[Hendo741]

Just finished my first autocross season in the my 22 M4CX and thinking about a few changes during the off season. What I would really like first and foremost in more rubber under the car. Ran this season on 275/35-19 square RT 660s, and while they're good I'd always opt for more mechanical grip if possible.

I'm wondering if i go down to an 18 if id be able to fit some 295/30-18 A052s. considering it's 1.5 inches smaller in diameter, would that offset the 1.1 inches wider tread width??

Largest issue with wider tires seems to be rubbing on the fender liner and cooler vents at full lock. If anyone has any experience with this I'd greatly appreciate it!

[moproblems]

Originally Posted by Hendo741

Just finished my first autocross season in the my 22 M4CX and thinking about a few changes during the off season. What I would really like first and foremost in more rubber under the car. Ran this season on 275/35-19 square RT 660s, and while they're good I'd always opt for more mechanical grip if possible.

I'm wondering if i go down to an 18 if id be able to fit some 295/30-18 A052s. considering it's 1.5 inches smaller in diameter, would that offset the 1.1 inches wider tread width??

Largest issue with wider tires seems to be rubbing on the fender liner and cooler vents at full lock. If anyone has any experience with this I'd greatly appreciate it!

I would not go smaller in diameter and get the correct sized tire for the car in that way. Chop up the fender liners because racecar, they are cheap.

[Hendo741]

Originally Posted by moproblems

I would not go smaller in diameter and get the correct sized tire for the car in that way. Chop up the fender liners because racecar, they are cheap.

Would be an illegal modification in street classes, so the answer is smaller diameter wheel. The non comps come on the 824Ms, so 18s will fit over the brakes. Was just wondering if anyone had tried it out yet.

[moproblems]

Originally Posted by Hendo741

Would be an illegal modification in street classes, so the answer is smaller diameter wheel. The non comps come on the 824Ms, so 18s will fit over the brakes. Was just wondering if anyone had tried it out yet.

Why not just let them rub then? They only will rub at full lock in reverse. And by running tires that fit I'm saying not going one inch lower in diameter.
Also are you looking to go 18 inch squared? As comp x drive was never speccd from the factory with the 18/19 split the rear 2 inch drop in diameter does not fit within the rules. If you are fast enough to worry about a contest from heatgunning fender liners you will most definitely be contested on the rear diameter drop.

[m2michael23]

Originally Posted by Hendo741

Just finished my first autocross season in the my 22 M4CX and thinking about a few changes during the off season. What I would really like first and foremost in more rubber under the car. Ran this season on 275/35-19 square RT 660s, and while they're good I'd always opt for more mechanical grip if possible.

I'm wondering if i go down to an 18 if id be able to fit some 295/30-18 A052s. considering it's 1.5 inches smaller in diameter, would that offset the 1.1 inches wider tread width??

Largest issue with wider tires seems to be rubbing on the fender liner and cooler vents at full lock. If anyone has any experience with this I'd greatly appreciate it!

My friend in China has done 18x10 et13 with 285/30/18. I am going to try 295 when my set comes.

[nicksm3]

With my extensive research and background and figment for the track you most certainly can fit 18x10.5 square on 305 square. Now with negative 3+ camber upfront(8-10mm spacer) and 1.2+ rear you can even do 18x11 315 square