cwylie

Currently running Mickey Thompson 275/60/15 ET street Radial pro tires but I have seen far more people running the 325/50/15 tires on C6's. Has anyone run both? Which did you prefer? Mostly used for roll racing but it would be nice to he able to hook this car up in 2nd gear.

95vettski

No direct experience, but I would say the 325r will offer more traction.

Unreal

Haven't ran both but the few people I talked to said the pros hook better at 1/4 mile and prepped track. That is to the older ET street 325s. The new ET street Rs are same or better than the pros.

advancivic

I've ran 275/60/15 never had issues hooking plenty of 900+hp cars running that tire hooking with it

Dude_man

Suspension and alignment

cwylie

Slightly positive camber and no toe at ride height right? How high are you setting the rear of the car? Fender to ground or center of hub?

Dude_man

.2 + 0 toe. Not sure on height, but mine is pretty high because it squats really hard. If I were staying irs I would be getting Vikings double adjustable struts

Unreal

My car is zero toe,+0.2 camber, and viking DAs front rear set for decent squat. Zr1 rear bar, no front bar.

robert miller

For the track 1/4 are the 1/8 mile the 275 hands down.

da6speed

To add to what Unreal stated.. The Pros worked better than the old MT street radials. But the Pros and now the newer ET Street R & ET Street S/S all have the same R2 compound. I know RPM's red C5Z ultra car has been like 1.16 60' on the new 275/60R15 S/S.

Undecided07

Anyone running the 275/60s on a narrow body car? Pics if you got'em. Currently running 275/50s & would like the larger footprint if it'll fit. TIA

1MEANGS

325/50/15 em street R is the tire you want.

Unreal

Disagree. Too many slow their cars down by over tireing them. He should be faster on the 275. He doesn't have enough power to need the 325.

1MEANGS

Your correct the 275 tire is a lighter tire... but for the street where the prep isn't going to be like the track the extra width of the 325 will help... the 325 tire height is 27.8 (28 inch tire) and the 275 60 15 measure to 28 inch so technically the 325 is shorter tire so if anything the 275 will be "over tiring" the car but in reality they are both considered 28 inch tires. I have a lot of experience with the 325 et street r on my buddies ZR1 both on and off the track... we had the 275 tire on, we are faster on the 325. I know I know cars have been stupid fast on a 275 blah blah blah but I have a real review of that 325 R it just plain out is a work horse!

cwylie

So the 325 is hooking better on the street. I had no chance of hooking 2nd before from about 35-40mph even at just 14-15psi of boost. It will hook 2nd now at 17-18psi. I have not tried to go higher than that. It could have been old warn out 275's.

How much HP would you say you need to really use a 325? This car makes 1100rwhp and over 1000tq at 21 psi. Being turbo I can make a boat load of torque pretty low if I would like to. I have to ramp to boost in to even give the tires a chance to hook.

1MEANGS

You have plenty enough power for the 325... order it and don't look back... a 28 inch tall tire is not "over tiring" a car with that much power. My buddies ZR1 makes no where near that and he is loving the 325.

Unreal

For some reason I thought this was a 750hp car. Ignore my last comment then.

My bad.

cwylie

What are you guys using to balance them if you are balancing them at all? The shop put some sticky weights on there but the a-arm pealed them off. I think I might need to put them closer to where the caliper is.

Undecided07

You'll definitely have to move them in board from where the control arm rides. I had to remove a fair amount of material off of the lower control arm just to keep the wheel from hitting it. The lower the car rides the more material has to come off. I had similiar issue on the front with Alumastars because I've got a Z51 optioned car.

95vettski

Yes I had them static balanced with the weights in the center of the wheel. I drove around with no weights, but anything over 70 vibrated. With the weights it's better but I'm still not happy. I could see the tire hop up and down while balancing.

This is apparent when the car has been sitting overnight. For the first five minutes of driving the tires feel out of round and get slightly better once they warm up. Not sure if my tires are bad but I'm hesitant to buy another set.