firebird formula rear end help needed

hey guys i came across a couple gm's too cheap to pass up so im going to build them up decently i have a 94 firebird formula with a 6 speed in it. anyone out there know what kind of rear end gears i can put in it and still drive it down the highway at low rpm i saw a video of a corvette with a 6 speed and 4.10 gears and he was only at about 1800-1900 rpm at 75mph but who knows if it was real or not anyone have any idea?

[MR.hp]

hey guys i came across a couple gm's too cheap to pass up so im going to build them up decently i have a 94 firebird formula with a 6 speed in it. anyone out there know what kind of rear end gears i can put in it and still drive it down the highway at low rpm i saw a video of a corvette with a 6 speed and 4.10 gears and he was only at about 1800-1900 rpm at 75mph but who knows if it was real or not anyone have any idea?

Ya it's real, Maybe the Zman will chime in he has 4.10's with a T-56 6spd and I think it's around more like 1900@ 65.

[Z28SSMAN]

Moparman. It depends on what diameter tire you're going to use and what ratio 6th gear is. I'll check when I go to storage on Sat, but 1900 @ 70 is pretty close. My tires are pretty short, about 25.5 diameter and 6th gear is .50. A few 6-speeds are .65 6th gear. Either way, you"l be happy with 4.10s. If you're gonna spray, use 3.73.

[Z28SSMAN]

I took a look at it today on the way to storage and my factory tach said 1900 @ 75 and the autometer tach said 2100. A tech 2 would verify which is right. Either way, the 6 speed is a great tranny.

[Guest]

LOL im at like 3500rpms at 70 mph. id love to be at 1900 while cruising on the freeway!
old blu makes alot of noise driving down the freeway

[Z28SSMAN]

Don't feel bad bluchev, because my '71 has 4.56s so at 50 she's around 3k

[MR.hp]

Cruzin around at 3K is not my cup of tea, Thats' why I am going with a T-56 in the bird.
Cannot wait untill it's done.

[moparman]

thanks guys that was my biggest problem so far with the car hopefully soon ill get started on a motor the stock lt1 is just not enough trying to find a 12 bolt to put it in im thinking of going with a 30x9 slicks on the car i just have the 245/50/16s on it now im going to start a buildup on the car while im at school we started a drag racing team down here so hopefully i can incorporate the school alittle on the car too make some use out of the chassis dyno and the flow bench etc. anyone have any ideas for good aftermarket suspension? im looking at the umi tube k frame and control arms. also any of you chassis guys what would be better to buy some bolt/weld in subframe connectors or cut some room in the floors and weld in 2x3 tube there is alittle bit of rust in the rear foot area and the driver floor but the car is a hardtop so the damage isnt too extensive