Yes 265-275 for track only or maybe with R compound should be nice, I will use my car 90% maybe for track days, time attack, etc so not a big trouble to have separate 18inch wheels dedicated with slicks and running 245/305 MPSC2 on 19, but I would try a 265/305 MPSC2 for example, fronts would be only 0.4% bigger so guess could be used even for AWD setups if wanted

Seeing for example the new M4 GTS running 265 front MPSC2 or any of the newer cars runs at least 9.5-10J rims with wide tires, 24/25/27-64/57-18 being a normal sized slick, if not having almost the same grip I find to be more and more difficult to keep up/being faster than these new setups

Also trying to resist to keep in place A/C (summers are hot here), all interior parts, etc..
I have some connections with somebody who builts custom fenders and other 911 fiber/carbon parts for well known companies and can try to get a direct quote from him, but we will have to be patient with delivery, I would be interested too into some parts at the end of this season

 

our a/c system actually has a fuel cooler built into it unless you have bypassed that function with afttermarket system.

 

Right, I remember now reading about it, thanks for the warning.

On another note, was looking at this new cayman pro4 - "cup" version, strong setup but quite expensive at 165K Euros

http://www.autobild.de/artikel/porsc...h-8638459.html

please use translate function from your browser as the article is written in German

 

I don't have A/C in my car. You loose 20+ lbs by removing it. BTW, the fuel cooler on only works when the A/C in ON. Many of the Euro spec 996TT cars did not have the fuel cooler installed. None of the GT3s have a fuel cooler...

 

Intake charge temp in a NA GT3 vs. turbo - so not really apples to apples.

I am very curious how much of an effect the cooler actually has. I am planning on trying to do a bit of data logging later this year, so maybe I can get several back-to-back autobahn runs this summer with the cooler on and off and see what effect it has (i.e. when timing is pulled, etc.). Wonder where it would be easy to take a fuel temp. reading...

 

I've never used the fuel cooler and run the car hard for 30min track sessions in +120F ambient track temps. Logs look good with hardly any ignition retard, just a few -1s and -2s. No issues.. Again, many of the Euro 996TTs came from the factory without a cooler...

 

I know what you are saying, but if it had absolutely no effect, Porsche wouldn't have installed it, I hope...

Academic curiosity :-)
My euro 996 has one, so I can play. I will likely need to swap it out anyway, as I need to run a 997tt air filter to get my GT2 decklid to close w/o resting on the airbox. Besides, I want to take advantage of the CAI and ram air.

 

Guys I have found for sale 2 sets of center lock wheels, but afraid a bit on the ETs

they are
10J et25 x4pcs
11J ET0 x2pcs and 11J ET15 x2pcs

Guess in case I need 12-12.5J can just buy the BBS stuff to make them bigger, what do you say?

Also I will have to buy a center lock conversion

 

Running a 10" front will require a lot of modding if you are going to be running an aggressive track oriented ride height where the top of the will be flush with the fender or tuck under slightly. At more moderate ride heights it's a little easier. I run 100/120 ride height which is about 1/2 -3/4" below GT2 ride height. For 10" fronts you will need to rotate our upper mounts for additional camber. This is a must so obviously you need upper camber plates that can be flipped. You will need about -3.5º camber. You will need to get max camber at the strut tops while running minimum to zero shims on the lower control arms. If you have adjusters up top, you will need to grind out the shock tower opening to make room for the adjusters. Although some people are weary about grinding out a portion of the chassis, it's not a big deal. Cup cars have this done at the factory. You will also need small diameter springs in the front, generally 2.25" springs so that you can get the inside wheel right up against the springs or spring seats. 2mm room is all you need. This translates to a 10" wheel ET38-39. You will also need to roll the front fenders very tightly beyond OEM. The other problem with running a relatively shallow ET38 offset is that this makes the steering angle greater. You will need to relocate the front radiators slightly forward and trim the radiator brackets to create more room for the front tire as it turns towards the fender liner. This will give you 1/2-3/4" more room in the front. You will also want to install GT2 fender liners as they are thinner than the stock TT units. You will need to heat and mold the liners to create as much room in the front as possible. The more aggressive your wheel offset, the greater the steering arc the wheel makes and as such clearance becomes even more critical if you want to be able to keep your caster within specification. Once all this is done, you will want to pull the wheel forward as close to the fender liner as possible without touching the fender liner to get max caster. Every mm counts if you want to be able to run a low ride height where the front tire can tuck up under the fender.

I am currently swapping to 275/335 and have gone through all the gymnastics and modifications listed above to make this work. A 9.5" front options makes this a lot more flexible as you can run a 9.5 ET45 wheel which gives you more clearance. With a 9.5, you will be able to pull the whole wheel assembly further forward giving you back some badly needed caster. A 9.5s allow you to run up to a 275 although 265 would be ideal. You can even fit a 245 although it will be rather stretched which is ok.

Long story short, no way a 10" ET25 will work... For the rear, running -2.5º camber, a 12.5" ET45-47 is good when running a 335, an ET 40-42 when running a 305-315.

 

Got that master

Second option comes now first, 997.2 cup (2012 EU model/ 2013? US), owner doesnt know ET and Js but used to run
25/64-18 and 305/68-18 Michelins, I can get a good deal for these including used slicks

also center lock version. My idea was the same.. 275/335 as the 305 slicks are somewhere 33-338mm wide and 255 slicks are optimal even on a 10J tire but can be used for 9.5J too

Wasnt able to use gt3 drop links rear on the KW v3 only the regular ones
and wasnt able to use even the regular ones in front, had to put stock

using 3.5 camber F and 2.4 R, car feels way better, put in also some stiffer (stiffest on V3) springs in front and now car is way more balanced, converted also to RWD, relearn mode is ON

 

Forgot to add that already bent the radiators brackets and specs for Cups seem to be these:

997.2 Cup
front wheel 9.5 X18 offset 37
rear wheels 12X18 offset 30

 

The front wheel would work but the offset is still too aggressive. 44 is ideal. Rear won't work. What I.D springs are you using?

Have you converted to center lock? If you're planning to make sure you use the Cup parts. The street center lock is no good.

The 305/680-18s will be a tall order (no pun intended) to fit on the TT. The 680s are just very tall at 26.8" and have a very square sidewall. You won't be able to run those unless you are at a relatively high ride height or with extremely stiff springs. The TT wheel well is extremely shallow compared to a Cup because of the intercooler duct that runs above it in our case.

 

I have just gave up the idea of center locks, seems way too complicated and expensive and no benefits really

As I can not find some of the US brands over here liek hre, ccw, finspeed etc and the BBS are like 7000+$ for all 4 corners I have tried some of the OZ variants

new OZ challenge (track rims as OZ indicates) are just 8/8.5/11J... to narrow
old OZ alleggerita happens to be available in 8/8.5/9/10/11/12 but

there is no 9.5 for front so have to go for 9 or 10J
9X18 ET 43
10X18 ET 40

for the rears the only logic choice might be
12X18 ET 45


On the other hand I have found some custom wheels fabricators that are willing to build forged competition wheels that clear the 380mm brakes and they can go up to 13J !!!!!
they have also anti-slip knurling option, price is almost 5000$ for the set

So, should we go for 13J in the back ? I have rolled fenders and gt2 liners, can do also some work ion the IC ducting etc...

Pwdrhound are you going to try 335s on 12J or moving to wider rims?

In the meantime I would give a chance just to see how they work on my 19" wheels, thinking to buy

25/64-19 and install on a 8.5J F (ideal size by michelin 10J !!!)
29/67-19 and install in a 12J R (ideal size by michelin 11.5J)

theese are the tires used on 430 challenge and the fronts on 458 challenge as well, they moved to 305/67 rears on the 458s

And a final question, is there any way we can run a 650 or even 660 slick in front ?

 

Fadi, ask from http://www.ntmwheels.com/en-US/home-page
My totally custom 3-piece set was €2000,-. Wheels are made in Italy, very durable and light.





8,5x18 et40 & 11x18 et55, weighs F:8,9 ja R:9,3 kg/each

 

Good tip, thanks! Your car and rims look great too, will give them a call, do they clear 380mm brakes ?

What kind of wing is that? soon I will be over one of those