[PorschePh1le]

I posted this on Rennlist but the 981 section there seems to be pretty low traffic at least as far as track oriented people go. Any thoughts?

There are a few threads already on this, but it's weird how much the cars can vary so I figured I'd throw some more data out there. Obviously lower cars get more camber, automatically, so my 981S with normal susp. is not very cambered right now.

Stock alignment was -0.4 camber front, -1.6/-1.2 camber rear; 0 toe front, 1/16 and 3/32 toe in rear.

By sliding the camber adjustment bolts in the strut towers all the way inboard, I got camber in front to -1.3 and -1.1 (unsure why it is so low and why it is .2 off; they are definitely all the way in on both sides, as I removed the nuts to check). I have seen people talk about -1.5 camber stock and -1.7 or -1.8 with PASM or X73, but that didn't work for me.

Importantly for other DIY-oriented people, just moving my camber from ~0.4 to ~1.3 changed toe in front from zero to a full quarter inch out, which was super sketchy and frankly probably too much to even drive the 10 minutes to my local alignment folks. So don't do this without taking toe back in accordingly.

One other weird occurrence: my shop could get -1.8 camber on the right rear, but when it was that high the toe could not get more inward than zero. Only by backing down to -1.6 could they get it to where we needed, toe-wise. I don't know if something was bound or what the deal was, but I've seen zero other discussion on that particular problem. No big deal, since I didn't want more than .4 difference F/R anyway in camber to make it neutral/oversteer.

Final results (stock suspension 981 CS):

LF: -1.1 camber, 0 toe
RF: -1.3 camber, 0 toe
LR: -1.6 camber, 1/16 toe in
RR: -1.6 camber, 1/16 toe in

Will see how it fares at VIR July 15 and Barber August 5, but expect it will need camber plates or LCA's.

BTW: any coilovers have integrated camber plates, like the KW's did I ran on my M3?

 

[BillL223]

0 front toe is a good compromise for a street/track car. A slight amount of toe out (1/32") can help with turn in. Rear toe looks O.K. , my GT4 needed more for stability under hard braking but the rear geometry is a little different. I don't know of any coilovers that include camber plates. You should be able to add about 1 degree per side using them. I like GT3 style LCAs like the GT4 came with.

 

[mgent]

I've got Bilsteins, no camber plates included.... I went with the GT3 style LCAs in the front, and currently have -2.6 front and -2.3 rear camber... I'm still wearing the outer edges, and may go a bit more, but still drive it on the street so need to maintain some balance as well...

 

[NetMage]

After driving an NSX for ten years I'm used to a lot more toe out and feel like the stock alignment lacks the immediacy I'm used to in steering. The tow out is supposed to keep the steering mechanism under tension so it respond so more immediately. I have mine set around 0 now but think I would prefer a bit out. I'm probably going to see if the dealer will adjust it when they are doing an oil change.

BTW, the NSX and the Cayman were/are daily drivers.

 

[PorschePh1le]

The outsides of the fronts did wear excessively, as expected. Front left is medium-bad, and front right is pretty decent (VIR). It needs at least another degree. One more mod down the rabbit hole

 

[Gtdreirs]

Hi there, had the same experience with stock suspension where the outsides of the fronts copped it pretty bad. I also had an E92 M3 with KW's so decided to sort out the excessive body roll of the CS with KW clubsports. Yet to get it aligned but have been told without LCA's forget getting much camber.

 

[westwest888]

For another data point, this is what I did on a 2.7L Boxster with JRZ Touring suspension and Tarett Competition LCA on all 4 corners:

Sent from my iPad using Tapatalk

 

[PorschePh1le]

For another data point, this is what I did on a 2.7L Boxster with JRZ Touring suspension and Tarett Competition LCA on all 4 corners:

Sent from my iPad using Tapatalk

Was it stable under braking with ~0 rear toe?

 

[westwest888]

Was it stable under braking with ~0 rear toe?

Rock solid. I do have the tarett toe control link in the rear, so the alignment should hold as it was set statically. Maybe it gets wiggly with the rubber suspension.

Sent from my iPhone using Tapatalk

 

[PorschePh1le]

X-post from Rennlist, for posterity and in case it benefits anyone else. This is the next step of my ongoing suspension/alignment progression:

I got some used OEM 996 GT3 LCA's with RSS solid thrust bushings and unknown brand monoball inner ends. The install was much harder than expected, in part because the first few threads of the ball joints were marred from being pressed out with too much force (you're supposed to rely more on sledge-hammering the outside and less on pressing the crap out of the fragile threads, I believe). For me, including going to the shop to get a few things here and there, it was about a 6 hour job (including doing brake pads F/R, I did both at the same time).

The thrust bushings with the hole in middle worked for me. It did increase caster significantly, but that should be fine (good, even) as long as it doesn't rub. No rubbing so far.

You HAVE to turn the tie rod ends to get closer to zero toe to even drive to the shop. I used about 14mm of shims per side, and toe was ridiculous pre-adjustment (visibly pointed way in, much too high to drive on). I ended up turning each side around 7 turns to get it good enough to at least make it to the alignment shop.

The tie rod and ball joint nuts are one time use and easy to strip; don't cheap out on those. They're $5 each from many sources.

Final settings for me ended up at -2.4 camber, 0 toe, ~9.5 caster. Rear I left alone, which was already at -1.7 camber, 1/16 toe in per side. First track test is this weekend.

Oh, tools needed: 1/4 inch socket (13mm, torx to hold the ball joint that I can't recall the size); 1/2 inch socket (16mm, 18mm, 19mm, 21mm); torque wrench; breaker bar; ball joint scissor tool; blue threadlocker; 4 new nuts; box end wrenches (16mm, 18mm); sledgehammer or BFH if you dare; flashlight for far-back bolts; patience.

 

[PorschePh1le]

One more update for now.

I just returned from Barber Motorsports Park, and this alignment works really well (see last post above, -2.4 camber with 9.2-9.5 caster and 0 toe). Tire edge wear decreased a lot, and front end grip increased a lot. The car was pretty balanced, with a hint of oversteer if you got greedy with the throttle. 9.5 caster is about the max the car can handle with everything else stock, as shown by it very lightly touching the fender liner a couple of times (does not do it anymore, after wearing a mm or two of liner away). Tire wear on the street is TBD, but driving 700-800 miles round trip to Barber resulted in no noticeable inside edge wear. They could still use more camber, and will cord the outside before the inside.

I plan on leaving it alone until next track season, and probably going up to -3.0 degrees camber and leaving the rest as-is at some point. One of my buddies with -3.0 on his dual use car said outside still cords first if it's your spare car that only sees a few thousand street miles a year. :cheers: