Prime12

FWIW here is a 265-35R18 RE-71R next to a same size SUR4G, both unmounted.







265 RE71R pinched on a 8.5 inch rim. 257mm sidewall to sidewall.



265 SUR4G on the same rim. Again, 257mm sidewall to sidewall.



I have to spray after the second run also. Even with the spraying, after run 4 or so the fronts would lose noticeable amount of grip. I run on medium grip asphalt and sweeper heavy courses.

kyoo

iTrader: (29)

oh darn. i heard the rivals are very good with heat though

just saw OP's pic of its re71rs. wtf? no abs? even then it's extreme

CaptainSquirts

iTrader: (3)

Are you able to run 265 width tires with 8.5 inch rims? Or would 255 be best? I am currently on 245's with no issues but don't want to get a size that is too big that wouldn't fit well on it.

kyoo

iTrader: (29)

i'd run 255s..i run 255 on my 9.5" and they're just about perfect

Wanted EVO IX

A fellow autocrosser who I'm friends with asked if he could try to drive my EVO. He is a good driver and drives an FR-S. Well I warned him of the "NO ABS" and this is what happens when you aren't use to having that feature. I lost a good set of RE71Rs as a result and moved on to the NEXEN.

MrAWD

I run 265s for my daily driving and they are pretty much square on those 8.5" OEM rims (Conti DSWs 06). There is nothing wrong with this setup and it would be highly recommended.

Now, when you have a choice of running any rim, you could find better fit for sure from those that are mentioned above.

When you are in STU and you can run any rim, but limited to 265s, I would run those without hesitation on probably 10.5" rims.

When you are in BS and can run any tire that can fit on those OEM 8.5" rims (on the car that has over 1,000 lb on each of the front wheel), you should go 275s to get help with all that weight as much as you can. Since they are definitively stretched a bit, 265s might be an option as well, but would not recommend anything smaller than that!

CaptainSquirts

iTrader: (3)

Is there a negative running 255's compared to 265s or vice versa on 8.5s for autocross? Sorry for taking it a little off topic.

How's the wear for the sur4g compared to the 71's?

MrAWD

Aside from a bit less rubber on the ground and quicker tire heating process...I don't think there are any!

As of the off topic part, we have B-Street topic in here, which might be an alternative...

kyoo

iTrader: (29)

none of the studies done by GRM/andy hollis support this. can you please cite any data regarding what you claim? This was true on r-comps, but on street tires (will vary depending on the street tire) this no longer holds, and the width of contact patch that best matches the width of the wheel tends to perform the best. If there are gains, they are limited at best and sacrifice things like steering feel

MrAWD

No, I don't have any date like their test to give you here. But, that GRM test is not really applicable to us here with heavy front end AWD cars. Their cars were much lighter versions and tires were properly sized to start with. Kind of like arguing whether 10.5" or 11" rim is better for 265s.

In our case, with all that weight (I have around 1,020 lb on each wheel, without me in there) in the front, the larger will be better in dealing with heat buildup that is the worst enemy of our front grip. If car would have any bad things from it, I would say don't do it. But, I have yet to see any issue with it, aside from the occasional rubbing at the full lock.

Butt Dyno

iTrader: (10)

255s are cheaper (usually quite a bit cheaper than 265s), lighter, and shorter (which could be either a bug or a feature depending on the course).

What diameter wheels are you talking about?

Prime12

Different car, but Danny Kao dropped half a second on a 40 sec course going from 245 to 285 (8.5 rims) on the fronts of his Type R. Brian Karwan tested the car with him and he had the same result.

The drop in time came from faster turn in and more mid corner grip. The Type R never had any problem putting power down even on 245s.

MrAWD

Sure! But in this case it is not only maximum grip that is important. It is also ability to keep up with heat buildup, which is something that is very detriment to a heavy front end cars. Mayor reason for Danny to try bigger tire was heat maintenance (created lots of push once tires got hot) and they proved it is better for that reason alone!