Anyone tried 235/45 Front with 275/40 Rear tires on 17" wheels? I'm wondering if RA1's in these sizes, shaved, on 17" Volk CE28N's (7.5" F, 9.0" R) would be a good setup.

 

not real sure about fitment issues, but i just tried 225 fronts and 265 rears (Bridgestone SO3)on 18s for the first time on the track. i thought the car would plough too much to be honest, but i was mildly surprised.

it did not understeer at all once cornering, and was very happy to steer with the throttle in high rpm 2nd and 3rd gear corners. turn in was not as sharp as i would have liked, but that makes me think that this would be a safe setup at the track (for me at least), as you if you are going too fast, you would scrub the speed off pretty quick.

that makes me think that 235 fronts and 275 rears would give you a sharper turn in, but still a balanced setup. BUT, i know that these tires would be too much for the car in general. my m3 with 225 front and 245 rear is just over-tyred in the rear. that was why for the track i used 235 all around, and it felt soooo much better.

granted the dynamics of the cars are very different, and the m3 likes to understeer, so this helped that issue, but considering that it is 350 lbs or so heavier, it makes me wonder.

sorry fo the ramblings..its late and i am still working...hope that helps,
bassem

 

Hi Richard,

I know JerryPeterson in PacNW run the 235 275 CE28N combo. I beleive he likes it. And i think its a good balance with the stock spring ratio. What spring rates are you running? I do seem to recall that he gets a little bit of rubbing up front but that may be more from a drop than the width of the tires. The offset on the front CE28Ns is not ideal for anything wider than say a 225.

 

Thanks Dave. I think the spring rates are 450 front and 520 rear (stiffer than but I believe similar ratio to stock), and with running the shocks at a stiff setting and with the stiffer swaybar, my guess is they should work well even though I'm about 1/2 " lowered. I also usually run -1.5 camber front. I'd also shave them to 2/32-3/32 to get the diameter close to stock 25".
Any comments Jerry?

 

Dave,

maybe it was me you're thinking of? Jerry's got a second set of stock wheels for his track tires.

I do have 17" CE28Ns, and I'm using RA-1s in 235 255 sizes. I'm on stock suspension, -1.0 front camber. I do get a bit of rubbing in the front, although now that the fender liners are tucked above the metal I think the only time they rub is under extreme conditions (i.e., spin into the dirt ).

My car has alwas pushed, so if anything this tire setup has just made it closer to neutral. It feels very good to me on the track.

That said, I do wish Toyo would come out with a RA-1 in 225/45R17; then I would consider getting coilovers and lowering the car a bit.

Hope that helps, and let us know how it works out if you try 235 275,

Ted

 

Yup, Sorry Ted, It was you i was thinking of.

I bet if you dialed in more front camber you culd reduce the rubbing up front. Also remember that as the car is lowered the camber on the wheels will increase as well. The combo of the two may be enough to keep the rubbing to a minimum.

 

Ted, was it rubbing on the inside or outside of the fender-well? More camber could make it worse if it's the inside.
Dave, I know you ran 275/40 Hoosiers on the rear 17"'s without any problem, right? I know the RA1's are a bit narrower than the Hoosiers, so should be fine then.

 

Dave, no problem; we're all rusty up here! I'm at -1.0 front, -2.0 rear now; I might consider -1.5 front, -2.5 rear, but I don't track my car as often as some people , so I don't want to go crazy with street wear.

rlaifatt, rubbing the outside, so more camber will help. A couple of the plastic clips that hold the fender liners were getting worn down from the occasional rubbing.

 

275s will rub on the rear if you are lowered wiith the CE28s. Im actually running the 235/275 shaved RA1s on 17" ce28s

 

[QUOTE]Originally posted by docofmind
[B]275s will rub on the rear if you are lowered wiith the CE28s.