18" tires for street/track use? .. OR stick w/17"

[random hero]

Aesthetically, I like the 18" wheel over the 17", but it's pure aesthetics... I'd like to purchase a single set of wheels for the BRZ, it's driven on the weekend, and will see the track often, also see commutes of 2-4 hours to the local tracks. Because of that, the idea of a good sticky tire, but something that will last a bit intrigues me... Looking at an 18x8.75" wheel, what would be a good size tire for the BRZ? I'd like to run the Hankook RS3's, but not sure how they'd hold up on highway commutes, etc. I want a car that works well for my purpose, rather than "hella flush" or whatever the new crazy is with stretched tires, etc. I want some sidewall on the tire, the cars look great w/a 225 tire, but the lack of sidewall scares me for track duty.

OR

Do is it better to stick with a 17" wheel?? The car sees limited mileage, but maybe 2 sets of wheels would be the best way to go, 18's for street, 17's for track. ... any thoughts

[ayau]

personally, i'd stick with the stock rims and just upgrade to stickier 215/45/17 tires. this car doesn't have enough power to really benefit from wider tires. if you go too wide, then the car loses its sharp precision.

[korinfox]

Depends on how much money you have to spend on tires. If you compare the price for your choice of tire, Hankook RS3s in 255/40/17 and a 255/35/18, the 17" tires are $155 each, and the 18" tires are $259 each. Comparing closer to stock width tire sizes, you get 225/45/17 for $142, and 224/40/18 for $193 each. If you look at any other track tire (like the direzzas), it's basically the same thing, where 18" tires in the same width are massively more expensive.

18's for the street, and 17's for track is probably your best bet.

[random hero]

Well... what do you guys suggest as the best size for track tire (both 17" & 18")

[BlaineWasHere]

Originally Posted by ayau

personally, i'd stick with the stock rims and just upgrade to stickier 215/45/17 tires. this car doesn't have enough power to really benefit from wider tires. if you go too wide, then the car loses its sharp precision.

I disagree, wider is better. Have you driven the car on wide tires? I have (and a WAY stickier compound) and I think it's more precise. Personally the stock rims are so ugly I want to vomit everytime I see them. I'gm getting really sick of the facotry pained wheels fad.

Originally Posted by random hero

Well... what do you guys suggest as the best size for track tire (both 17" & 18")

Kumho and a few others make UHP tires in a 245/35/18 which would be paired well with a 18x8.5ish wheel for this car and not run a taller tire. Unless you stay kinda narrow on 18's like 225/40/18 you'll have to go taller which will kill the gearing.

18s CAN be done, but 17s give many many many more tire options at more affordable prices. I wound up going with 17x9 et42 and 245/40/17 R-S3s btw...

[CSG Mike]

I'm speculating that with stock power and stock suspension, that wider fronts may be beneficial, but rears is questionable. Why? Because the car lacks power to fully utilize additional rear grip. However, more front grip will improve cornering speed; my BRZ currently runs out of front grip far earlier than rear grip. I'll be doing some testing this weekend with 225 RS3 up front and 215 Star Specs in the rear.

FRS may be a bit different, but it seems we both have the BRZ.

@ BlainWasHere: How do your stickier/wider times compare with stock size stickier tires?

[Grishbok]

youll put up faster times on 17's in this car.

[BlaineWasHere]

Originally Posted by CSG Mike

@ BlainWasHere: How do your stickier/wider times compare with stock size stickier tires?

GRIP EVERYWHERE!

I did one AutoX on the stock tires and they were GARBARGE! Sadly I've never run stock size sticky tires.

I don't think you're going to find a reverse stagger a good thing. With the wide sticky rubber I had a few moments of lift-off oversteer from loosing rear grip. I also think that reverse stagger will hurt your ability to trail-brake into a corner as you're already asking a fair amount of the rear tires by NOT letting more weight settle back there.

Plus I was able to get to the power so quickly at autoX!

[CSG Mike]

Originally Posted by BlaineWasHere

GRIP EVERYWHERE!

I did one AutoX on the stock tires and they were GARBARGE! Sadly I've never run stock size sticky tires.

I don't think you're going to find a reverse stagger a good thing. With the wide sticky rubber I had a few moments of lift-off oversteer from loosing rear grip. I also think that reverse stagger will hurt your ability to trail-brake into a corner as you're already asking a fair amount of the rear tires by NOT letting more weight settle back there.

Plus I was able to get to the power so quickly at autoX!

The reverse stagger is a bandaid fix for the lack of front grip with the stock BRZ suspension.

We did some more testing yesterday with toe-out added to the front to the point where the front is unstable under braking, and it helped with turn-in, but the car still suffers terminal steady-state understeer.

Can't wait to get a proper set of coilovers.

We've wondered what the balance point is for tire size with stock power; 255 seems to be too much for the car, at least in the rear, while 215 is lacking...

[BlaineWasHere]

Originally Posted by CSG Mike

The reverse stagger is a bandaid fix for the lack of front grip with the stock BRZ suspension.

We did some more testing yesterday with toe-out added to the front to the point where the front is unstable under braking, and it helped with turn-in, but the car still suffers terminal steady-state understeer.

Can't wait to get a proper set of coilovers.

We've wondered what the balance point is for tire size with stock power; 255 seems to be too much for the car, at least in the rear, while 215 is lacking...

This is all at AutoX and not on a track, BUT, with 245/40 RS-3 (on stock suspension) I was able to drive the car into oversteer on corner entry but never had enough power to push the rear end around with that grip on power.

I've got KW V3's on now with a better (but not great) set-up, I'm very interested to see how much better my turn-in is, and hopefully that helps me carry more speed all the way through and then maybe I will be pushing the limits of rear grip on corner exit... Can't wait to find out!

[BlaineWasHere]

I did notice you have a BRZ, with different spring rates you might actaully have less rear grip stock.

[ultra]

If you watch the weight of your 18 inch rims + the rolling diameter of your 18 inch tires and you want a one-size-fits-all solution for street and track I don't see why 18s wouldn't work for you.

Haing said that, if you're talking about track only, max performance rims & tires then you should be able to get a lighter setup with wide 17s and tires will be cheaper.

If you just want cheap track rubber with minimum hassle and price then better tires on OEM rims should be just fine.

[UncleFester]

My advice is to get whatever you wish. Its your car. Unless you are wanting to compete on a national level, I wouldn't be too worried one way or the other. If you like the way 18's look, go with them. However, personally I bought a set of 9 inch wide 17's with a 45 offset.

-I wouldn't go any wider than a 245, unless you are going FI.

-17's will be faster than 18's both due to gearing/size and weight differences.

-18's do look better than 17's.

-RS3's are fine as daily driver summer tires. I've gotten around 12k miles and one track season on a set, same for starspecs.

-If you are going to lower your car and or make use of an adjustable suspension; expect less flexibility on your setup with 18's.

-With 18's you will feel every bump in the road, and that effect will multiply with harder springs, etc.

[Miniata]

I'd stick with 17" wheels unless you need to go with 18's for bigger brakes for track duty. 17" wheels will generally be lighter, less expensive, and turn better times than equivalent 18's, and we have very good sticky tire selection for 17" wheels.