im debating on 3.73s and 4.10s.
my car is rarely driven. its 94 z28 a4
my current mods are all the bolt-ons, a mild cam, and 2800 stall.
i plan on getting more things done to it but not until a year from now.

what do you guys think i should get?

 

with the A4 go 3.73

 

3.73

 

I've ran both. I liked the 4.10s MUCH better. The car went 12.0 with 4.10's and slowed to a 12.2 with no other change but the 3.73's.
I only swapped because of the future nitrous use.

With 4.10's, I was making a 3-4 upshift about 100 ft. before the finish line. Trapping 112 MPH, on the 6000 RPM shift lite.

Frank
CPT

 

I have run the 4.10 with a 700r4 and I was very pleased though I have also driven cars with 3.73 and honestly the difference was minimal of course I have driven neither on the track being and old street racer (not condoning thats a good thing to do by any means)But I was young once too and survived.

 

I've run both ... prefer the 4.10's as well (esp. for 1/4 mile racing). Unless you're planning SERIOUS mods (like nitrous, as Frank said) which will put you well into the ~110 - 120 range at least, then you won't "run out of gear" with 4.10's for awhile (you can always run taller tires, or with good valvetrain, raise the rev limiter a little more to get you through the traps in 3rd gear).

I also daily drove mine with A4 / 4.10's, and mileage wasn't even that bad ... even compared to 2.73's!

 

I would go with the 3.73s, especially if other mods are in the works for the future.

 

I would go with a 5.13 and a 33" tire