Willow Springs Raceway w/ Hoosiers & Race Pads

[Shellbrook76]

Originally Posted by vafan13

Gotcha. Your experience with the BBS rears on front was my inspiration for trying to find another pair of 343M rears to use on the front with 275s. Figured if you got that to fit, 275/35s on a 20x10 ET34 would be fine. Unfortunately, I've so far failed to actually get anybody to sell me some.


And to anyone wondering why a 275 on the 10 instead of a 285, two reasons:

1) 275/35 on 10" should be same diameter in-practice as the stock 265/35 on 9", so no risk of issues with ABS/traction control and reduces risk of rubbing.
2) The wider wheel relative to section width should help improve steering response and initial turn-in. My experience is this thing needs all the help with initial turn-in that it can get.

I have 275/35 PS4’s up front on stock wheel. They fit great and wear perfect on track.

It’s definitely not the greatest track car, but incredibly satisfying to get better lap times and wrestling it into place.

[spiff]

I'm inquiring with Apex about another set of rears, or at least a different pair for the rear (moving up to a 10.5").

As I said before, I'd love to go 10.5" square, either 295 or 305, but for now want to see if they'll work with me on some kind of a discount since they had zero research/info prior to me buying wheels from them.

[vafan13]

Originally Posted by spiff

I'm inquiring with Apex about another set of rears, or at least a different pair for the rear (moving up to a 10.5").

As I said before, I'd love to go 10.5" square, either 295 or 305, but for now want to see if they'll work with me on some kind of a discount since they had zero research/info prior to me buying wheels from them.

Ignoring spacers, I think you could make the 10" ET25s you have on the rear fit on the front with a 275 and use their 10.5" ET22 with a 295 on the rear. People have used the M6 10.5" ET19s without rubbing so ET22 should be fine and would stick out at least a little less.

Caveat being I don't know how the actual width of R7s compares to PS4S in the same section width.

[spiff]

Originally Posted by vafan13

Ignoring spacers, I think you could make the 10" ET25s you have on the rear fit on the front with a 275 and use their 10.5" ET22 with a 295 on the rear. People have used the M6 10.5" ET19s without rubbing so ET22 should be fine and would stick out at least a little less.

Caveat being I don't know how the actual width of R7s compares to PS4S in the same section width.

The plan right now is i'm going to run PS4S's w/ 275/35 and 305/30 on the 20" BBS's, track those, and test fit the rears in the front again. If the rears fit up front with 305's i'm just gonna go all in with 10.5's all around.

[spiff]

Originally Posted by vafan13

Ignoring spacers, I think you could make the 10" ET25s you have on the rear fit on the front with a 275 and use their 10.5" ET22 with a 295 on the rear. People have used the M6 10.5" ET19s without rubbing so ET22 should be fine and would stick out at least a little less.

Caveat being I don't know how the actual width of R7s compares to PS4S in the same section width.

Apex is gonna give me a deal on 19x10.5's to test out fitment so I think I'm gonna take the plunge down that road with some PS4S's.

[vafan13]

Originally Posted by spiff

Apex is gonna give me a deal on 19x10.5's to test out fitment so I think I'm gonna take the plunge down that road with some PS4S's.

Nice! The ET22s or ET45s? I'm definitely curious to see how it works out.

[spiff]

Originally Posted by vafan13

Nice! The ET22s or ET45s? I'm definitely curious to see how it works out.

ET45's and then 12mm spacers. It's the SM-10 design in race silver.

[spiff]

Originally Posted by vafan13

Nice! The ET22s or ET45s? I'm definitely curious to see how it works out.

So switched from SM-10's back to EC7's, but in black.

Ordered the 305/30-19's !

Hereeeee we go!

[spiff]

305's coming in hot.

[vafan13]

Originally Posted by spiff

305's coming in hot.

nice! is that 2x305s, 2x275s or 4x305s? I can't tell for sure in the pic.

[spiff]

Originally Posted by vafan13

nice! is that 2x305s, 2x275s or 4x305s? I can't tell for sure in the pic.

4 x 305/30-19
4 x 19x10.5" ET 45 w/ 12mm spacers

[spiff]

Fun fun fun update!

So I bit the RnD bullet and purchased 19x10.5" ET 45 EC7's from ApexRaceParts and mounted some 305/30-19 Michelin PS4S.

Got some 12mm spacers and 75mm studs.

Threw on the first wheel with enormous excitement and of course there was rubbing- but on the inside, not the outside!

I was super bummed I couldn't just throw em on and drive, but i suspect it's the difference between having had 295's up front (from my rears) and upping it to 305's- since the off set was identical.

So I bagged em up in some tire totes and headed to the track- hoping autozone or oreilly's would have some kind of a universal spacer that would give me just enough clearance.

AND THEY DID!

I through some random White Knight 4"-5" 5/16th spacers that gave it just enough clearance. Zero rubbing on the inside of the tire after hot laps.

Man this thing drove so FREAKING well with 305's. No need for hoosiers for me anymore. These fit the bill without cording in 5 sessions. Was holding 130mph through 8 without any issues.

Here is the result:

[spiff]

On track photos, you can see the fronts tuck in nicely.

[vafan13]

That's epic, man, and great pictures! 305s on the front would feel so much better than the stock 265s on track. To be clear, did you end up with two spacers on the front, totalling ~20mm?

And what specifically were they rubbing on initially?

[spiff]

Originally Posted by vafan13

That's epic, man, and great pictures! 305s on the front would feel so much better than the stock 265s on track. To be clear, did you end up with two spacers on the front, totalling ~20mm?

And what specifically were they rubbing on initially?

Yeah two spacers on the front. Which yes I believe equals 20mm. 12mm + 5/16th which I think is 8mm?

The tire was rubbing the inner control arm. Now zero rubbing !

[vafan13]

Originally Posted by spiff

Yeah two spacers on the front. Which yes I believe equals 20mm. 12mm + 5/16th which I think is 8mm?

The tire was rubbing the inner control arm. Now zero rubbing !

Seeing how it looks now, do you think you could have fit the 305/30 on the 19x11 ET44s with the same 20mm in spacers or a 17.5mm spacer? My guess is the outside would be fine, but less sure about where the control arm was rubbing.

Another option in hindsight might be the 19x10.5 ET22s. From the pictures it seems like there might be room for the extra 3mm on the outside, but hard to tell from the pictures I'd the edge of the tire would rub as the suspension compresses.

Thanks for taking the plunge on this!

[spiff]

Originally Posted by vafan13

Seeing how it looks now, do you think you could have fit the 305/30 on the 19x11 ET44s with the same 20mm in spacers or a 17.5mm spacer? My guess is the outside would be fine, but less sure about where the control arm was rubbing.

Another option in hindsight might be the 19x10.5 ET22s. From the pictures it seems like there might be room for the extra 3mm on the outside, but hard to tell from the pictures I'd the edge of the tire would rub as the suspension compresses.

Thanks for taking the plunge on this!

Originally Posted by vafan13

Seeing how it looks now, do you think you could have fit the 305/30 on the 19x11 ET44s with the same 20mm in spacers or a 17.5mm spacer? My guess is the outside would be fine, but less sure about where the control arm was rubbing.

Another option in hindsight might be the 19x10.5 ET22s. From the pictures it seems like there might be room for the extra 3mm on the outside, but hard to tell from the pictures I'd the edge of the tire would rub as the suspension compresses.

Thanks for taking the plunge on this!

Tough to say now. I'd love to try the ET25's for comparison sake. I didn't realize how the 305's would rub compared to the 295's.

I think 11" wide in the same offset would work as it felt like just the tire was rubbing, no wheel issues.

[vafan13]

Originally Posted by spiff

Tough to say now. I'd love to try the ET25's for comparison sake. I didn't realize how the 305's would rub compared to the 295's.

I think 11" wide in the same offset would work as it felt like just the tire was rubbing, no wheel issues.

The 11" ET44s with 305/30s seem like the best bet, if one were buying now based on your findings. I'm tempted, but not sure where the heck I'd store them. Already have three sets of wheels for the Cobra.

Edit: Although I wonder if the 295/35s would have more max grip. More sidewall usually helps with that, but not sure if enough to make up for the loss in width. Also bigger diameter, but I expect that wouldn't have much impact on lateral grip. Well beyond my knowledge, though.

[spiff]

Had another successful track day in the pig. Rotated the tires the first time and man this train flies. Was taking Turn 2 at Big Willow around 90-95mph and entering Turn 8 a little above 135.

I'm on the fence but starting to swing my leg over to putting some more $ into the M5 to improve the experience.

Thinking about doing:

- KW v3's w/ EDC Delete
- CSF Charge Coolers
- Turner AxleBack Exhaust
- Dinan Intake

I'm also considering a half-cage so I can put some proper seats up front with 5 point harnesses. Does anyone have any experience with this and/or any of the above mods?

Thanks ya'll

[built.e92]

This is badass! Please keep up posted with your fitment adventure!