I did an alignment on the car yesterday. For those interested in an aggressive alignment, here are the specs... Keep in mind values are in degrees and minutes. To convert minutes to degrees, divide minutes by 60 (i.e. 30' = 0.50º).

Ride height:
LF: 102mm RF: 102
LR: 123mm RR: 123

Wheels:
18x10
18x13

Tires:
275/35/18
335/30/18

Springs:
Front: 1400 main / 150 tender
Rear: 1500 main / 250 tender

Car weight:
3214 lbs with 3/4 fuel (minus driver)
Weight distribution F/R = 38/62%
Cross weight = 12 lbs

FRONT AXLE (castor is 8.0º)
[url=https://flic.kr/p/J6a7HD]


REAR AXLE
[url=https://flic.kr/p/K2y3ii]


Total car weight includes 190 lbs of driver ballast, 94 lbs of alignment equipment, and 3/4 tank of fuel.
[url=https://flic.kr/p/JAKACw]


[url=https://flic.kr/p/K2y2Zx]

 

Perfect timing - just finished a track weekend and was told I could get better with some more aggressive alignment specs and a bit lower on my coils.

 

I just did mine 2 weeks ago. Think I should have went a bit more aggressive but I'm on the street more. Only running 1.5 camber up front a 1.8 in the rear.

 

You can crank in a lot more front camber without worry. The front is light and not hard on tires under street use. For street I would go -2.0 to -2.5 in the front.

 

must be nice to have all that contact patch up front! damn.. and obviously with a 10" wheel -3.2 will be required i'm assuming? makes me want to go RWD sooner!

i just installed the cup arms and have it pretty mild @ -2.3F.. but 9 degrees caster... night and day. quite happy with how it responds!

 

I wish I would have gone 275 like John did. I'm running 255/35/19 and am 100% positive they are harder to fit than 275/30/19 (or 275/35/18). Going to end up switching next year I think.
If you do the radiator mod, a 275 on a 9.5 I don't think is to hard to fit with the proper offset. A 1.5-2 camber would be all thats needed.

 

With the 10" things get a little tricky especially at low ride heights as I'm at 102/123 which is 5/8" lower than GT2 spec. You really need a fully adjustable suspension to make that work and yes, you will need closer to -3 camber. At a higher ride height a 10" is not too bad but you will need to be able to flip your upper mounts for sure. A 9.5" front makes fitment a breeze as you can run a higher offset wheel You can make a 9.5" work easily without any sweat.

 

As you know, fitting a 9.5 is a no brainer if you do the radiator mod which is very straight forward. For any one interested, I have a brand new set of 18x9.5x12.5 F110s available for sale but haven't advertised them yet. Forged, ultra lightweight, bead knurling, the works.. They are pictured below with 275/335s. They only have about 100 miles of on them as they were used for fitment verification prior to moving to 10/13s. Mint condition... 9.5/12.5s actually give you the best flexibility as you can run 245-275 fronts and 305-335 rears.

[url=https://flic.kr/p/H7mYMM]

[url=https://flic.kr/p/HTpgJC]

[url=https://flic.kr/p/J9W1Cw]

 

pwdrhound,

What would those toes specs correlate to? I have read 1/16 toe in rear is ideal. Any thoughts or input? Would love some more knowledge on this topic as pertains to our cars.

Also, which bumper setup are you running?

 

Porsche measures toe in degrees and minutes (1º=60'). Measuring in degrees is the correct (more accurate) way of doing it as it is an angular measurement which is totally independent on wheel and tire diameter. Measuring in inches (or millimeters) is not the best way of doing is as it is not an angular value and is thus dependent of wheel diameter. With that said, assuming you have an 18" wheel with 1/16" toe, this is equivalent to 0.20º toe per side. To get your total toe you would double that figure and arrive at 1/8" (0.40º) total toe. This is within spec for a 996TT (0.17-0.50º) or 6GT2 (0.37-0.50º) but on the low side for a 996 Cup car which specifies total rear toe at 0.30-0.34' (0.50-0.57º).

I have always run 0.50º total rear toe. I would not go less on our cars due to the tail heavy nature which makes rear toe in paramount to maintain stability under braking and cornering.

 

Thanks for sharing! I always thought it funny that people suggested alignment in inches as well seeing no alignment shop uses those numbers. Yet people with track time and fairly reputable still reference it inches. Makes since when you are doing a ruler and tape garage floor alignment with you lifted jeep. Otherwise silly.

 

Is there any reason why you dont run full slicks? I assume car will be even faster on slicks, more than 1s/mile perhaps? I have seen Hoosiers A7 or R7 if I remember right ran by some here and also the classic slicks - Michelin, Pirelli, etc

 

I can get 15 sessions or almost 4 days out of a set of 275/335 NT01s at $1100 per set. Pirelli Slicks are in a 275/645 and 325/660 are $2400 per set and last about 8 sessions, or two days. That works out to $300 in tire wear per 30 minute session. Not exactly cheap. I'm brutal on tires though. I go through 7-8 sets of NT01s each year. If I was running slicks it would be double that which would amount to $36,000 in tire wear each year, or roughly $28K more than I spend on NT01s. Yeah, I'm willing to give up 2 seconds per lap from a cost perspective. Sure, to hammer out a time trial time I'd throw the slicks on. The other issue is that I'm already breaking hubs and other suspension components even on NT01s. With slicks providing much higher grip, it would only accelerate the maintenance schedule. I'm not a fan of Hoosiers, they don't come in the right sizing and they go away quick plus they're not much cheaper than the Pirellis...

 

Makes sense using R tires in this case, so the difference you see for a 1:40-1:50 minutes track would be like 2 seconds between 275/335 Rcompound and full slick and maybe another second or so compared to thinner 245/305? Just to have a slight idea where to put the money in

 

Correct. On a 2 min lap the 275/335 NT01 is 1.2 - 1.5 sec faster than the 245/305 NT01. The pirellis 275/325 would be 2+ sec faster than the 275/335 NT01s.