My Mach 1 was born with a 3spd TopLoader and 3.00:1 open diff (not going to lie ...that combo sucked)
A while back I swapped in a 1993 or so Tremec T5 (I love it BTW) , but the performance is still pretty low....so this year I am going to get a whole complete center section for my 9" rear diff and I'm vacillating between the the 3.50:1 , 3.70:1, and 3.75:1 Eaton TrueTrac helical-gear carrier (the TrueTrac is what I am going to go with)
What are you guy's thoughts?
the T5 should have these gear ratios
1 - 2.95
2 - 1.94
3 - 1.34
4 - 1
5 - .63 OD
UPDATE 04/09/2024) correction...my T5 is 1990 variant
1 - 3.35
2- 1.99
3 - 1.33
4 - 1
5 - .68
That taller 1st gear with a 3.70 rear ratio, might be much....3.70X 3.35 = 12.395:1 effective ratio
I've been playing with this calculator to see what some of my numbers would be.
I have an old Stewart Warner tach from the 60s on the steering column that I am suspect of in regards to accuracy.
Also note: I am running too small of tires 225/60r14......which should be around 24.6" diameter
I'll probably go to a more appropriate tire size of 225/70r14 ....which should be around 26.4" diameter
I'm looking for off the line quickness than top speed or 1/4 mile speed....more like better 0-60 times....(right now it is super embarrassing, but I still get thumbs up, because of the car, not its performance)
Thanks
A while back I swapped in a 1993 or so Tremec T5 (I love it BTW) , but the performance is still pretty low....so this year I am going to get a whole complete center section for my 9" rear diff and I'm vacillating between the the 3.50:1 , 3.70:1, and 3.75:1 Eaton TrueTrac helical-gear carrier (the TrueTrac is what I am going to go with)
What are you guy's thoughts?
the T5 should have these gear ratios
3 - 1.34
4 - 1
UPDATE 04/09/2024) correction...my T5 is 1990 variant
1 - 3.35
2- 1.99
3 - 1.33
4 - 1
5 - .68
That taller 1st gear with a 3.70 rear ratio, might be much....3.70X 3.35 = 12.395:1 effective ratio
I've been playing with this calculator to see what some of my numbers would be.
Spicer Transmission Ratio RPM Calculator
Use the Spicer Transmission Ratio RPM Calculator to determine your engine’s RPM based on the transmission gear ratio, tire height, MPH, and ring and pinion gear ratio.
I have an old Stewart Warner tach from the 60s on the steering column that I am suspect of in regards to accuracy.
Also note: I am running too small of tires 225/60r14......which should be around 24.6" diameter
I'll probably go to a more appropriate tire size of 225/70r14 ....which should be around 26.4" diameter
I'm looking for off the line quickness than top speed or 1/4 mile speed....more like better 0-60 times....(right now it is super embarrassing, but I still get thumbs up, because of the car, not its performance)
Thanks
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