Tire question

[87Fbird]

What's the biggest tire you can fit in a stock wheel well on a third gen Firebird and what backspacing do i need? 15 in rims.

[98tadriver]

i think i had 275 60 15s (28" i believe) on it before but it rubbed. id say 27" would work fine. 255 60 15 is 27 i think. might wanna check it out on www.f-body.org/gears for tire calculations

[87Fbird]

I have 275/60/15s on it now and they don't rub. I was wondering if i can go bigger than that. I just got a pair of 295/65/15s for free. I was thinking maybe I can tub it out with a sledge hammer if it was too tight. :lol:

[87Fbird]

275/60s are 27x9 and the 295/65s i just got are 29x10. If they fit they'll kill my 60 ft times but pick up some mph. What do you think?

[NJSPEEDER]

I think all that extra tire height is gonna kill your car. You are giving up a bunch of torque multiplication.

Unless you are doing something like changing rear gears or adding a bunch of power to compensate you are fighting against your own cause. The idea of drag racing is to be quick, not fast. You have to pick up a ton of MPH in the traps to make up for losing just a little ET in the first half of the track.

[98tadriver]

id use the smallest practical tire thatll work with your application. something that will hook, yet still let u go thru the traps with a few rpm to spare. going up and down in tire size is kinda similiar to changing gears in the rear. all depends on the motor, trans and rear

[mc73nova]

My brother (camaroAl) runs 29x10's on his car, not sure if he altered anything though. I'm sure he'll comment once he see's this.

[NJSPEEDER]

Your bro has the power and gear to support such a tire though, this is just about going from one tire to another just because they are available.

[87Fbird]

I plan on getting a 4.10 gear real soon. I checked out that tire calculator and with the 275/60s it'll work out well. I have the 3.23 ratio now and my best 60 foot times were with a 275/50 tire but my best run times are with the 275/60s. I'll stay with the size i got, I can get them to hook. I'll work on getting some more gear.

[87Fbird]

275/60s are 27x9 and the 295/65s i just got are 29x10. If they fit they'll kill my 60 ft times but pick up some mph. What do you think?

My bad, Ron, you were right on the tire size. I was measuring worn down tires. Never mind my numbers.:-?

[BigAls87Z28]

295's wont fit teh 7 inch width. You'd have to find somethng with at least 8 inch rim width.

[mc73nova]

Your bro has the power and gear to support such a tire though, this is just about going from one tire to another just because they are available.

His first post just asked if it would fit, I was just saying it could be done, although you are right it might not be the best application for his car.

[camaroAL]

u can fit up to a around a 9" slick in a third gen with plenty of clearance. u can fit up to a 10.5 with a little trimming, in all honesty it can be altered in around an hour with almost no $ out of pocket.

[JSPERFORMANCE]

28 x 13.50 15 on my 88 IROC with stock wheel wells

[98tadriver]

My bad, Ron, you were right on the tire size. I was measuring worn down tires. Never mind my numbers.:-?

lol ok good, i thought i was slipping a lil bit haha

[camaroAL]

28 x 13.50 15 on my 88 IROC with stock wheel wells

slick? what brand? what rim backspace and offset?

my tires are stuffed in my car and almost hit the inner wheel wells and the quarters, i had to do some molding and trimming to get them in and they are 29x10-15's . ive built 4 third gens as drag cars and was never able to get a 13" slick even close to fitting. just curious on how u made this possible.

[JSPERFORMANCE]

I am just that good....

[camaroAL]

I am just that good....

and i can walk on water....

[JSPERFORMANCE]

You got those sneakers with the pump in them or some Nike Air Maxes with the bubble in the sole?????

[87Fbird]

slick? what brand? what rim backspace and offset?

my tires are stuffed in my car and almost hit the inner wheel wells and the quarters, i had to do some molding and trimming to get them in and they are 29x10-15's . ive built 4 third gens as drag cars and was never able to get a 13" slick even close to fitting. just curious on how u made this possible.

Yeah, what backspace will put the tires far enough in there without rubbing the inside, 4 1/2, 5 1/2? I have a 3 1/2 bs now and that's plenty of room, more than needed.

[camaroAL]

Yeah, what backspace will put the tires far enough in there without rubbing the inside, 4 1/2, 5 1/2? I have a 3 1/2 bs now and that's plenty of room, more than needed.


i believe 4-1/2 is what im using. ill double check and let ya know.