What are 996 GT3 offsets? sorry, no hijack intended

 

YSS

I also live in OZ (Melbourne) and took delivery of my white GT3 in late May.

What a car !!! The sport button is very addictive....but also a cop magnet !!


I've ordered a set of 19 inch rims to fit the original cup sport tyres for track days (3-4 /year)and have replaced them with pilot sports for normal road use.

I'm interested in how you finished up with the track day rubber and wheels.

Do you mind if I ask what you ended up doing ?

BryanF

 

no probs. i spent a bucket of time on this.
if you want great flexibility in Tyre choice and the "option" of ever running slicks, buy an 18" wheel.
the 997 Gt3 cup car series here runs 18"s. i figure that means the car will handle just as well on the right 18 as the OEM 19.

the issue with 19" is that, whilst i think you have options for rims that look better (i realy like the champion wheels), you have 3 tyre choices. Michelin PSC NO version, P Zero Corsa (System), Hoosier R6.
The Michelin is an outstanding road tyre and a good track tire but for porsche supersprints or the like, it needs too long to warm up (common comment on this forum) which i agree with, and in Oz, they are $2700 AUD a set. The P zero's are awesome in Corsa but not in Corsa System. the rear size is not available here yet in Corsa (not corsa system) = big difference.
the hoosiers are available in 19 although the rear is a 295 only (wich is right on the edge of the fitment range, and some would say outside the fitment range, of a 19 x 12 inch rear rim. ... and you will need to trailer the car with Hoosiers. the ONLY issue i have found with the stock Michelin is the warm up time. takes 2 laps...

There will be plenty more 19" tyre choice in 2008 i think.
for now, if you want to access some longer lasting or different rubber, you need 18's.

We have Toyo R888, Hoosier R6 (in 315 rears), Yoko R compound, Michelin PSC, P Zero Corsa and Dunlop DS03G available in 18" as well as Michelin and Pirelli slicks (at realistic prices).

I acually spoke to a professional Gt3 race car driver and he had 2 items of advice. he said (a) go 18" and (b) make sure you get a rim that is within a couple of mm offset of the OEM 19.

a few guys in the porsche club have run with Simmons race wheels. they are very strong, ultra lightweight and local, ie, if you have an issue at an event, you will be able to get another wheel or a wheel repaired very quickly.
i went 18 x 8.5 frontand 18 x 11 rear. i should have them this week. i was planning to weigh them and post some pics. i think they will be under 10kg or even under 20lbs each.

Tyre wise - i will run with a set of Toyo's and Hoosiers and see how i go.
We have the perfect front end fitment for Toyo 235/40/18 (better OD than the US fitments of 245/40/18) but we dont get the 305/35/18 rear. i hav gathered from a Gt3 race driver that the 295/30/18 rear is actually ok on the Gt3 as it is 2WD. regradless, i am trying to import some 305/35's. hard to get someone in the US to ship to Oz other than tirerack who dont carry the toyo....


anything you want to know - dont hesitate to ask.
one other thing - make SURE you get your car wheel aligned and camber set BEFORE you track it.

my car had ZERO negative camber from the factory and understeered badly until i had it checked.

start with that and then move to the more aggresisve race setup in the owners manual (neg 2.5 deg)

by the way, no need to put Pilots on for the road. the OEM tyres are incredible for road use. even in the rain.

cheers

yss

 

YSS,

Thanks for the informative post mate ! Just what I needed !

PN-

 

I use the stock rims and tires for everything but the rain, which does not happen here often anyway. I enjoy the cars feel with the MPSC's both on and off the track. I may put a set of PS2's on in Nov. when I drive across the country (2000 miles each way) to Rennsport in Fl. The MPSC's last about 3000 miles. In the summer (no track days) I use the street align. and the track set up in the winter.

 

YSS

Thanks for the comprehensive detail.Can I ask what settings you have set for the front and rear sway bars.

My rear was set hard and the front 2nd softest.The rear of the car would buck and move around under acceleration around bends and curves...very unsettled.

I've moved the rear to soft and the front to the 2nd hardest and it has improved its road manners..but am interested to know what your running.

Many thanks

BryanF

 

i cant remember the front setting but rear was set hard.

it was like dancing with the car. very very skaty. 8 tenths felt like ten tenths...

did u change the rear to full soft?

 

I have ceramics. What do you suggest? Iam not at the limit yet on the cups and found that with low pressure they are good. My next set will be heat cycled and shaved.

 

YSS

I've changed the rear sway bar from hard to soft....It now handles better and is a lot less skatey. The front bar was moved from the second softest setting the the second hardest.

The mechanic that looks after Jim Richards said that the rear bar should be on soft for road driving and only on hard for high speed smooth race tracks. I'm attending my first track day on Aug 26th and will see how it handles !!

 

exactly what i am doing, just chepaer wheels than BBS.

 

What tire pressures (hot) are you using, I have OEM wheels and tires for now. I just returned from a HPDE day at Sebring and just can't believe how well the car drives straight from the factory. Photos/video coming.