Just got some ASA JH3 16x7.5 ET38 wheels and I'm looking into some ultra high performance summer tires to run for autocross.
Right now I'm at stock ride height, but I'm looking to run Koni Yellows with NM RS lowering springs in the future.


I'm looking at the following possible size/tire combinations:

225/45R16 Dunlop Direzza ZII Star Spec, or Toyo Proxes R1R, etc
225/50R16 Bridgestone Potenza RE-11, or Proxes R1R, etc
245/45R16 Bridgestone Potenza RE-11

The 225/45's are slightly smaller diameter overall than my current tires, but will stick out 16mm more (according to willtheyfit.com)
The 225/50's are 15mm larger diameter, with 16mm poke
The 245's are 10mm larger diameter, with 16mm poke
Here's a quick link to the website and comparison tire/wheel I'm using.


My main question is that for autocross, which size is best? If I go too large (the 245) will there be too much sidewall flex? Are the 225/45 best because it's a smaller diameter? Also, of your personal experiences, which tires are best for autoX? All the tires are basically the same price except for the 245's, which are about $40 more per tire.

 

have you autocrossed before? None of those are going to be competitive here and be careful choosing an R1R some of them are 140 and will put you into a prepared/modified class. Here everyone is on RE71R or rival S, I run the re71r but they wear out very very fast on the street.

on a 7.5 I would not go over 205 personally, I still run 205's on an 15x8 wheel but it's 50/50 going to a 225 for me, on my r53 I would have to run spacers up front to clear the coilovers

if you are staying in DS, the fastest tire I've used is a 205/45/16 on a 16x7 rpf1 wheel, our courses are small enough I dont hit the limiter

 

Following this thread


I was running SSR C-Types in 16x6.5 last season with 205/50R16 Dunlop Star Specs II tires and was nowhere near competitive in my class (STX).


I plan on running 205/45R16 Bridgestone RE-71R tires next season. I'm wondering if I should keep using my SSR wheels or go with a wider wheel, like 16x7 or 16x7.5. I'm staying away from 16x8 because I don't want to mess around with spacers.


I'm wondering if the slightly wider rim would help with reducing minor sidewall rollover. My thinking is yes, but I'm wondering if 7.5 is overdoing it.

 

Can't help on tire size as I am running a different size wheel and only run in an X class at Porsche AX events so I can really do whatever I want to the car.

On the tire though just about everyone is running the RE71R. That is what I am running. I do not use them as my DD tires or they would never last. As is they got me through 10 events and not a complete season.

 

The Star Specs and RE-11s aren't really competitive any more. Most people I know are using the RE-71Rs, with a few still using the R-S3s. That being said, if this is your first year the difference won't matter much. As for sizes, I usually try and use the widest tire I can that's within 0.5 inch diameter of a factory size.

As a side note/question, what are you people doing to your RE-71Rs? Do you run on concrete? My RE-71Rs lasted me ~15000 miles over two years. That included daily street driving, and ~130 68-75 second autocross runs on asphalt.

 

Ive been running dirt in an old paddock and just took my car apart again, so what do
i know,,,,,,,,, thumbs,,,,,, sliding is fun and good to learn and a slightly harder tire will last a bit longer, be competitive with yourself to start. witch tire has the actual lowest rolling diameter for the pressure I would run stated numbers can be 10% off you need actual

 

Wow, lots of information here for me to look into...

I did some research, and since I plan on getting a Manic tune, that'll put me into the Street Touring class (not sure what specific one though). I looked up some rules for that class, and I'm seeing a maximum of 7.5 wheels with 225 width, 140 minimum treadwear tires, so it seems like 225's should be what I get.

Is this reasoning right? These classes are so confusing and every rule book I look at has different definitions for them.

EDIT:
Did some reading through the thread, seems like the RE-71R are the most recommended choice. Those are available in 225/50/R16, and looks like they should fit. So that might be the best choice for me.

 

launching and torque are important you have to get the feel for keeping the power on and really throwing the car around. A smaller rolling diameter will help gearing and to start with grip may not be the only thing to consider balance and power and you should slide and getting a tire that lasts long enough under the hardest abuse you can put down will help build skill, you will soon want all kinds of tires dont stress this too much

 

Not sure the total miles but this is what I got out of my RE-71's

To and from AX on the highway about 30 miles round trip.
10 AX events which are n an abandoned marine runway, each event is 12 laps at around 80 seconds average. I probably used them at minimum 1 AX too much. After the last one once I got home the cord was showing.

I can't beleive you are getting such great wear and mileage out of yours, nice. Is tread depth the same on all new RE-71's regardless of size? I am running 215/40/18

 

Sorry I forget,,, you are putting down cash and want the best performance possible and my suggestion is a bit counter to that.... So how about some used tires to start if possible and run them until they chord but again the aspect number can be 10% off and rim size changes width and pressure,,,,, the goal is most revs possible,,, grip is great,,,, balance is better and that gets into sidewalls. Once you try a few different tires you get the idea how different the set ups can be. Have you read up on slip angles camber settings etc. then you need to practice shredding tires the best compounds are great under the right conditions but they dont last long.... Does this stuff sort of make sense

 

I get what you mean, having the best tires isn't going to make me a better driver, and I need to learn how to use them to their full potential before they make me any better. I'd love to see about getting a set of used tires on the wheels first to see what size works best for my gearing. Do you know how much it would cost for the tires + mounting + balancing? The issue I have is that finding a set of good quality summer tires is going to be very difficult, and if I'm spending probably 80 bucks or so just for each tire, why not just spend a little extra and go new, better ones?

 

You will find that tires with rims for racing x ect. get sold often with a good bit left so fresh tires can be had at the end of the season around now for me in the north east. the tires are in the perfect spot for real abuse and when chorded you still have rims to keep or sell. You need to ask around because these deals are often right at the event. Next you can look for what ever is performance oriented and on sale values are about trade offs you need to dig in and think it through just dont pressure yourself into perfection yet but do try for the smaler less costly sizes first, if you are learning your goal is shredding tire destruction, the smaller sizes may be over looked by others. Civics are 100X4 and you can even get steels basset racing even though balance may be an issue. As for cost of mounting and balancing none of this is inexpensive. Once you get the bug you see real teams with tire hoards and dream.

 

If you change boost with maniac tune doesn't that put you in SMF ?

 

If you go for ST, I believe the MCS is in STX.

I'm pretty sure that's true, but I don't think there's a practical way to check for added boost at an event. In practice, it will really only matter at national level events, or if the other people in your region are very competitive. If you're not fighting for top of your class, I wouldn't worry about it too much.

TireRack says all sizes of RE-71s start with 8/32" tread. I run 195/55-16 and have the pressure set between 30 and 35 psi. When I took them off, all four tires had between 1/32" and 2/32" tread left. I drive a bone stock Justa, so lack of power probably helps.

 

reposting this question since it wasn't addressed by previous responses. Thoughts?

 

uhh this is straight up cheating, I would not do this but then again I am winning my class at most events

 

I run 205's on a 7" in DS, and a 8" in STX, they feel better on a 8" wheel to me

both configs give me terrible wear on the front tire outside edge, STX with camber is better but still -2.5 is not enough for even wear on my car. Both my sets of tires have 5/32 in the middle and most have 0 on the outer 3"

I hate how it handles with more than 38psi, but for HPDE this weekend I'm putting 40+ in them so I can get a little more life out of them

 

At this point, if you can hold off a couple months on tire choice it'll be to your benefit. the season is over, and tire manufacturers will be coming out with new stuff soon. Whatever you do, stick with 200TW tires, 140 is not legal in Street touring or stock class.

 

Hmm, that seems like the case. Granted, I could switch over to the stock tune for autox if I wanted to stay in STX.

 

I don't know what tire you're running, but if it's the RE-71, you are giving up time at that high of a pressure

 

it's HPDE so I dont really care

for autocross I like 36-38 if I go lower it rolls over onto the sidewall

 

I cant make all the events so I never go at x competitively but its a good goal. Are you used to running all the way to red line? There are different ways to going at x for me,,,, relaxed and keeping my rpms moderate and going for as smooth a run as possible x being rather tight and quick, Or going max out to redline dropping rpms to shift only its much tougher on the car but as long as I dont slide out,,, faster, if you haven't run yet you will need to start with some smooth runs and that sort of is the goal but going at it all out wont need a tune as much as the engine makes enough power its timing balance and a bit of strategy at higher rpms you will be dong well to get the power down just dont burn the clutch out

 

I thought most clubs let you throw away worst 2 or 3 so if you cant make every event you can still chase points

 

Remember these tires run wider than usual. 205 is ideal on a 7.5 with 225 being max.

As stated use RE71 or Rival S to win. Otherwise ZII and RS3 are fine to keep up or beat inferior drivers.

I like the Mini's rev limit protocol as it doesn't bounce. I've ridden the limit thru slaloms just fine.

FYI the Nexen N Fera Sur 4 is not good for autox. Fine for track day

 

I've thought of being a bit more involved but I like finding new places to try, In the north east we have like 5 tracks and I still haven't gotten up to Canada and I cant help the mod/project bug bug bug. I've got like 5 active things at once, Im so out of space Ive actually found myself with tools in hand but no place to put them down, and Ive discovered dirt and want to try some kind of rally, and in the paddock ive been trying to get figure 8's going I want to do a spiral graph and film it from above. Yes car ADD is a serious illness.