this is where i'm headed with my 94 formula project, stock LT1 with 4:10 posi stock stall. just curious if anyone has similar combo and what kind of e.t. i can be looking forward to. i live in central florida, we race at night with 85-100% humidity, summer nights round 75*-80* pretty much just setting up the car to be reliable but still whoop some butt and have fun with

if you've got a rough idea i can go by i'd love it. 60' times esp

__________________
1986 Firebird T/A
1994 Firebird Formula

Manual or Auto Trans?

4.10's are suitable with 94+ mn6 6 spd.
3.73 is about as deep as you want to go with an auto 4L60E, 4L80.

4.10's on a stock LT1 with Auto may even hurt the ET....too deep.

Stock LT1's run about 14.4~14.2.

With sticky tires, cutting a good light, and lower gears you might shave 3~4 tenths to the upper 13's...dep on weight.

__________________
Charlie
93 1LE M29
12.30s@26mpg

This may help:

The most desired/suitable "Launch Ratio" for a street/strip car is 10:1.
Example:
My M29 has a 1st gear ratio of 2.97:1. My rear gear is 3.23:1
so, 2.97 X 3.23 = 9.6:1 rounded, or close to the 10:1 target.
If I ever change rear gears I will go with a 3.42 giving me a 10.15:1

This formula works for cars with the 24~25" tall tires most of us have. The taller the tire the deeper gear you will need obviously.

One last thing is the deeper the rear gear the harder it is on the drivetrain and a "Bonsi" Launch could result in damage.

__________________
Charlie
93 1LE M29
12.30s@26mpg

My friend has a stock lt1, auto and 4.10's he went 14.3 with a 2.6 60ft. slicks should give u around 1.9 60 ft and around 13.5-6.

__________________
Join http://fbodyracing.forumsland.com/

1994 Camaro Z28 A4 stock, 1977 Camaro built 350 410 posi.

4.10's are pretty steep for an auto car. You will burn through first gear fast with a stock height rear tire. I would suggest a slightly taller drag radial tire to knock down the effect a little bit. The ratio itself is fine for a stock motor, but as you progress it will hinder you. You NEVER want your auto to shift into 4th at the track (and it won't as long as your foot is to the floor), so basically you are running a 3 speed auto with 4.10's in back when you are at the track. I don't feel like dong the math right now, but I would guesstimate that your top speed with a standard height tire ie: 25.5"-26" tall, would be about 110 at the most, which s good for bottom 12's. Basically, if you decide to step up your motor while keeping the gearing the same, and the tire size the same, you will end up banging the rev limiter towards the top-end of the track (not a good thing).

A set of 15" rear wheels, with a 275/60/15 drag radial would effectively be like putting 3.73's-3.90's in back, plus you'd get the benefit of all that sidewall helping you to launch.

__________________


1994 Z28 Black heads/cam th350 drag car
1995 Z28 Teal 'Vert bolt-ons 6-speed cruiser