Autox and daily wheel tire setup
 

Just got my BRZ and I have some wheel and tire questions. It's my daily but I also want to take it to some autox events because I've been getting into that recently. I've been looking at some 17x9 +38 Gram Lights 57cr's but I have no idea if this is a good setup for autox. Also I don't know what tires to go with. I was looking at a Falken Azenis RT615K Plus 255/40R17 but I'm not sure if that's too aggressive for the street. I'm also on stock suspension but might get lowering springs. Anything helps, thanks!

Yes, 17x9 is the standard wheel size for STX competition. The falkens aren't very sticky but they're affordable and durable, a reasonable step into better tires, rt660 are stickier and faster. Both will be fine on the daily but will have some compromises like noise. 245/40/17 is the standard STX size but 255 isn't bad, more of a preference thing or trying a taller tire to mitigate the short gearing on the facelift car.

If you're not building for a class get what makes you happy. A052 are the "best" autocross tire right now but the falken 660 are basically just as quick in most cases while being cheaper and reportedly lasting longer.

Im using 17x9 57CRs. They do fine.
https://i.imgur.com/RwfDfCy.jpg

Thanks for the help I wasn’t really sure what class used what tires so I may go with the 245.

What suspension are you running?

57CR's are nice but as I recall when I was looking into wheels for my track setup there are a number of lighter options in 17x9 (may matter depending on how competitive you want to be).

CS/DS - oe sized wheel, either 17x7 or 7.5 +41-+56, either 215 or 225
SSC - 17x8 +40 or higher, 225/45/17 rt660 spec tire, need spec suspension
STX - 17x9 any offset, tire <265, a052, rt660, BFG rival s 1.5, 245/40/17 is typical but other sizes may work well
DSP and up - the widest wheels and tires you can fit, either a7 (csp/DSP, sm) or yokes for XSA

If you're on the stock suspension right now and 'might' get lowering springs, you probably don't need a 17x9 with a 255.

With autocross, you really have to think about what class you want to go with. If you're just getting started, get some 17x7 wheels and a good 225/45/17 to learn on. Something like the Conti ECS for even those Falkens you mention. Get out there, have fun, and learn in a street class.

Worst thing you can do is slap on some 255's for multiple reasons. First, this bumps you to STX, which you'll instantly be noncompetitive in and will probably lose interest in autox as a whole. Second, the 255's a wide tire, thus covering us driving mistakes - but admittedly not as bad as running 255's in a super sticky tire like the Yoks/RT660's. Third, 255's weight a good bit more than 215/225's, so even though you're keeping the wheel weight the same, the tire weight goes up, and being on the outside of the wheel setup, the car will be slower in a straight line now too.

Lowering spring comment too - most lowering springs are crap. Not enough spring rate for the right height change, so you end up negatively effecting handling for autocross because it's likely you'll hit the bump stops on hard corners, effectively sending your spring rate through the roof and upsetting the car. Upgrading the struts on a 2014 keeps you in the street class and is going to give you a better daily ride too - I'd spend your money there and possibly with a front swaybar to combat the body roll (again, keeping you in street class).

If you do go the 17x9 route with 255's, just understand you're probably stunting your driving growth longer term. And if you're doing that, at least go with an STX-lite build with a header, tune, front swaybar, and coilovers over lowering springs (much better). Doesn't mean you need to build it exactly to the class, but at least that gives you a fighting chance locally at events. Again, I'd still say stick to the stock class initially.

I do get that a lot of people don't aim to be competitive and just want a car to look good with wide wheels/tires and lowering springs. But I do think it's not the right path if it's something you want to get into on even a moderate basis. I see way too many people show up with all kinds of cars, random modifications, get put in higher classes, get destroyed, and not come back or lose interest. I've also see a fair share of drivers run modified cars, rely on the car's mechanical grip, and not develop as a driver well.

Thanks for the advice. I want to be competitive but at the same time I want to correct the horrendous stock fitment. Maybe I'll just slowly try and build to a good STX set up. I know I won't be competitive right away but I'll at least get seat time.

You might also look at SSC, it's a spec class and considerably less expensive than STX. I'm on the Falken 660, it's a nice tire to autocross on and that's what the class uses.

I can not recommend autox tires for commuting. Loud, expensive, and they hurt gas mileage. Loud is the hardest part though.

Of course, I don't worry about stuffing the wheel wells... I'm driving it, not staring at it in a showcase. I use a 225/45 on a 17x8. Still on aging PSS but it doubles as my "cones are floating away, it's a lake" rain tire for autox.
Technically that's a fine wheel to use. It might have some clearance issues stock? Either spring perch or fender are the usual. Not sure. STX drivers are usually on smaller springs and a good deal of camber, so don't have fit issues.

What coilovers would you recommend? I was looking at the BC racing BR series because of the price but would they perform very good? I've seen that people are running tarmac 2's and KW clubsports but I'm not really looking to spend more than 1,500.

Autox and daily wheel tire setup
 

If you’re going to go with cheap coilovers, I’d get ST XTA coilovers. They’re the only cheap set that are TUV approved and they’re made by KW. A good alternative would be the CSG coilovers by Tein.

Save up and do it right the first time. T2 or KW V2 are certainly quite good options and also do well if you DO run them where roads are salted. There are plenty of other options - lots of this available over in the Track/Autox section here.


If you really want to go in at $1500, keep an eye out for something used, or consider the options Yosh provided.