kuuner

Wish me luck guys...

Tomorrow morning, Prestige Porsche in Denver is installing 315/30/18's in the rear of my 2002 TT. It's lowered with PSS'9s on 11" stock turbo wheels.

Half the shop says they won't fit at all, the other half say they will fit because the shock tower on the PSS'9's are smaller than stock so they shouldn't rub but might rub on the fender but have the fender roller tool ready if needed.

I hope they fit! Putting Yokoham Advan Sports all around with 240/35's in the front.

Questions:

1)Why are there only three performance shops in the entire redneck state of Denver working on Porsches?

2)Will the tires mess with my AWD? Even the OEM tires are staggered and I hear that different size tires will adversely affect the AWD.

3) are the TT's detuned from factory so that the HP output is not what it is capable of? How much more HP could you realize with exhaust/ECU reflash? What else could you do without cracking the case and/or putting on larger turbos?

amerlemans

Wow, Denver is now a state?...just busting your ***** ......Would you really call it a redneck area though? I just don't think redneck when I think of Denver (only been once) I live about 45 minutes outside of Washington, DC and I know of only three performance shops worthy of working on PCars. I don't think there are a plethora of Pcar tuner shops in any one area..be it a large Metro area like DC or Denver or anywhere.......until you hit California.

ca993twin

Kuner,

I just looked up the specs on your tires choices on tirerack:
I couldn't find 240x35x18 listed for Advan Sport. However, this is what I did find:
315x30x18 25.4" diam, 817 revs per mile
245x35x18 24.7" diam, 840 revs per mile

Its very hard to find out the optimum difference for the viscous coupler. I've heard that it can tolerate differences as great as 5%. That number seems HUGE to me, but what do I know? If I were to guess, I would think you'd want the tires closer to the same size, with the rears spinning a tiny bit faster than the fronts.

A 245x40x18 is 25.6" diam and 810 revs per mile. This is a better match to the rears.

On your last question, your car is limited by the smaller turbos. The normal road to simple, bolt on HP is remapped ECU, larger (hybrid) turbos, and 100 cell race cats of large diameter. I don't know where you live, but there are many shops that extract MONSTER HP out of a 996TT (yes, I'm jealous).

<edit>... ahhh, I see... Denver.

Good luck.

wross996tt

I would never go there again.

They will definately fit. I had the same size rear MPSCs 315/30 and 235/40 in front. No rubbing

I just put 315/25-19 and 235/35-19 Yokos on...unfortunately the rain prevented me testing them...but they fit no problem.

Good question...I go to Orrin at Eurosport for Indy and Stevinson for dealer stuff.

I had 315 rear and 235 fronts? why 240?
Specification Sidewall Radius Diameter Circumference Revs/Mile Difference
315/30-18 3.7in 12.7in 25.4in 79.9in 793 0.0%
240/35-18 3.3in 12.3in 24.6in 77.3in 819 -3.2%

Does not look good. here is mine:

Specification Sidewall Radius Diameter Circumference Revs/Mile Difference
315/30-18 3.7in 12.7in 25.4in 79.9in 793 0.0%
235/40-18 3.7in 12.7in 25.4in 79.8in 794 -0.2%

They are tuned to meet many requirements...e.g., EPA, DOT, and a varied customer base.
depends on the flash and exhaust, but probably 50-80...well worth it.
Intake/filter, Intake plenum...what the heck...hybrid turbos...just DO IT.

I'll be down there tomorrow...if you want to see.

Duane993

The rule of thumb is the tire diameter should be within 4% of stock and within 4% front to rear. I've heard mixed luck with rolling the rear fender lips. Some paint cracking on the edges if you don't mind brush touch up on an area you can't see. Although I've heard few unpleasent experiences with the cracked paint going to the outside of the fender flare. The rear fender lips of the 996 iare quite a bit thicker than the 993 and earlier cars. Lack of performance shops for Porsche seems to be a problem except in California and Florida. But if the dealer is willing to do the work at a reasonable price..why not let them do it.

Duane993

Good luck and let us know who it goes

kuuner

Wross...beautiful car! I am supposed to drop the TT off at Eursoport to check the PSS9's. They make a noise at slow speed when turning. He (Bob Cramer) says it sounds normal in that it's a race suspension and not supposed to be quiet but he agreed to look at it.

CATwin...I could be mistaken about the fronts. I'll find out tomorrow. I hope they are the 35 series.


Amerlemans...Still trying to get used to Denver. From Pasadena, Cali but work moved me out here a couple of years ago. Not a bad place but the friggin rock chips drive us Californians completely crazy!

Thanks guys for the input and feedback. I think this is an incredible site with some awesome P-Cars. My second one. Well...kind of. Bought a C4 cab three weeks ago and traded it in two weeks ago because it wasn't as fast as I wanted it to be...so I guess you could say it's still my first real P-Car. Big difference from the A8L I've been used to driving.

I'll post update tomorrow to let you know how it all went.


P.S...not looking forward to a possible fender roll Duane!

srf506

4% is what I've always been told too. According to my buddies at two Porsche dealerships (Hilton Head and Orlando) anything else really screws up the AWD system, making the handling inconsistent and uncertain and causing major component distress. Officially, Porsche recommends you don't even mess with different wheels and tires. Good luck and let us know how it goes.

Mikelly

Just bought a set of 315/30/18 & 235/40/18 Michelin Pilot Sport Cups, mounted on Stock Turbo wheels. Hopefully I'll know if mine rub or not by tomorrow!

Mike

srf506

Man, must look like a F-1 car with that size rubber on it! Post pics please.

wross996tt

They can fix it. You will need the stock rubber washer. Orrin knows. Tell him I sent you/said hi!

kuuner

Well...

Got the tires on. WOW! That is a lot of meat (Why can't my wife say that to me!?).

Unbelievable how they squeeze in there in the back. You'd think it was a Ford 9" with slicks on it.

Had to push up an L bracket holding the cooling line that was pushing the fender liner into the tire an 1/8" on the right side but once we bent it back, tire has about 3/8" clearance all around front and back. Looks beautiful. Still can't believe they fit.

Off to see Orrin tomorrow! I'll say hi to him for ya.

Oh...and as soon as I figure out how to post pics...I'll post.

Do I have to buy the "Upgraded" membership? When I try to load a pic it gives me like 140K of max size, but the pics are like 700K! Any advice on that?

ca993twin

you can use Microsoft "Paint" (standard on all PCs). Open the picture then go to the "Image" pull-down menu, and go to "stretch & skew". Put in some number like 40% for both horizontal and vertical, then "save as" (I use the name "smallimgxxxx.jpg"). Now you have a smaller image to upload to web boards.

What size tires did you end up with on the front? How is the handling?

wross996tt

Kuner...what I do is post them (upload them) to Photobucket and then click on the url link and copy that to the post here.

PHOTOBUCKET

Techno Duck

If you are having trouble posting the images, you can email them to me at jjeng951 at gmail.com

I have plenty of hosting space.

I love the look of wide tires. I almost bought a '85 grey market 930 with 15-inch Gotti wheels. Not sure of the width on them, but the tires were 305's in the rear. Ill never forget the look (or the sound) of the car as the owner backed it out of the driveway.