I have been through so many wide tire fitment threads on here, I can hardly keep it all straight. Like many on here I am looking for the best setup to run 275/35/18 Hoosiers (NASA Classing). It looks like 10.5 wide rims will give the best tire sidewall stability. My car has the RTErnie rear trailing links with the extra spacing, so:


Looking at something like the Enkei PF01 18x10.5 +38. With the modified trailing arms, this offset should work and leave a manageable amount of fender manipulation, correct? (2 degrees camber rear). Rears already rolled.


That same wheel in the front will have to be spacered to clear brakes/struts, but I have the AP BBK (smaller caliper), so strut clearance will probably dictate any spacers. 3.5 degrees camber front (for now).


Outside of these issues, I should just be looking at the usual stuff (hammering pinch welds etc, etc) correct?


moving to something like the NT03 18x10.5 +30 just means a little more rear fender work doesn't it?


In summary with the modified trailing arms, the 35-38 offset makes the most sense, correct?

 

This thread is worth reviewing if you havent already

https://www.evolutionm.net/forums/mo...-body-evo.html

 

Yep, been all through that and the 'Official Wide Tire' thread. Just trying to make sure I've got my ideas correct before I buy.


And a secondary question, for those of you running the 275/35/18 sizes (NASA TT/ST), would you opt for a 10" or 10.5" rim as the 'best' match for those tires?

 

Personally I'd use a 10". Granted the rear control arms aren't an issue for you anymore however the 275 hoho's fit fine on a 9.5 and would be slightly stretched on a 10 to be about perfect. 10.5 would just add more weight without much benefit unless you plan to run 285+'s later down the road, then ya i'd get the wheels that serve all tire ideas for the next several years. At this point I have rains on 17x9.5, 275 R6's on 18x9.5, and BFG R1S's to test on new 18x10's.

 

I'll say when we test fit 285s on my car I was surprised the front fitment ended up being more annoying. I have Ernie arms in the rear as well. But back then i had stock brembos and the front wheels poked out really far, surprisingly far. Camber may have helped

 

Yeah, the AP calipers are actually a fair amount more compact than the Brembo's. I suspect tire-coilover perch/spring will drive front spacing.

 

We ran 295/30 18s on 38 offset PF01's under stock/rolled fenders in the rear. We had R/T Ernie's rear control arms, but we think stock would have even worked.

We had JM Fabrications build us spacers up front for coilover clearance that worked with the Enkei hub bore so we didn't need to run spacers and hub centric rings.

Rears were relatively easy, though we modified the mounting tab for the rear bumper.

Fronts needed substantial mods to the stock fender... but it was doable.

Dan

 

So I started that other thread about a 275 on a stock bodied Evo. My issues were not the rear but the front. I have stock traileing arms with the casting flash smoothed out. I am running the 10.5 NT03s. the rear fit with no spacer and about 2 degrees of camber. The front was eter going to hit the coilover or the fender, depending on camber. Fender is slightly pulled, rolled flat and has the fender mod. a 265 fit perfect, but I can not find any. I ran a 255 on my 9.5 RPF1's as an alternative. I want to try a 275 again but I can't seem to find my pics of how much work it was going to take.

 

run a 6" spring up front and get the spring out of the way. Run the perch up, there's more room to be had. My tire comes close to rubbing the strut body.

10.5 +30 NT03's with 275's on stock body... with out trailing arms? Are you 4x4'ing the vehicle to keep it from destroying the quarters? you're 8mm further outboard than my car... and I run more negative camber than you do... with a shorter tire. Please take some pics of what you did to your quarter panel.

 

One thing to think about along with static clearance is the tire squirm. For reference, my BFG 285s on a 10" wheel moves around 3/4-1" in both directions as I just saw from this last weekend. I need to take a better video of specifically just the tire but I have plenty of marks in my fender wells where statically the tire doesn't tough with large clearances but are completely shiny.

 

should only deflect inboard a significant amount. Also running a wider wheel for the given tire helps reduce squirm.

 

Unless I go broke from buying spare parts, I am going to buy a set of 18x11+44 wheels for next year for 275-295 tires.

I still haven't decided what to do about the fronts.

The options are:

• staggered setup (+30 to potentially use as rears if I want to run a 305/315 tire on it) with smaller spacer up front,
• non-staggered setup with very large spacer,
• short spring with smaller spacer.

Previously, I had been told that I need a 4" for the short spring. I should probably just get under the car and measure it like I have everything else.

 

I don't remember if I run a 4" front spring with a tender spring up front. my memory isn't that great. I remember that I was using hypercos :P

 

My setup:

18x10.5 PF01's +38
275/35/18 Hoosier A6's

Front:
25mm JMFab Hubcentric Spacers (required for tire sidewall to spring perch clearance)
AST5100 Coilovers with 6" Springs and Tenders
Fender Liners=Gone
Perrin PSRS with Offset and CiroDesign Caster/Camber plates running 5.8 degrees caster with wheel nicely centered in the well
3.6 Static Camber
Fenders Cut and slightly pulled

Rear:
AST5100 with 7" spring and Tender
No Spacer
RTErnie Trailing Arms
2.1 Static Camber
Rear fenders rolled pretty flat and slight pull

Hoosier lists the 275 as a 10.3" tread width. They also recommend for the R6/A6 that you run a rim +/- 0.5" from the tread width. Using their recommendation that means a 10 or 10.5 inch rim. I opted for the 10.5 to keep sidewall flex down and it works great. I have 5mm clearance between the spring perch and the high point of the sidewall with no rub. No rubs anywhere after two weekends at the track on this setup.

Also if I want to try the 285/30/18 Hoosiers, the 10.5's are a better option, just have to take a HP adjustment for NASA TT3 once you go over 275 width. I've been told the 285/30 is actually an easier fit than the 275/35.

And thanks to Eric for good info along the way and the trailing arms!

 

All of the 275/35/18s list an 11" wheel as their maximum wheel size on tire rack (and I have seen that listed on their websites as well).

BFG R1-S/R1 285/30 has a LOT of tread width for a 285 and is the next fitment step from 275 tires but not quite to the 315 size. A 315 will need an additional 1/2-1" of clearance that will need to come from somewhere. I think the shorter springs up front may be the way to go but a good 1" pull in the rear will be needed to fit a 315/30.

Hoosier 285/30 or 295/30 should fit easier than a 275/35