275 tires and 18x11 vs 18x10 wheel fitment on stock shocks

[spaghettihoes]

I run 18x10 ET30 Apex wheels as my track wheels with 275/35/18 RT660 tires.

The RT660s run about a size wide and I ran into clearance issues on the front spring perch just barely rubbing and the plastic front upper fender liner was ground up from the tire hitting it on hard compression. I ended up running a 3mm spacer which stopped the rubbing and once the fender liner melted off it wasn't a problem anymore. If you're running a 200tw that runs wide, I might suggest moving down to 265 instead but it did work and felt good on track.

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[razorlab]

I run 18x10 ET30 Apex wheels as my track wheels with 275/35/18 RT660 tires.

The RT660s run about a size wide and I ran into clearance issues on the front spring perch just barely rubbing and the plastic front upper fender liner was ground up from the tire hitting it on hard compression. I ended up running a 3mm spacer which stopped the rubbing and once the fender liner melted off it wasn't a problem anymore. If you're running a 200tw that runs wide, I might suggest moving down to 265 instead but it did work and felt good on track.

Have any photos of the RT660's on those 18x10's?

 

[Mad0zodi]

Yes, I was referring to WWT/Gateway. It looked pretty uninteresting to me at first but I was surprised and actually enjoy it quite a bit. It flows well for a roval and short laps mean you get a lot of repetition for practice. Even in my S2000 the straights don't feel too long and I can carry a lot of speed in the oval bank. I call it "Tsukuba at home." Only down side is that it destroys your passenger rear tire so you need to rotate at the track for even wear. I've never ran Kansas Speedway and TBH the infield looks much less interesting and I've heard bad things about the road surface.

Right on. I've done more 2-wheeled track days around the WWT road course than I can remember. But, for safety reasons, the course dipped down onto the goat path to avoid the banking. I did 2 HPDEs with the StL PCA back in '08 and back in '24, after almost 10 years away from any track, I did the NASA GR freebie and added a day.

I don't care how many times I've gone through them, I don't think I'll ever be happy with my line through the banking or through T1.

I'll be puckering through Ozarks International Raceway on 3/22.

 

[Mad0zodi]

I run 18x10 ET30 Apex wheels as my track wheels with 275/35/18 RT660 tires.

The RT660s run about a size wide and I ran into clearance issues on the front spring perch just barely rubbing and the plastic front upper fender liner was ground up from the tire hitting it on hard compression. I ended up running a 3mm spacer which stopped the rubbing and once the fender liner melted off it wasn't a problem anymore. If you're running a 200tw that runs wide, I might suggest moving down to 265 instead but it did work and felt good on track.

Sorry if I missed it, but is this on stock suspension?

 

[tsaulsbu]

I expect he is talking about stock suspension given the reference to clearance issues with the front spring perch. As another datapoint, 275/35/18 Continental ECFs on an Apex 18x10 ET30 work fine w/ a 3mm spacer up front.

 

[Shift9303]

Right on. I've done more 2-wheeled track days around the WWT road course than I can remember. But, for safety reasons, the course dipped down onto the goat path to avoid the banking. I did 2 HPDEs with the StL PCA back in '08 and back in '24, after almost 10 years away from any track, I did the NASA GR freebie and added a day.

I don't care how many times I've gone through them, I don't think I'll ever be happy with my line through the banking or through T1.

I'll be puckering through Ozarks International Raceway on 3/22.

Be safe at Ozarks. If it's your first time take it real easy, it's an extremely sketchy track. Last time I was out there was in NASA HPDE2 and we have 4 cars crash over the weekend. Almost every corner is some combination of blind, off camber, or down hill and there's almost 0 runoff. I've only driven it in my S2000 and it's bump steer city. I especially dislike turn 1. Maybe the Supra will handle it better but IDK if I'll make it out there this year. I prefer to hang out with my Chicago friends at Autobahn.

 

[Mad0zodi]

Be safe at Ozarks. If it's your first time take it real easy, it's an extremely sketchy track. Last time I was out there was in NASA HPDE2 and we have 4 cars crash over the weekend. Almost every corner is some combination of blind, off camber, or down hill and there's almost 0 runoff. I've only driven it in my S2000 and it's bump steer city. I especially dislike turn 1. Maybe the Supra will handle it better but IDK if I'll make it out there this year. I prefer to hang out with my Chicago friends at Autobahn.

Duly noted. Yep, it'll be my first time. My NASA HPDE2 instructor shared some details about his particular crash while coaching shotgun, so I'm going in very wary. I've already lost too many fights against the earth/tarmac from my motorcycle days, safe fun is the priority nowadays.

I'd love to run Autobahn at some point...the other tracks I've been to are Blackhawk Farms, Putnam, and the closed-for-some-time-now Heartland Park.

 

[spaghettihoes]

Have any photos of the RT660's on those 18x10's?

I'll take a picture of the tires on the wheels off the car tomorrow.

Sorry if I missed it, but is this on stock suspension?

Yup stock suspension. I do have lower control arms with lower camber (-3 in the front) so it might be different with stock camber, but I think the negative camber might actually make the clearance worse. I'm not sure though.

 

[razorlab]

Yup stock suspension. I do have lower control arms with lower camber (-3 in the front) so it might be different with stock camber, but I think the negative camber might actually make the clearance worse. I'm not sure though.

The whole hub and strut moves with negative camber added via LCA or upper plates, so the tire/wheel clearance to strut does not change.

 

[Shift9303]

Duly noted. Yep, it'll be my first time. My NASA HPDE2 instructor shared some details about his particular crash while coaching shotgun, so I'm going in very wary. I've already lost too many fights against the earth/tarmac from my motorcycle days, safe fun is the priority nowadays.

I'd love to run Autobahn at some point...the other tracks I've been to are Blackhawk Farms, Putnam, and the closed-for-some-time-now Heartland Park.

RIP Heartland Park, it was my local while I was in KC. Now they have Hedge Hollow, but I haven't been able to make it out there yet. If you're in STL area then I might see you around. Gateway is the local but I have friends in KC and Chicago so I've been spending more time tracking with them at their locals.

Yup stock suspension. I do have lower control arms with lower camber (-3 in the front) so it might be different with stock camber, but I think the negative camber might actually make the clearance worse. I'm not sure though.

Clearance to the fender or strut? I imagine LCA shouldn't affect clearance to the strut on a McPherson car because the strut is directly tied to the hub unlike a dual wish bone car like the S2000. Typically upper pick up point adjustment should improve fender clearance since you're tilting the wheel away from the fender. Lower pick up adjustment may or may not make fender clearance better or worse depending on geometry. With the S2000 lower ball joint adjustment does improve clearance but much less than upper. With the Supra I can see LCA making fender clearance worse because you're swinging the bottom of the knuckle out with the top hat as the pivot point.

 

[spaghettihoes]

Clearance to the fender or strut? I imagine LCA shouldn't affect clearance to the strut on a McPherson car because the strut is directly tied to the hub unlike a dual wish bone car like the S2000. Typically upper pick up point adjustment should improve fender clearance since you're tilting the wheel away from the fender. Lower pick up adjustment may or may not make fender clearance better or worse depending on geometry. With the S2000 lower ball joint adjustment does improve clearance but much less than upper. With the Supra I can see LCA making fender clearance worse because you're swinging the bottom of the knuckle out with the top hat as the pivot point.

Fender is fine, although I hit the plastic inner liner on compression. I'll share in the pics. The issue is the strut perch. I actually have an S2000 I track as well that I just changed the suspension/wheels/brakes on, but as Razorlab said it's not an issue on the Macpherson struts the Supra has.

 

[spaghettihoes]

Have any photos of the RT660's on those 18x10's?

Here's the 275/18/35 RT660s on the 18X10 wheel. It's definitely a bit wider than the wheel but felt fine on track. I might go a size narrower if I use these tires again.

Here's a pic of the fender liner rubbing (probably mostly turn 2 at Thunderhill East):

And a bonus shot of the S2K with Wilwood brakes and Ohlins I put on recently.

 

[Shift9303]

That looks like the self clearancing my S2000 did to its liners. As long as it's not catching the hood/fender I'm happy.

I've pretty much decided to go with 295/35/18s and have my 18x11s sitting in the garage. Just waiting on tires, and free time to finish up this spring install.


My S2000 for sharing sake, lol.

I'm dealing with a lot of small gremlins in it though, which is partially why I got the Supra

 

[spaghettihoes]

Clearance to the fender or strut? I imagine LCA shouldn't affect clearance to the strut on a McPherson car because the strut is directly tied to the hub unlike a dual wish bone car like the S2000. Typically upper pick up point adjustment should improve fender clearance since you're tilting the wheel away from the fender. Lower pick up adjustment may or may not make fender clearance better or worse depending on geometry. With the S2000 lower ball joint adjustment does improve clearance but much less than upper. With the Supra I can see LCA making fender clearance worse because you're swinging the bottom of the knuckle out with the top hat as the pivot point.

I just went though the exercise of clearance on my S2000 for brakes, fender and suspension so my head is probably still in that space.

 

[Shift9303]

I just went though the exercise of clearance on my S2000 for brakes, fender and suspension so my head is probably still in that space.

Don't blame you. Wheel fitment on the S2000 is a nightmare, especially if you're trying to fit big chungus 17x10s.

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