kimo964

Somewhere in here https://rennlist.com/forums/showthre...highlight=tire

Thanks for the clarification

SA Mike

I guess what I meant to say Anthony is how does Rolling Dia come into play. I noticed from this forum that the 285/30 Rolling Dia is lower than stock. How does this affect the handeling?

cobalt

The biggest factor is speedo correction and acceleration. With the stock 265 at 25.3" Overall dia you are looking at 823 revolutions per mile. With the 285 at 24.8" dia 840 and the 295 at 25" dia you are looking at 832. So this would have a 2% correction factor for the 285 and 1% for the 295. IIRC smaller dia means quicker acceleration and less top speed.

Handling is subjective I guess. There are pros and cons to any changes. Wider tire better contact patch, this is good assuming you have enough down force to take advantage. Although at the same time you have a different fit to the wheel so the large dia on a 10" wheel will give you less sidewall strength or more sidewall play in the turns.

I haven't heard any negatives from the people I spoke to. Chris my local tire guy is considered very good and he gets invited by Perelli to be a tire technician at LeMans every year. He was all for going with the 225/285 or 235/295.

I can't comment any further because my car came with the 225/285 setup to start.

cobalt

Thanks for pointing that out. Was quick typing. Shouldn't do that. Corrected BTW

One other point I forgot to mention the 235/40 295/30 MPS2's came stock and are N rated for the 996 GT3.

SA Mike

Thanks Anthony for the clarification...you rock brother

JBH

The only downside to leaving the 225s upfront and going to 285 in the rear is the increase in understeer. It is noticeable even at 6/10.

dholling13

Simple solution; more camber

graeme36s

Agreeing with Cobalt. But each manufacturer seems to lie about the aspect ratio or sidewall height of the tyre as a percentage of width. Some tyres have stiffer side walls than others it is a bloody nightmare.

turbo 3.6

Yes, i have just had a set of the new Bridgestone Adrenalin RE 001's fitted, and i must say it is like having a couple of bowls of jelly under the rear of the car, it must be moving around on the sidewalls, they have to come off.

Ag02M5

What size?

hkiang

285/30/18s look much better. I was going through the same dilemma and ultimately went w/ the 285s. I even had room to put a 4mm spacer behind the rear.

turbo 3.6

They were only availble in the stock 265 size, however heard back from supplier today, who is going to change them with the SO2's, might try to get them to send down 285's this time round.

Megatron-UK

SO2's are a great tyre; I had them on my Supra and they were really good all round.. in addition they wore surprisingly well.

Colorado964turbo

I have the 225/40 285/30 SO2's on my 18 inch HRE's. The fronts have worn very well, the rears, well they don't last nearly as long...

Bill

turbo 3.6

Yeah the worn tyres i replaced were S02's, they were good, apart from the noise. I look forward to getting the RE001's off and some new S02's back on, they were a nice predictable tyre, with good stiff sidewalls.