Not sure if HRE got my offset perfect or I got luck but I feel like I have plenty of room for 325's

 

Been using 245/315 and now 335 rivals since they came out and about to buy my third set, nothing but good things to say about them.

 

Ya the rivals are good tire. Good part about them and re-11 or 71 as well as rs-3 is they are all 200 aa tires. Scca for street car class say a 200 aa tire is the softest you can run. Companies have put a lot of money and tech into getting the best out of the dual purpose street and track tires in the last 3 years. It's a very tight tire class with the re-71 having the most grip followed right behind by the rivals. They are all street able tires and do decent in the rain at high speeds

 

i hear you. i'm not "worried" per se, since i'm never reaching speeds at which the n rating was designated to certify the tire would meet with porsche's standards for 175+ speeds ( or whatever the criteria it is they are using speed and what? NON tread separation factor(s)? )

but given that the three choices on tirerack in gt2 sizing as listed "today" and most days, i continue to stick with the pirelli for three reasons. primarily (a) it was the oem fitment ( who cares ) (b) it IS a tough dual duty tire with emphasis on "street" use and at $335 for rears! ( good deal ) and at $126?! for fronts must be the deal combo 'o the day in gt2 sizes. (c) they are priced in the middle of my once "go to" PS2 which has rears listed now at $544 EACH! which is nothing short of absurd gven they last me 5-6k miles to tread wear bars. the only other option ( unless one finds the NEW bfg rivals? ) are the toyo proxies, which to me? don't look at all much like a "street" tire. though i have no doubt that countless folks have used them with success on the "street" as they are after, all a dual purpose tire, if not "N" rated ( again, to me this matters very little ) as however, the pirelli and michi PS2's are "N" rated. for what that is worth.

so for now, in 18, i stay with the pirelli but have been swearing i would one day try the BFG rivals! perhaps, one day i will.

as for a 245/40 front? which for tracking and those wanting a wider plant? i can see that working if i understand the numbers correctly? or is that "taller"? not "wider".. i guess the "245" in 245/40 is the width"? but i reduced my front wheel from a 9 to an 8.5 so as to narrow the width, to better negotiate the extremely tight cornering i do. the wider wheel size was not a perceptible advantage. if anything, it was a half inch too wide lol. narrower was better. straightlining? wider = better

 

Rival s are much better for street use than a r888.
As for sizes. 245 is the width and 40 is the aspect ratio meaning the sidewall is 40% of 245mm. A 245/40/18 is taller and wide but most 245/40/18 are only .1 taller than a 235/40/18 instead of the .3 they calculate out to. A 8.5 is the correct width for a 245 tire.

 

I suspect that in Europe the Cup2 are way more cheaper than US

225/40/18 and 295/30/18 - 1132$
245/35/19 and 305/30/19(N0) - 1437$

how are these prices compared to US?

 

225/295 18 cup 2 are 1800+ shipping
245/305 19s cup 2 are 1950+ shipping

 

thx for that info. i may try then the 245 in front for my 8.5. good info. somehow i just know i'm not an "r888" guy. whatever that might be.

 

Ya a 245 will help reduce understeer a lot and perform better than the oem 225s. Also fill the wheel well better and look better on the car in my opinion

 

on an 18" 8.5?! really. i'm tempted to trust you on that. as to rub? I'm at LEAST -40 even closer to 50mm dropped. a smidgen lower than gt2. you sure there would be NO front hard lock rub? that would **** me off, but i wouldn't blame you. this has been instructive, as usual.

btw! i run oem gt2 size tires/wheels! 235/40 x 315/30!!

 

Ya oem spec on many vehicles run 245 on 8.5 and sometimes even 8. If you are running a 235 right now a 245 will sit .2 out on each side of the wheel and basically no taller. I think it's funny that they do that with the 235 and 245. Bascaly identical height just slightly wider

 

what is this offset?

 

yeah....i run gt2 oem sizes 235/40 x 315/30 only! but trying the 245/40 front won't rub ME the wrong way!, as long as the 245 doesnt rub the CAR? i'm good

im 40-50mm dropped already, low and and 'draggin the line already" lol..

 

You'll like switching to a 245. More grip forsure. From what I read, no one has pRobles fitting 245s.

 

Depends on the offset and what you can do with your alignment probably. I had to modify the radiator brackets with 9 +33.