Gear ratio question
#1
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Car: 87 camaro
Engine: 357 swap
Transmission: t5
Axle/Gears: 3.42
Gear ratio question
I know theres a simple formula to figure out the gear ratio and I cannot seem to figure it out. With one full rotation of the tire, I get approx. 1 3/4 turn of the driveshaft.
#2
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Car: 86 Trans Am, 92 Firebird
Engine: 408 sbc, 3.1L of raw power
Transmission: TKO600, T5
Axle/Gears: Moser 9", 3:70 trutac, 3:23 torsion
Re: Gear ratio question
its a bit more precise if you rotate the tire 5 or 10 times and count the driveshaft. divide the two. exp. 5 spins of the driveshaft divided by 2 spins of the tire is a 2.5 ratio
you need to spin wheel more, from what you give you come up with a 1.75:1 ratio, which is far from, what it is.
keep on spinning
you need to spin wheel more, from what you give you come up with a 1.75:1 ratio, which is far from, what it is.
keep on spinning
#3
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Car: 87 camaro
Engine: 357 swap
Transmission: t5
Axle/Gears: 3.42
Re: Gear ratio question
Alright so I finally got to doing this. So with 5 full rotations of the wheels I only got 8 and 3/4 rotation of the driveshaft... I am very un-happy with my current situation.
Somethings not right. But I counted correctly I am sure of it
Somethings not right. But I counted correctly I am sure of it
#4
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Car: 87 camaro
Engine: 357 swap
Transmission: t5
Axle/Gears: 3.42
Re: Gear ratio question
Any thoughts? Another thing...
I know the gear is poor because at 75 mph i am only at 2,500 rpms
I know the gear is poor because at 75 mph i am only at 2,500 rpms
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Car: 82 Z28
Engine: TT LS
Transmission: 4L80E
Axle/Gears: S60 3.54's
Re: Gear ratio question
I've done it 2 ways. For posi rears, just one rotation of the tires should give 2.5-3.5 rotations of the driveshaft; meaning the gear ratio is 2.55:1 up to 3.42:1. It's the same for a non-posi axle, but only let one tire rotate, and make it go 2 rotations.
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My guess is that you have a 3.42:1 because that 1.75 is far too close to being half your gear ratio.
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My guess is that you have a 3.42:1 because that 1.75 is far too close to being half your gear ratio.
Last edited by fast82z; 07-27-2008 at 04:51 PM. Reason: Automerged Doublepost
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#8
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Car: 86 Trans Am, 92 Firebird
Engine: 408 sbc, 3.1L of raw power
Transmission: TKO600, T5
Axle/Gears: Moser 9", 3:70 trutac, 3:23 torsion
Re: Gear ratio question
its time you just pull the cover off and count teeth, its not working for you any other way, and im sure the gear oil is in need of changing anyway.
#9
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Car: 87 camaro
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Axle/Gears: 3.42
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