My2nd 69 442

Can any of the Transmission experts here tell me what speedo gear that I should have in my 69 442 with a stock 4 speed with a 3.23 rear end and stock 14 inch wheels with P225R70 14 tires?
Thanks
Jerry

svnt442

Well from what I could find the 225/70/14 equates to an G78/14 tire.
The service manual says that you would need a 17 tooth driven gear with a .866 adapter.
I think if you use a 19 tooth driven gear it should be close enough. It will still read a tad fast, but shouldn't be way off. You might even want to try a 20 tooth.

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My2nd 69 442

Thanks Randy
The chart you posted is very helpful
I found an online site "Vintage tire size conversion" that list my P225 70R 14 as same as H78 tires and thus requires a 19 tooth driven gear.
Next time I put my 442 on my lift, I'm gonna check and see that I have the proper gear installed and attempt to see if the Drive gear is at least the right color if possible

Inline

Sorry for high-jacking the thread. Wouldnt otherwise made a thread to just ask a simple question like this, but as the situation arrives..

Ffrom old charts ive found and done some calculations,
with 255/60/15 rears and 3.42:1 axle ratio, am i right that i should use as drive gear one of the following: pink, black or red, and corresponding driven teeth on same order forming pairs should be brown, blue and purple?
And really stupid question after all of this, which way it goes, having over-ratio ( like having calculated to need 20.38 driven gear, and picking one with 20) results in speedo showing a tad too much=? And vice versa, having under-ratio results for showing too small reading...?

Thanks.

My2nd 69 442

Inline
I think if my speedo was just a "tad to much" that I would be happy with it and you would probably see fewer cop lights in the rear view. My speedo is about 12 MPH low above 35-40 MPH. Mr John Law didnt like that very much.
Speed o said 55 cop said 67. At least he was cool. Talked about the car for a few minutes and away I went with a warning

Phoenix8990

Well mine reads 80 when I'm doing 60, I'll never get a speeding ticket at that rate. I've changed the gear to what I was told was correct for a TH400 but I'll have to check the CSM.
Steve