ok i have a fully built tpi motor with the lt4 hotcam with a fully built 700r4 and a 3000 stall converter with 4.10 gears. I just blew the rear end out and before i rebuild it, i was wondering if i go from the 4.10 gears too 3.73 will i be faster in the quarter if i could get the tires too hook The gas millage and rpms dont bother me none, i wanna fly in the quarter mile and be able too launch super hard off the line. Any opinions would be greatly appreciated..

 

Whichever ratio has you just reaching redline in 3rd when you cross the line.

 

I had the same problem, so I went with a 3.90 gear from strange. Best of both worlds

 

Because of the low first gear in the 700R4, 3.73 is a better choice unless you're going to a very tall tire. Too deep of a gear with the torque multiplication of the first gear can easily overpower the tires and you'll be shifting to second very fast.

Gear ratio also depends on tire height and rpm range of the engine. As mentioned above, you want it geared so you cross the finish line at or just after you reach the red line in high gear which in the 700R4 is third.

 

3:73's simply put.

 

ok cool ty for the info guys, one more question. If i use a rear end out of a 1998 z28 camaro with posi and disk breaks will it be able too hold 400 rwhp and if so how long? I was thinkin about just spooling my stock 10 bolt and throwing the differential in the trash? Any opinions would be helpfull

 

A 1998 diff is no stronger than your 91. They both use the same 7-5/8" ring gear. They both use 28 spline axles however the fourth gen axles are longer.