Iridium

I've been digging through every wheel thread I can find, and running an 18x10 in the rear is well documented, but I can't seem to find anything on running one up front. I've heard about three or four racecars (stock body) running them, but haven't found any of the info.

Anyone chime in? Use would be on a race car with lots of neg camber, but stock bodywork and coilovers.

Trying to see how I can run 285's all the way around, or at least get close. But heard about a few people running 285/30/18's all the way around...

Anyone running 285's square?

gt37vgt

her is a handy link http://members.rennlist.com/951_racerx/
i think its a good idea and I'm looking at it at the moment I have cup 2 11 and 10 but I'm thinking of trying to trade the 11's for hollow 10's
I think i will be shooting for 245 or 265 front and 265 275 rear a stagger is very effective in the wet
I may even just go 245 all round as there are much better deals on tire made for big cars here it is still good to have wide rims with 245 tire as it makes the tire very stable

Lorax

i'm going to be running 255 and 275 on my new wheels, i was running 245 all around before.

gt37vgt

hey Lorax we would appreciate you alaborating with wheel size off set/ spacer and car year . how many finger clearance and finger fatness

HansB

I do run 285 F/R.

I have posted before that IMO for a 300WHP track car this is an ideal setup.

But that is on a widebody. I could also run 305's.
On a standard body the rear fits, I am not sure about the front

gt37vgt

ok that seems big...... many of us more armature types don't see more than 10minutes per track session.
Hans how long does it take for those to come up to temp and the tire pressures to come up ?
and you are in a cold climate Hans ?

Weston Dillard

I have run 18/10 65 on front with 275. 285 would fit fine too. My car has no fender liners and the front fenders have been rolled. I then employed the very professional and scientific method of grabbing the fenders by hand and pulling them out a bit wider.

West

DDP

Amen, brother.

ritzblitz

haha maybe I should try that with my fenders!

hp18racer

The same setup that works for West doesn't work on my car. I don't have camber plates and my springs are 2.5" diameter. W/O camber plates, if you dail in a bunch of negative camber you loose a bunch of wheel clearance. With 2.5" springs, no camber plates an 18x10@65 doesn't clear the springs but 18X10@55 does. Unfortunately a 285 on 18x10@55 doesn't clear the fender even with a bunch of 'persuasion'. To fit the big tire you need either camber plates or wider fenders.

Weston Dillard

I do have camber plates, but I supect the real difference is how persuasive you are willing to be. I pulled them as much as I could. I was considering lengthening the support that connects the front of the fender to the tub so the whole thing could go out a bit more, but they don't rub now. The car is quite low, and pretty stiff (800# springs), BTW.

West

333pg333

There was someone on here just a couple of weeks ago who was selling some wheels on behalf of a friend of his. This guy had 285x18" all round, KW suspension and had used it for DE or AutoX.
I have a set of 4 x 10 x 18 wheels coming to me shortly that I'm going to try and fit 285s all round too.

EDIT: Here you go. https://rennlist.com/forums/944-turb...?highlight=ccw

Iridium

All good info - can those running the 18x10's go into more detail about the wheel offset? I'm running camber plates and coilovers (and about 3.5 neg) and have the fenders rolled.

Basically, I want to see if it's worth the pain to get to the 18x10, as I'm about to go down the path of wheel decisions and I don't want to do it twice. I'd love to be able to run square and be able to swap tires around the car. If it's a huge pain then figuring out the ideal 9" offset would be my next path, but I really want to get as much info as possible from those who are actually running an 18x10 - which tire sizes work, if it's worth it to even try to run the bigger wheel, etc...

Anyone have photos?

HansB

Yes, it is pretty cold (and wet for that matter) here.
One or two laps heat up the tires pretty good, I see like 140 - 160 F. Tire pressure goes up from 25 psi to 35 psi. Does take some serious work though, just cruising you do not get to these temperatures.

The funny thing is that since I converted to manual steering, F and R temperatures are the same. Before that, the F were hotter. To me that is caused by understeer masked by the power steering.

HansB

The ET value from the front wheels has to stay close to the original, ET45 to ET 50 for a late offset car. Otherwise you will ruin the geometry of your front setup, and break the carcas (if that is a correct word) of your tires. Dunlops are most sensitive to this, Michelins the most resistant.
Rear it does not matter, you can use spacers to your hearts content.