18x12's 335/30-18 square

Hello! Before you call me crazy, its been done. Now I just need to reverse "engineer" (for lack of a better word) how it was done. I think this is an epic win. I know some purist may not like it but you can't make everyone happy.

I autocross my '16 in CAM-C. While 305 Bridgestone RE71's on 19x11's has done well it is time to join the others and hopefully get more grip by going to the BFG 335/30-18 on a 18x12 wheel.

Here is what I know. The stock front brakes won't allow a 18" wheel. You can mount an 18 but you need to bring the caliper in toward the hub to fit the wheel. The best part about our brake setup is that the caliper is mounted on the spindle from the outside vs a GT which bolts from the back. If you machine the mounting surface of the spindle, you can bring the caliper in. I was told they were machined about 5/8 of an inch off the spindle.

That is all the details I can glean from the individual/pictures. I know they used a different rotor from the pictures. It appears to be a 15" PP rotor but might be off a GT500? I am unsure if those are a direct replacement or not. From there I am not sure if anything else is needed.

Anyone have any thoughts? I am looking for technical feedback to make this work. I have confirmed the GT350 on 18's is fully operational and running.

I also can't obtain the correct wheel offset but from pictures the wheel fits fine and is flush/not poking. Based upon comparison of my 19x11 et52 Apex wheels. I can go to a 18x12 et65 and they will fit. The fronts will need to be spaced approx 1.5" to run square. I will be able to run 18x12 up front due to the offset JRZ shocks which give more clearance.

What am I missing? Any help is greatly appreciated. Thanks!

I would contact Terry Fair from Vorshlag since they have some experience mounting insane rubber on Mustangs.

Here is a GT with 18x12 w/335's square, might contact him for wheel specs.

http://apexjunky.com/featured/garage-files-domestic/healys-camc-esp-2015-mustang-gt/

Simple, add the AP front brakes and you're good to go

Grimace427 said:

I would contact Terry Fair from Vorshlag since they have some experience mounting insane rubber on Mustangs.

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I would but I think at one point they were pretty hush about their 19x11 offset. Not sure they would discuss something like this, but it is worth a shot.

Grimace427 said:

Here is a GT with 18x12 w/335's square, might contact him for wheel specs.

http://apexjunky.com/featured/garage-files-domestic/healys-camc-esp-2015-mustang-gt/

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Yeah, I know Dennis and offset is the secret sauce missing in that article.

TheDeadCow said:

Simple, add the AP front brakes and you're good to go

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$4k+ Essex AP vs a small amount of machine work and a rotor? LOL. That math is too far off.

rocket71 said:

I would but I think at one point they were pretty hush about their 19x11 offset. Not sure they would discuss something like this, but it is worth a shot.

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They were and still are. I would imagine that it's probably something maybe weird like 19x11 25+ front (very normal) and like a 19x11 58+ rear (total oddball). Not sure why they're so hush about it though and they say that they've made "compromises" for it to work. What those are, I have no clue. My 19x11 Forgestars are perfectly fine in all respects. My rear wheel's spokes are rather close to the rear caliper face (about 2 - 3mm) but that's all that I can think of that would be kinda pucker worthy and I'm not worried about it at all. :shrug:

rocket71 said:

$4k+ Essex AP vs a small amount of machine work and a rotor? LOL. That math is too far off.

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This solution, while expensive, represents an upgrade in the braking performance of your car.

Machining the knuckles and finding a rotor to "fit" just doesn't seem like a feasible solution due to the possibility of degraded brake performance (smaller caliper) IMO. Good luck tho, I'm interested to see what you come up with.

You should be able to calculate it with spacers and math. There is a guy on here with a GT that fits 18x13s with some love. Boardkart or something like that.

I’m currently trying to upgrade 18 inches wheels too but only with 305/660/18 or 305/680/18 slicks. The wheel guy told me the FPRS spec is running 18*11 et18 front and 18*11 et56 rear. He sounds confident so I may start to calculate the offset from here. I hope I can be more helpful.

I don't think wheels will be too hard to figure. Its the rotors that have me stumped. Trying to find the right hat offset is proving difficult. At this point, I am pretty sure it is a Wilwood rotor but not 100%.

I need to find CAD drawings or something like it of the GT350 rotor and then we are off the races to find one.

The OEM caliper will hit 18" wheels. Forgeline even said hell effin' no to 18's with the factory front caliper. If Forgeline says we're not gonna do it, that's saying quite a bit.

Grimace427 said:

I would contact Terry Fair from Vorshlag since they have some experience mounting insane rubber on Mustangs.

Click to expand...

That car is a work of art.

[MENTION=7150]boardkat[/MENTION] and [MENTION=14173]Conedodger[/MENTION] are both on 335's
We'll all be at the ProSolo this weekend in Fontana, I'm on measly
305/30/19 RE-71's but that's what the winning car at Nationals had last year

Here's boardkat's post
https://www.mustang6g.com/forums/showthread.php?t=99038