| FAQ |
| Members List |
| Social Groups |
| Calendar |
| Search |
| Today's Posts |
|
#1
08-06-2021, 10:47 AM
|
|||
|
|||
TH400 speedometer gears
I have a 1969 TH400 with P235/60/R15 tires, 3:55 gear. What speedo gears do I need? Anything else to know on installation?
|
|
#2
08-06-2021, 11:56 AM
|
|||
|
|||
|
How to Change TH400 Speedometer Gears
https://itstillruns.com/change-th400...s-7669072.html There are on line videos as well. Regarding gear codes... https://transmissioncenter.net/shop/...r-driven-gear/ A P235/60/R15 tire should be around 26.1 inches in diameter. .
__________________
'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 ) Old information here: http://www.hotrod.com/articles/0712p...tiac-trans-am/ Sponsor of the world's fastest Pontiac powered Ford Fairmont (engine) 5.14 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension https://www.youtube.com/watch?v=qDoJnIP3HgE |
|
#3
08-06-2021, 01:30 PM
|
|||
|
|||
|
need to know your drive gear. (gear on the rear transmission shaft.) if you pull the driven gear housing, you may be able to see the color of the gear. not all of them are plastic though.
you're going to want a drive gear of around 15-16. you'll also need a Driven housing that supports the larger driven gears. 40-45 i believe. i'm calculating 16/44 or 15/41 as the combos you'll want.
__________________
1979 Firebird Trans Am 301/4spd (Now 428) 1977 Firebird Formula 400/Auto 2007 Grand Prix GXP 5.3L |
|
#4
08-06-2021, 06:59 PM
|
||||
|
||||
|
Ideal targets, not all combinations are viable or available.
|
| Reply |
|
|
The PY Online Forums is the largest online gathering of Pontiac enthusiasts anywhere in the world. Founded in 1991, it was also the first online forum for people to gather and talk about their Pontiacs. Since then, it has become the mecca of Pontiac technical data and knowledge that no other place can surpass.
Linear Mode
