Quick question about gears:
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Race Director
Joined: Oct 2001
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From: Canton GA
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St. Jude Donor '03-'05-'06-'10-'11-'12
Quick question about gears:
I have a 1992 LT1 with the (awsome) ZF 6-speed transmission, but what gears do I have? I can't be sure what they are at the moment (previous owner may have changed them), how would I tell without pulling the cover and counting ( :U )??? Is there a RPM to speed calculator that I could use?
Le Mans Master
Joined: Aug 2000
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From: Bloomington IL
Re: Quick question about gears: (92Shawnster)
The console lid will have the codes for the original axle ratio. I'll leave it to other forum members to help with any other methods to determine rear axle ratio.
Burning Brakes
Joined: Sep 2000
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From: NewCastle IN. USA
Re: Quick question about gears: (92Shawnster)
there is a formula.
gear ratio= (rpm x tire dia) divided by (mph x 336)
however that will give you total gear ratio ( the OD in the transmission will affect it) so divide that number by the OD ratio (for a ZF 5th is .75 and 6th is .50 ).
the simplest way to do it is to jack the car up and turn the wheels one turn while counting the rotation of the drive shaft (mark them with tape).
example: if the drive shaft turns 3 and 1/2 turns for one turn of the wheels then it has roughly a 3.50 to 1 rear gear.
gear ratio= (rpm x tire dia) divided by (mph x 336)
however that will give you total gear ratio ( the OD in the transmission will affect it) so divide that number by the OD ratio (for a ZF 5th is .75 and 6th is .50 ).
the simplest way to do it is to jack the car up and turn the wheels one turn while counting the rotation of the drive shaft (mark them with tape).
example: if the drive shaft turns 3 and 1/2 turns for one turn of the wheels then it has roughly a 3.50 to 1 rear gear.
Thread Starter
Race Director
Joined: Oct 2001
Posts: 12,832
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From: Canton GA
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St. Jude Donor '03-'05-'06-'10-'11-'12
Re: Quick question about gears: (ol,RJ)
Excellent! Great formula. Thank you much! :seeya
Thread Starter
Race Director
Joined: Oct 2001
Posts: 12,832
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From: Canton GA
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St. Jude Donor '03-'05-'06-'10-'11-'12
Re: Quick question about gears: (92Shawnster)
Oh, RPO: GM3 (3.45). :D
What would the G92 "Performance Axle" be?
What would the G92 "Performance Axle" be?
