Transmutation gears calculation
Thread Starter
Racer
Joined: Jul 2001
Posts: 483
Likes: 3
From: d.d.o quebec
Transmutation gears calculation
I switch my TH350 to a 700R, the speedo is of. I have 255/60/15 tires with 3.55 gears. At 100 KPH the speedo reads 119 what gear should I have. I don't know what is in there now.
Le Mans Master
Joined: Dec 2007
Posts: 6,422
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From: McHenry Illinois
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
You need to know what [inner] speedo drive gear is fitted to the output shaft of the transmission. Knowing that, you can determine if you can correct your error with only a change to the speedo driven gear. Otherwise, you will have to change both gears.
The best time to select and install the speedo gears in an auto tranny is before you install it. You can use the speedo gears in the TH-400 unit to help determine the correct gears for the new tranny.
19 mph error at 100 mph (actual) is a 19% change. You will most likely need to change both the internal and external transmission speedo gears.
The best time to select and install the speedo gears in an auto tranny is before you install it. You can use the speedo gears in the TH-400 unit to help determine the correct gears for the new tranny.
19 mph error at 100 mph (actual) is a 19% change. You will most likely need to change both the internal and external transmission speedo gears.
