I already have a 4.625:1 ratio diff in my rally Starion. It has a top speed of around 170-185, depending on the diameter of the tires I am using and where I set the rev-limiter.
Regards
David
L300 diff into staz
0
doesnt really work like that
think about it like this
gearbox got ratios, so does diff
you have 400nm at the engine
goes thru say.... 2nd gear with is around the 2.8 mark i think
so 1120N at the driveshaft
4th gear would have 400N at the driveshaft (1:1)
then it goes thru the diff, another ratio
3920N @ the wheels with a 3.5 diff in 2nd
5152N @ the wheels with a 4.6 diff in 2nd (lower speed of course)
or 1400N @ the wheels in 4th with a 3.5 diff
thats just an example, gearing it what allows us to accellerate decently.
i can go thru the torque vs power thing too if you want
doesnt really work like that
think about it like this
gearbox got ratios, so does diff
you have 400nm at the engine
goes thru say.... 2nd gear with is around the 2.8 mark i think
so 1120N at the driveshaft
4th gear would have 400N at the driveshaft (1:1)
then it goes thru the diff, another ratio
3920N @ the wheels with a 3.5 diff in 2nd
5152N @ the wheels with a 4.6 diff in 2nd (lower speed of course)
or 1400N @ the wheels in 4th with a 3.5 diff
thats just an example, gearing it what allows us to accellerate decently.
i can go thru the torque vs power thing too if you want
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SpidersWeb
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To continue what CussCuss said
hp = torque * (rpm / 5252)
With a shorter diff, the torque at the wheels is increased yep, but the speed of the wheel is decreased, therefore the horsepower remains the same.
Previously on austaz there was a conversation, about the hp gains of a shorter diff ratio, but there was an extra word there, 'equivelent'. Its like having extra horsepower but there isnt actually any.
The advantage to the shorter diff ratio is purely to keep the engine rpm closer to its peak power when racing.
hp = torque * (rpm / 5252)
With a shorter diff, the torque at the wheels is increased yep, but the speed of the wheel is decreased, therefore the horsepower remains the same.
Previously on austaz there was a conversation, about the hp gains of a shorter diff ratio, but there was an extra word there, 'equivelent'. Its like having extra horsepower but there isnt actually any.
The advantage to the shorter diff ratio is purely to keep the engine rpm closer to its peak power when racing.
1997 Mitsubishi Lancer Evolution IV 4G63BT
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Oscar-the-Grouch
- I love starions
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Yeah... What he said ! :D
Seriously though.... We use the 3:90's here for street / Strip use with GREAT success. No one has tried the 4:625's yet as it just low a gear for the 2.6L that redlines at 5700 rpms. We have a member running the 4:22's and he's liking it alot for Drag racing but again the 2.6 with the lower rpm ratings it not desinged for low gears and hi speed at the same time. Yeah the 4:625's will get you there in a hurry with neck snaping torque but at the end of the quarter you will be redlining 5th gear at 6000 not good for an engine.
Later
Oscar
Seriously though.... We use the 3:90's here for street / Strip use with GREAT success. No one has tried the 4:625's yet as it just low a gear for the 2.6L that redlines at 5700 rpms. We have a member running the 4:22's and he's liking it alot for Drag racing but again the 2.6 with the lower rpm ratings it not desinged for low gears and hi speed at the same time. Yeah the 4:625's will get you there in a hurry with neck snaping torque but at the end of the quarter you will be redlining 5th gear at 6000 not good for an engine.
Later
Oscar
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