so if u have 3.73 gear it will help you get 42.01mph quicker than 3.31 gear hit 47.35mph? what if the tune unlock the stock top speed limit? what is the highest mph if the gear is 3.73?

 

Yes, I'm sure you will get to speed faster with a shorter gear (3.73) than you will with a taller one (3.31).

You can tune the rev limiter higher, but your OEM valve train will not handle much more than 6500. That is not advisable.

Fastest speed in 5th gear (manual T3650) with stock tires @ 6500 RPM = 211.33 MPH, but you don't have the HP to pull the car that fast in 5th gear (.67 ratio)

Let's do this theory in all gears assuming 3.73 rear end gears @ 6500 RPM and stock tires. All speeds are max @ 6500 RPM.

1st gear = 42.01
2nd gear = 70.79
3rd gear = 108.08
4th gear = 141.59
5th gear = 211.33

 

With my 3.55 set up WOT:

1st shift- 30ish
2nd shift- 60ish
3rd shift- 85ish
4th shift- 120ish

With the 4.10's I had in it was

1st - 30
2nd - 50-55
3rd - 80
4th - 110

 

i would not try it unless you feel like blowing a head gasket. that would definatley be extremley hard on the tranny. as stated. you can change that with the a tranny, tire height, and rear end.

and to raywang5, different gears in the rear end will definatley help with acceleration, i believe 4.10 gears can shave off roughly .25 of your 1/4 mile time. but will shorten you max mph.

 

Sooooo, just WHAT are we trying to ascertain or accomplish here? Ray, what is it you're trying to do?

 

im thinking if i want a 5 speed tranny swap to 6 speed with twin clutch.

 

thx alot bro.

 

If you're talking about the 2011 6-speed, the first five gears are all "shorter" than the gears in the V8 5-speed 3650. Meaning that you'd need a crazy tall axle gear to hit 60 in 1st (2.29's would probably be tall enough - and don't laugh too hard at that number because those gears were OE-standard in some GM intermediates back around 1979).

Even with 3.31's you'd be above 6000 rpm at 60 in second . . .

6-speed (MT82)
( https://mustangforums.com/forum/2005...ual-trans.html )
---
1 - 3.66
2 - 2.43
3 - 1.69
4 - 1.32
5 - 1.00
6 - 0.65


5-speed (TR-3650)
(MVMS data sheet)
---
1 - 3.38
2 - 2.00
3 - 1.32
4 - 1.00
5 - 0.675



Norm