Gear ratio calculator ???
Thread Starter
Racer
Joined: Aug 2003
Posts: 460
Likes: 15
From: Belgium /
Gear ratio calculator ???
Hi, I am looking for an easy to use and good gear ratio calculator, I know it saw one here some time ago but I can't find it anymore :confused:
I am planning on installing a 200R4 and would like to find out what the best rear end gear would be for me ...
Thanks
Stef
I am planning on installing a 200R4 and would like to find out what the best rear end gear would be for me ...
Thanks
Stef
Racer
Joined: Dec 2003
Posts: 257
Likes: 0
From: Livermore CA
Re: Gear ratio calculator ??? (stingraymax)
Here is one I've used before:
http://www.quiknet.com/~ke6vut/rpmcalc.html
Hope it helps you :cheers:
http://www.quiknet.com/~ke6vut/rpmcalc.html
Hope it helps you :cheers:
Le Mans Master
Joined: Apr 2000
Posts: 7,562
Likes: 9
From: B'Ville NY
Cruise-In III Veteran
St. Jude Donor '05
Race Director
Joined: Jan 2003
Posts: 15,175
Likes: 86
From: State of Confusion
Re: Gear ratio calculator ??? (stingraymax)
Write this down on a piece of paper, & keep it with your pocket calculator...
If you know the height (in inches) of your tire;
RPM x .9 (if non-locking converter or stick-shift) x .006 x 1/2 TH (tire height {in inches}) divided-by MPH = gear ratio needed to run THAT MPH at THAT RPM with THOSE size tires.
If you run an OD transmission, you must divide THAT # by the OD ratio (700R4 is .7; I'm not sure about the 200-4R).
In my '82 (before the gear-swap to 3.73:1), I'd turn 1500 RPM @ 60 MPH (verified) with 27" tires, a lock-up converter, & 2.87:1 gears.
Thus:
1500 (RPM) x .006 x 13.5" div/by 60 (MPH) div/by .7 (OD) = 2.892, or very close to the 2.87:1 gears in the car.
'Old-time' racers keep this formula handy...
If you know the height (in inches) of your tire;
RPM x .9 (if non-locking converter or stick-shift) x .006 x 1/2 TH (tire height {in inches}) divided-by MPH = gear ratio needed to run THAT MPH at THAT RPM with THOSE size tires.
If you run an OD transmission, you must divide THAT # by the OD ratio (700R4 is .7; I'm not sure about the 200-4R).
In my '82 (before the gear-swap to 3.73:1), I'd turn 1500 RPM @ 60 MPH (verified) with 27" tires, a lock-up converter, & 2.87:1 gears.
Thus:
1500 (RPM) x .006 x 13.5" div/by 60 (MPH) div/by .7 (OD) = 2.892, or very close to the 2.87:1 gears in the car.
'Old-time' racers keep this formula handy...
Le Mans Master
Joined: Aug 2003
Posts: 7,720
Likes: 12
From: Chattanooga TN
