My drive gear is a brown 20 tooth and my driven gear is a red 37 tooth. This transmission is out of a '78 firebird, according to the guy I got it from. I think the engine was a 350 pontiac 2 barrel, but I'm not sure.
Speedometer Gear Questions...
- Thread starter MrSony
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Poking around online I see no 46 tooth gear, but 45's are available, but not the housing. The calculator says a 19 tooth drive gear and a 44 tooth driven gear will work for you and they are available as well as the housing for that range. I'm sure there are less expensive out there but this one is representative. http://rover.ebay.com/rover/1/711-5...0001&campid=5335822911&icep_item=132736676807 Just double check the calculator before anything.
I'm still not entirely sure how to use the calculator... do I punch in the number of teeth on the gears they showcase, the ones I have... or what?
I punch in the 19 you recommended for the drive gear, and it spits out 50 as the recommended driven gear... those don't exist.
I punch in 15, and it gives me 40, and 17 which gives me 45.
So would I be able to use either of those, the 15-40 OR the 17-45?
I punch in the 19 you recommended for the drive gear, and it spits out 50 as the recommended driven gear... those don't exist.
I punch in 15, and it gives me 40, and 17 which gives me 45.
So would I be able to use either of those, the 15-40 OR the 17-45?
So, since I have a 20 tooth drive gear, it says I would need a 53 tooth driven gear, those dont exist. So do I just go down the line until I find one that matches, like the 17-45 or the 15-40 that I mentioned previously? What's the difference between those two pairs? Do all these different ratios just accomplish the same thing, none are really all that much closer than the other? Or is there more to it?
http://rover.ebay.com/rover/1/711-5...0001&campid=5335822911&icep_item=132736676870
I think I'm going to go with these, 17-45 gears and the housing. Sounds about right to me.
I think I'm going to go with these, 17-45 gears and the housing. Sounds about right to me.
The calculator has one variable that I can't guess at and that is the speedo rpms per mile. Not knowing what yours is I used 1000 which it says older cars used. If you have a different factor then the ratios would change. What did you use? EDIT: I just looked at my own and there is no number on the speedo face. I am at a loss on that.
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We are not on the same page. When I pop a 17 tooth drive gear into the formula I get a 39 tooth driven gear. When I pop a 45 tooth driven gear in I get a 19 tooth drive gear. How do you get 17/45? I used 1000 rpm, 26.10" tire, 3:42 gears. Also I see only housings that go to a 43 tooth gear. Will a 45 fit? I don't know.
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