic about his spyder it being even a good match

for his stock 2013 GT-R, lol :dance:
 

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I am a bit amazed that you placed your noozle so far away from the throttle body - I thought of doing the same as its the only piece of metal where you can get the noozle in really - but eventually i chose to get it right into the very silicone hose precisely before the throttle body

can't wait to compare the difference in noozle and meth setting - it comes on now much earlier - so you should see the led also turn green at times and not just remain red i guess?

the great thing about the meth addition i found out to be in my car is that it is not losing power on the higher rpms but pulls much more nicely through all the way up
not quite like yours kenny - but well enough and my PDK makes me not have to wonder about shifiting or limiters at all, lol :cheers:
 

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Discussion Starter · #69 · (Edited)
Alex, your observations are exactly like mine. The methanol allows more aggressive tuning at the higher boosts and revs. And yes, the red light comes on sooner and it goes to green because the pump is operating in the duty cycle/pressure design range. It is pretty simple, the first guess at nozzle size wasn't quite right. Mike worked it and improved it and I can't ask for better.

Your driving impressions are also very similar to mine: The car does not want to quit pulling. I'll bet it makes for some interesting shifts in your PDK.

As to the location of the nozzle, far enough away to allow complete vaporization and mixing prior to ducting to individual cylinders to ensure consistent meth/air mixture. That is a bit of the obvious, but I have no data whatsoever to judge on the adequacy of either your or my location. If it works, it works.
 

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Discussion Starter · #70 ·
Here is the dyno chart from the next to last configuration. The two files are low boost (6 psi) and high boost (10 psi). I will do track work on low boost. As noted earlier, we tuned low boost for constant torque. From a visual analysis, the average torque from 3500 to 7000 rpm is about 358 ft-lb with a max of 372 ft-lb and a min (in the range) of about 340 ft-lb. That is amazingly flat and equates to essentially constant throttle torque response across the entire operating band. As noted earlier, the response of the car is a very linear pull all the way up the RPM scale.

In high boost, the car pulls harder and harder as the RPM increases through about 5500 RPM then is essentially level to past 7000 RPM. That response is primarily due to the methanol benefit increasing as RPM increases because the timing can get more aggressive at higher boost levels. The torque curve is not quite as flat as low boost, but the variation over the 3500 - 7000 RPM range is still only about 10%.



We talked about making some 12 psi runs, but decided to leave well enough alone. At 10 psi, the tires were already slipping on the dyno and to do 12 psi, we would have to put a bunch of weight in the back of the car. Also, the attainment of full boost would be a little later on the RPM scale, probably somewhere in the neighborhood 3200 RPM, so the drivability of the car on the street could be compromised. But we have definitely not seen all the power that the car is capable of making. I just didn't want to tempt fate by going to 12 psi and burning up a set of rear tires just to see what 12 would do. Linear energy estimation predicts WHP at 12 psi to be in the 580 range, but the methanol has a higher return at higher boost, so it is possible that she could do a little better than that.

After these runs were done, we went to a smaller methanol nozzle and a higher pump duty cycle (and resulting higher nozzle pressure) to get the same methanol flow rate but with better atomization and better control in dynamic throttle environments. In runs on the street with the new nozzle setup, I think the car is even stronger than indicated on the dyno, but it may be just wishful thinking. As soon as I get my data back into the car, I will do some accels and post the results. I'll get her on the track Sept 20 and post impressions.

We started this project to build a car that could have exceptional performance but good street manners, and we have succeeded. The Sachs racing clutch is very street friendly and the 3.7 liter engine is happier than the 3.4 at low RPM. The exhaust tone is slightly lower and definitely richer than the 3.4, sounding more like a big block. The idle growl is also richer and more tonally pleasing, if you like that grumbly tone that is somewhere between don't-mess-with-me and outright menacing.

This old boy is a very happy camper.
 

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This is my first post, but I've been lurking on Planet 9 for a while, and I want you to know that these posts are killing me. I used to own a 2005 Boxster S when I lived in a little town called Topanga, which was just south of Malibu with its amazing canyon roads, onto which I deposited a few sets of PS2 tires. I unfortunately moved to Florida and got so depressed driving my car in stop and go traffic that I sold it. I of course then really missed the Boxster and recently bought a 2007 Boxster S with only 8,000 miles on the odometer. After reading all of the posts about the TPC turbo kit, I just had the stage 2 version installed (along with some sway bars), and the difference is amazing.

I'm really happy with the upgrade, except that I keep reading your damn posts about the 2.7 liter engines with methanol injection...and now you go and post the very impressive dyno sheet and I'm wondering how I can save up another $27k and convince my wife that that's how I should spend our retirement money. Thanks for that! :eek:
 

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Discussion Starter · #72 ·
Well, Bonzai, I would still have the TPC turbo 3.4 if the dang thing hadn't suffered a D-chunk cylinder failure. Faced with cost of replacing the 3.4, going to the 3.7 was just marginally more expensive. After making that decision, other ideas kept creeping in, with the justification that the car was highly disassembled anyway, so why not?? The only unplanned event was the clutch failure.

I'm glad you like the turbo kit and sways. Do you track the car?
 

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I've never tracked a car, but I've been considering it. I even started to look at the PCA DE calendar and the Chin Motorsports schedule for Homestead and Palm Beach International Raceway, but I haven't tried it yet. I have these horrible images of pointing Civics past me as I flail my attempts at heel toe downshifts. Any advice for a novice who doesn't want to embarrass himself?
 

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Cayman The Destroyer!
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Check your ego at the door. Prepare to learn and have fun! You'll be in an instructed group with other beginners so no big deal.
 

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Discussion Starter · #75 ·
I've never tracked a car, but I've been considering it. I even started to look at the PCA DE calendar and the Chin Motorsports schedule for Homestead and Palm Beach International Raceway, but I haven't tried it yet. I have these horrible images of pointing Civics past me as I flail my attempts at heel toe downshifts. Any advice for a novice who doesn't want to embarrass himself?
Yes. Just go do it. And don't feel bad about being a beginner. My first time out, I was lapped twice in one 20 min session by a '76 Pontiac. As far as track driving goes, you are in the basic math class, so don't worry that you don't know algebra or calculus. If you go on a DE, an instructor will go with you and teach you the basics of line, turn-in, apex, and track out while being smooth. He will also keep you safe. You should have no expectations beyond learning how to drive your car beyond what you do on the street. You will find that the car is far more capable than you. Forget things like heel-toe, trail braking, and any other skill other than learning how to brake the car and turn the car. With the turbo, you have much more power than you need for a beginner. Turn the controller off so that you are operating at minimum boost. I don't know if you have a LSD or not, but it is better if you don't, since overpowering a turn exit will simply spin the inside wheel.

Nobody expects you to be a capable Porsche driver your first time out, so don't expect it from yourself. Your car is highly capable. It will take many track sessions for you to learn how to truly utilize it. Enjoy it with the understanding that you are driving one of the best cars out there.
 

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I don't have a boost controller or an LSD. In my case the boost controller would be a "lack of self controller" with some expensive repairs because 15 psi isn't recommended on a high compression stock engine!

Your unfortunate experience with your engine failure gave me an idea...I just have to figure out how to D chunk a cylinder as well and then the 3.7 liter with methanol injection upgrade would make sense.
 

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Discussion Starter · #77 ·
In that case, you are good to go. if you want to talk about aspects of tracking your car, feel free to PM me, because I can give you a better aspect of the low skill driver than the high skill driver.
 

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Great posts ken,

Your car is just simply amazing!

Which meth noozle #size did you

Go for in the end? #5 or #6?

I am waiting to hear from mike soon,

I guess this must have been a busy week for him

Soon enough he'll strap his spyder back on the dyno

To finish the setup :)

Enjoy your baby - she is stunning!
 

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Discussion Starter · #79 · (Edited)
I have a #5 running at 70% duty cycle ramp . We set that on the street doing accels in low boost. The dyno was run on the #10 nozzle at 35 % duty cycle ramp which produced really impressive power, but the pump could never achieve good operating pressure, so there was real concern that the methanol was "pulsing" instead of "spraying". I wasn't too worried about it because my nozzle is about 10 inches ahead of the throttle body, so I felt reasonably confident that we were getting very good vaporization before the vapor gets to the cylinder. But, as I said, after we went to the #5 with the higher duty cycle, the pump pressure was stable going through about 3500 RPM at WOT. The pump can put out 250 psi, so the spray pattern just has to be conical and stable. As I said, I think the car pulls more than with the #10. I could have left the car at TPC until they got back from the race to have updated dyno results, but I really needed to get down the road.

What impressed me was that when Mike Levitas saw that the #5 was better, he provided the nozzle and installation at no cost. I did help the mechanic install the nozzle, but bringing my car to the shop was the only effort required of me.
 
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In my case going from #10 and 3-4
To #5 and 6-7 i feel the latter is better

in any case i'll wait for Mike's updated mapping
for the gen2 car That will either be a #5 and 8
Or a #6 and ...? yet to be figured out :)

With #5 and 8 and his almost completed new mapping
he already reached a 450whp on a gen2 spyder with 5psi on his dyno
and i am longing to run that, too lol

another "problem" i now have is when i launch from standstill heavily with psm on it kills my power too much - but when i turn psm off my car's back end often quickly goes sideways...maybe i need wider wheels ... Running 275 tires on 11" OZ wheel
 
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