Tire size and gear question

I was just wondering on what tire and gear combo you guys run with the 9inch. I am plannig on 4.11's or higher. I have a 94Z28 with a M6. Blew up the stock 10inch real quick last summer and summer is coming back around and I need a new rear end. I am going with the Currie 9inch i think. Just looking for gear size, tire size, and rim size ( backspacing, offset and such)

Thanks in advance.

Depends what you're after. Too deep of a gear with a short tire makes first gear practically useless.

Did you have it at the track before you blew up the 10 bolt?

What gear ratio was in it?
What tire size?
What rpm did you shift at?
How high can the engine go?
What rpm were you at when you crossed the finish line and in what gear?

I can't tell you what to use if I don't know what you already had. Having 4.56 gears and 26" tall tires might be fun on the street but it would be useless on the track if you only have a 5000 rev limit.

My best times were with 4.56 gears, 29" tall tires and shifting at 7000 rpm. At the end of the 1/4 mile, the car is maxed right out but it wasn't made for highway cruising.

30 x 12.5 ET street on a 15 x 10 rim with 4.11 gears and 8000rpm shift with TH400. I was running out of gear at about the 1200 ft mark and pushing the motor higher then I wanted too. Good luck.

Vince

OK here is what I had and what happened.
My Z revs out at about 6800. I had BFG DRs 255/50R-16 with stock rear end fitted with brand new set of 4.11s. First run I ran a 12.98 and the second run I dropped the clutch and KABLOOM! I went nowhere. The rev chip is a 6800. I usually try to shift at about 6600-6700rpms . And if i remember correctly I was just at the end of 4th gear. My suspension is completly stock. I want to get the best tire/gear combo with out banging too much away from the fenders if I don't have to. I also want it to look nice and fit in the wheel well. So let me know what you think! Just looking for gear size, tire size, and rim size ( backspacing, offset and such). Oh ya I think I want the ET Streets on a 15 in rim. Thank you!

Sounds like all you need is a 26" DOT tire. The wheels can be 15x8 5.5 to 6.0" backspace, or 15x10 7.5" BS if you want to plan for future upgrades. With a 26" tire, and 4.10/4.11's and an M6, you will be at 125mph at 6,625rpm in 4th gear.

here is a decent gear, to mph calculator.
www.f-body.orq/gears

it lets you put in your gears, tire size, rev limiter... stuff like that.

So would the 28x10.5x15 et street fit on a 15x10 with the 7.5 backspacing .Or do you think that I would be better off with the 26 inch tire. I do plan on adding the suspension stuff this summer too. I like the stuff from BMR. I do have a big list of mods that I still want to do this summer. And one of these years a stroker with an ATI. By the way that link didn't work!

So you had a 26" tall tire with 4.11 gears and shifted at 6800. That sounds about right. Finishing at the end of fourth which I assume is the 1:1 gear is perfect.

If you go to a 28" tall tire, you could probably get away with the 4.11 gears but 4.3x might be a better choice. 4.56 may work but they also may be a bit too deep or you'll have to shift at a higher rpm.

Be carefull about tire sizes. What's on the sidewall isn't always the true size. A MT ET drag 28 x 9 is actually 27.3" tall. A MT 29.5 is closer to 30" etc. You can check all the tire specs on the tire's web pages. MT, Goodyear and Hoosier all list the tire specs.

For drag racing the best thing to do is squeeze the tallest tire possible into the wheel wells then adjust the gearing to compensate for the rpm range the engine works in. Tire width is a secondary measurement. Too wide a tire increases rolling resistance if the engine doesn't have enough HP. Stock eliminator cars run low 10's on a 30 x 9" tire.