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3.73's or 4.10's?

Have a dd 87 gt with a relatively stock 5.0 and a stock aod.Just wondering what gears i would be happier with-3.73's or 4.10's?Has ac delete,smog delete,bbk shorty headers,bbk x-pipe,flow master 40 series mufflers,and a sve cai.
 

lyonmt

Active Member
Depends on how much you drive. 4.10's will give you more "jump" off the line, but will run at a higher RPM on the highway. So if this is a daily driver, something you use on the highway or a touring car, I would go with 3.73's. If it's a weekend car for beating on, a drag car or for cruising around town, the 4.10's would be recommended.
 

Kang

New Member
"They " say use 3,73s for a manual transmission and 4;10s for automatics. I have a manual and I am running 3:55s ( I didn't want to go to steep for highway driving).
 

ALMOST STOCK

Active Member
Staff member
"They " say use 3,73s for a manual transmission and 4;10s for automatics. I have a manual and I am running 3:55s ( I didn't want to go to steep for highway driving).
I've read the same thing many times over the years, and like you with a manual I also went 3.55 for that exact same reason..... and I'm happy with the 3.55's
 
Like above stated 3:55 or 3:73s if its a daily driver 4;11 if its a weekend toy. I'm running 3:73 and its pretty dang quick, although I'm running a 5 spd.
 
I'm running 3.73's with my current bolt on upgrades and 303 cam and im very pleased with the performance. I'm currently in the process of big performance upgrades but will probably remain with 3.73's (no really planning for an all out drag car). The general rule of thumb with most setups is 3.73's you will run between 2,000 and 2,300 rpm's at 60 mph and usually around 2,700 on 4.10's with a 5 spd. like everyone has said... it's all about what your plans are for the car.

research, research, and more research. you can never ask too many questions or know too much about what you're doing before you do it. and I've come to find out that it's not only the numbers that matter at the end of the day. word of mouth and personal experience is some of the best knowledge you can obtain when building on any vehicle

best of luck :)
 

87_notchfox

just another notch among the rest lol...
i got 3.73's on my coupe with a T-5 and i like it. its got enough get up with them and not bad on gas. going to use the same on my 89 auto coupe if i dont fine 4.10's lol
 

FoxBodyMustangs

Administrator
Staff member
Have a dd 87 gt with a relatively stock 5.0 and a stock aod.Just wondering what gears i would be happier with-3.73's or 4.10's?Has ac delete,smog delete,bbk shorty headers,bbk x-pipe,flow master 40 series mufflers,and a sve cai.
I think you will be happy with 3.73 in an Auto for DD.. I just dropped 3.55 and could have went a little bit higher...
 
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