wickedstang321

Would 4.10's or 3.73's or 3.55's be better with this setup and why?

(1990 Mustang LX 5.0)(5 Speed) Cobra upper intake with 1in. spacer,vortech s-trim supercharger 10-12psi boost,power pipe,sct programmer/chip,b-cam,ford racing roller rocker arms,75mm throttle body,90mm mass air,42lb fuel injectors,255lb fuel pump,high flow fuel rails,shorty headers,2 row aluminum radiator with aluminum fan blade,x-pipe exhaust,Mickey Thompson Street Slicks...

mjr46

depends on your goals..if it's mainly strip and depending on tire size, 4:10's for strip ...3.73's for all around dual purpose use

minnow81469

3.73 since your running a blower setup

Tberg725

I would go with 3.73's because its a 5spd and you have boost, but than again if its simply a track only car I would say 4.10's

Portmaster

With 10-12 pounds of boost I'd go 3:55s. Blower motors make great power down low. At the strip what you would lose in the first 60' you would pick back up just past the 660' mark. I think the ET would be close to the same with all the gears but your trap speed would be much better with the 3:55s. Boosted motors don't need tall gears and high rpm.

Timspony

...I ran 3.55's for years in 10-sec. '91 GT, Vortech T-trim, 19 psi ...Not enough gear! ...Wish I had put at least 3.73's, maybe 3.90's back there! ...4.10's too much!

Portmaster

Everything you said past that was a moot point, lol

Timspony

...had to shift my car at 6800 rpm's to run those times & crossed the finish line at about 5900 rpm's...with 3.73's or 90's I could have shifted at 6200-6400 rpm's and ran the same times...my point I should have got at...

Portmaster

I had a Kenne Bell on my 02 for a short time with 4:10s. I put 3:55s in it and loved it. It seemed like it rendered 1st gear useless with the 4:10s. For a street/strip car I'd give up a tenth for the street power. I guess it really depend on the ulitmate goals for the car would be.