zuptidi

I have an eg hatch making 240whp at the wheels NA..
I'm no novice to autox, i've done a few autox and HPDE events..

Thinking about getting more serious with autox in SMF class, and looking for some advice on tire/rim combo..
Right now i have some rota slipstreams 15x7 and crappy street 225/50/15 tires
I want to buy some rivals but im at a crossroads as to what to go with.

1) 15x7 and 225 rivals
2) 15x7 and 205 rivals
3) 15x8 and 225 rivals

does having 225 on 15x8 vs 15x7 make a big difference in terms of performance? especially considering my power levels..

thank You

Xian

FWIW, with that sort of power level, you'll still have traction problems on 225 Rivals. Yes, running them on a 15x8 is better than 15x7... street tires are more sensitive to "pinching."

zuptidi

what would you recommend then? 245?

sdobson910

Sub'd for this one. I have the same thing EK Hatch with 15x7 Slipstreams and shitty street tires, I'm a little higher HP at 309WHP though.

Xian

I'm not familiar with any "Honda Friendly" 245 15 street tires... from what I've seen you're basically stuck with 205/225 street tires or go to R-comps. If you go to R's then you've got a ton of 205/225 options with the right height for the front of a Civic/Integra. There's the 275/35 15 Hoosier that has the grip thing covered but won't fit under your fenders without cutting (assuming it's on a 8-10" wide wheel). Lastly, you've got a 245/50 15" R6 available but I'd expect that you'd have clearance problems with it as well and no significant upside over the 275 with the exception possibly of longer gearing.

I guess the "big" questions are how competitive are you and do you want to stay on street tires?

ReDemoN

Just go ***** out and get a set of 15x10's and a set of 275/35/15 A6's
Hehehe
Thats what I did

Xian

Just wait until I start beating you with my new whip... you're gonna cry.

ReDemoN

*Ninja edit

Bring it Type R boy

Xian

d00d. It's no fun if you don't smack talk back!!

I'm really interested in seeing how your car runs with the 275's up front. You'll have a ton of grip but all that extra width will take some getting used to. FWIW, in the wayback machine, I went from 15x7's to 13x9's... ultimately went faster but I struggled with picking up cones with the rear tires for half the season.

Black R

^ sillyhead, you don't run wide tires in the rear! No wonder you had problems.

OP, 275 Hoosiers and 15x10's are pretty much mandatory for smf.

Then you just run 225 rears and fit them in as tight as you can.

ReDemoN

Ken, I noticed at the match tour everyone running a 205 rear.
Well not everyone, I actually didnt pay attention to what Jinx ran.

speedjunkie_g35

I have a gsr swap in my 94 vx with full bolt on's (nothing internal yet) on chrome. Current tire set up are enkei RPO-2's with z1 starspecs. Just ordered some Hoosier R6 205-50-15 for my RPO's for a track only setup when I boost and am in the ballpark of 300whp

Black R

Ya you're right.

Most of the top cars came to the same conclusion - that the rear on a Honda isn't heavy enough to make the contact patch of a 225 worth the $ and weight over a 205.

I was always scared of such a huge difference in width front to rear.

Did you notice what width wheels they had the 205's on?

Xian

This was back in 04 or 05 when low/wide/square was the way... I don't remember seeing anyone even experimenting with front/rear stagger back then.

ReDemoN

Really didnt look any wider than a 7.5 maybe a 8

Todd00

OP, if you want to get "serious", then quit looking at street tires and jump straight to Hoosiers.

Otherwise, ask your local region to run a Street Mod street tire class. Ours has that and it is quite popular with the boost buggy crowd.

Franshow

You could try using some 17's which would open up much wider (extreme summer) street tire selections (check out Sportcar motion's ITR) or just use Hoosiers and stay with some wide 15's. I'm personally on 15x8 slips with 225/45/15 Rivals and I feel the the grip is "adequate" for the 195whp my B18C is making but definitely not optimal.

green ej8

iTrader: (1)

i was just thinking about this too. 205 50 15 federal rsr feels good till they heat up, i over work the front tires

zuptidi

well now i'm considering with going with 15x9 TRM wheels and some rivals for now.. the 15x9 will give me the ability to go with wide r comps when i choose to..
however i'm concerned about rear fitment of 15x9 +36 rims. anybody got some pics.. or input?

speedjunkie_g35

I would prob stick to the TCM 15x8 +20 for the rear.

Black R

IMO, you might as well go 10" wide in the front, and save yourself from having to eventually sell the 9" wide when you want to upgrade.

That's all opinion though. If you don't intend to go wider than 225's up front, or don't want the expense of rcomps, then I get that.

Just know that your competitors - depending on how serious they are, will surely be on the widest purple crack and 10" or wider wheels.


No need for anything wider than 8" or even 7.5" in the rear + 205 Hoosier a6's.

Franshow

This a a bit off topic but eventually the popular rear biased setup popular with HPDE cars will not be the "best" setup for autoX due to the overwhelming opinion that a 275 hoosier in the front and a 205 hoosier in the rear is considered the "best"(reverse stagger) tire setup which would need a Front biased spring and damper setup, am I right?

Xian

You're right. If you go to a severely front tire biased setup, you won't need nearly as much rear spring/bar to balance the car out.

PS
For swaybars to work, there needs to be suspension deflection... the higher the rear rates are, the less the swaybar actually impacts roll stiffness. I mention this in that you can get a good balance with a front bias spring rate and "large" rear bar even while running a "square" tire setup. By running softer rear rates, you allow for additional suspension movement and put the swaybar into play more than if you had higher spring rates.

Black R

^ yes.

There is more than one way to skin a cat though...

*edit*
Christian beat me to the punch... Again!

Xian

LOL!! That's what happens in the land of conference calls...

But seriously, there's a **** ton of ways to get the "right" balance. If it's me, and knowing what I know now: I'd run a higher front rate than is typically accepted as the norm, slightly softer in the rear, bigger rear bar than "normal", and then use rear compression/rebound to tweak the balance.

Edit: see also the thread on three wheeling and the good/bad that accompanies it.