cashed

That was Dan at the very end! Irish was killing it out there this last weekend. Cheers!

C4SGRPDK

It's a nice tire combo! fronts are a little wider than oem and the rear are pretty much the same width as oem.

However it does drop the car more in the rear (-1.9in) than the front (-1.1 in).

if you went with 235/345, you would retain the electronics, very slightly wider fronts then oem, much wider rears (0.9 in) and the front rear height drop would be more even, -1.7in up front and -1.9 in the rear.

C4SGRPDK

That video really makes me want to go drive COTA!

m3irish

I'm curious if you have actually read my posts.

m3irish

Thanks for the kind words. 157 or so back and 138 front. Mark's car was definitely getting a higher MPH than mine with the exhaust mods.

C4SGRPDK

this one?

Here's the video I promised. 2016 GT3 RS with:
HRE R101s 19x9.5 19x12

Hoosier R7s 265/35-19 and 325/30-19

yes I have, it says you run essentially the same sizes as the GT3.

I went back through my post and I made a mistake, The people I know are running 345's tire, in the rear, not 325. My apologies, I will go back and correct that!

So to summarize,

265/325 TC & SC works as shown by m3irish

235/345 TC & SC works

265/345 TC & SC does not work.

m3irish

I apologize for giving you a hard time. What do you mean when you say "the same size as the GT3"?

Wouldn't the 265/35-19 and 345/30-19 have a smaller change from stock than the 265/35-19 and 325/30-19 that I ran? I'll likely order a set of the 265/345 for my track day at the end of the month to see how that goes.

As a side note for those looking to save money going to R7s over the factory tires. Yes, you go faster and the tires run out faster. There's no savings from what I've seen. More expense actually. Although, I told, and still try to tell myself it was an economical decision to go 19s.

C4SGRPDK

Don't worry about it! We're just trying to get the right info out there to help others. The more discussion the better!

It's exactly the size I'm running on my 991 GT3.

I think the problem is not the width of the tires but the diameter.

OEM front are 27.3 inches in diameter

OEM rear are 28.7 inches in diameter

hoosiers 235 are 25.6 inches in diameter so 1.7 inches lower than stock fronts

hoosiers 265 are 26.2 inches in diameter so 1.1 inches lower than stock fronts

hoosiers 345 and 325 are 26.8 inches in diameter so 1.9 inches lower than stock rears (I know, 345's should be higher than the 325 but as per hoosier specs they are the same diameter.)

I think it's that height difference that throws off the TC and SC.


You and me both! 19's only get you a faster tire, not a much cheaper one

C4SGRPDK

Reading my post I realized you are right, since you ran 265/325 and it worked fine, there's no reason the 265/345 combo should not work since the 325 and 345 have the same diameter

let me ask around and get back to you

C4SGRPDK

found this in the mean time, maybe supremepower can give us more info on that RS as it's running 265/345?

https://web.stagram.com/p/BPz_JL3FdQ2

m3irish

Figured I'd throw out a little more data. Running the R7s (23ish psi cold and low 30's hot) with -2.7F and -2.9R camber worked ok. Front roll over looked great. The rear could use a little more roll stiffness or added camber as the wear was going further down the shoulder than I wanted. Same story with the stock Dunlops.

It did seems like the rear was struggling grip wise in steady state cornering and putting the power down on exit. Rear sway was set to full stiff with the front on full soft (front end feels good). I'm thinking about going to medium on the rear swaybar and adding another -0.3 of camber in the rear before the next track day for some added confidence.

EST

Manthey RS...
Interesting rear wing angle and look under the back of car as well...
Any information how this rear wing angle is achieved ? (Drilling some new holes...?)

TRAKCAR

^^ Strange, I think it has plenty of downforce. if I add anything more it slows the car down too much in the straights..

RS time is too be had through tires and suspension me thinks..

EST

Good point, I am changing the suspension, not tiers (possibly trying Trofeo R's)

Metzeger

WOW the wing angle!! possible on stock GT3 RS wing? and you see the R diffuser also?