[speedy_61462]

I've never used a transbrake, what rpm do most leave at? i have a 3000 pound car , 385 chevy,125 shot of nitrous, Coan powerglide with a 3500 tci nitrous converter, 31x16.50 M/T street slicks...I also need some help with a rearend gear for a 1/4 mile,, i've been told anythong from a 4.11 to a 5.00 i want to be turning around 6500-6800 at the end

 

[speedy_61462]

make that 3300 pounds with me in it

 

[Hutch]

Converter you listed sounds very tight , some leave right on the converter (not my suggestion) but a common number seems to be 3600-4200 .

I need a HP number to fugure out what gear to suggest or what you think the ET/mph you want to run.

Hutch

 

[speedy_61462]

I'm a old circle track guy,i'm very new to drag racing... what does a tight or loose converter mean? as far as HP i would guess around 500 without the nitrous.

 

[speedy_61462]

whoa.. i'm glad i talk to you before i ran it...i was told by the local guys to hold it at 5500-6000 and relase the button...i thought that sounded like alot

 

[Hutch]

If the converter will only offer 3500 stall , that seems like its a bit "tight" for your application and if thats its rating then thats the rpm you will get on the transbrake also. A loose converter would refer to one that has a higher stall speed.

Hutch

 

[speedy_61462]

any idea on the rearend gear?

 

[stanginthe11s]

guessing on #'s looks like a 4.56 should be a good starting point ?. what do you come up with hutch.

 

[Hutch]

4.56 would be good for straight motor and put you in the rpm band you suggested. A 4.30 may be a better choice if you want to use a little nitrous and make some motor passes without too much rpm in the traps on the nitrous (1/4 mile).
The converter will play the biggest role in the performance of the car.

Hutch