All GM gears the same?
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From: kennett square,pa,us
All GM gears the same?
There has been quite a bit of discussion about gears on the Forum lately, which sparked my curiously about weather the gears in the Corvette are the same as in Camaros,Chevelles, etc. Did GM make 4:10, 3:73, etc, gears for other cars? If Gm made 3:90 gears for the Vette, wonder why they never offered them as an option?
Thanks.
Thanks.
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From: Forked River NJ
Re: All GM gears the same? (bud snyder)
The Vette gears are different from 10 and 12 bolt Gm rear ends. I think the 3.90 is a Richmond only gear. The Vette gear is actually a 3.70 where the 10 and 12 bolt gears are 3.73. They are definitly different.
Thread Starter
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From: kennett square,pa,us
Re: All GM gears the same? (Gordonm)
Gordonm,
Thanks for the info. I have a part number for 3:90 gears from GM in my Chevy Power book dated 1977. 3970551 (39/10T) I did notice that all the other ratios start 396 except for the 3.30 & 5.14 gears.
Thanks,
Bud
Thanks for the info. I have a part number for 3:90 gears from GM in my Chevy Power book dated 1977. 3970551 (39/10T) I did notice that all the other ratios start 396 except for the 3.30 & 5.14 gears.
Thanks,
Bud
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From: Forked River NJ
Re: All GM gears the same? (bud snyder)
My parts book lists the 3.90 also. I don't know why it was not offered but probably so close to the 4.11 gear. Never heard of the 3.30. Have seen a 5.14 now that is a wicked gear.
Just noticed tour from Kennet Square. Do you ever attend any local events over in S Jersey. I may have seen you if you have
[Modified by Gordonm, 1:54 PM 11/3/2001]
Just noticed tour from Kennet Square. Do you ever attend any local events over in S Jersey. I may have seen you if you have
[Modified by Gordonm, 1:54 PM 11/3/2001]
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From: WI
Re: All GM gears the same? (Gordonm)
GordonM,
I would think the 3.90 was offered "over the counter" as were many Corvette race pieces (Kustom BB headers, fender flares,J-56 brake parts, etc.) i also think there was a 4.56 available. The 3.30 is a 3.36. There is a way to use the 12 bolt parts in a Vette rear, but i`m not sure if its the R&P and / or the 12 bolt posi unit, i think there is some machine work needed.
...redvetracr
I would think the 3.90 was offered "over the counter" as were many Corvette race pieces (Kustom BB headers, fender flares,J-56 brake parts, etc.) i also think there was a 4.56 available. The 3.30 is a 3.36. There is a way to use the 12 bolt parts in a Vette rear, but i`m not sure if its the R&P and / or the 12 bolt posi unit, i think there is some machine work needed.
...redvetracr
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From: Forked River NJ
Re: All GM gears the same? (redvetracr)
Ok on the 3.36 gear that makes sense. So does the over the counter gears. I have seen and read on Toms Diff. site about the 12 bolt rear in the Vettes. Quite a rear indeed. I'm not making nearly tha tkind of power to require this. My check book is not that big.
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From: kennett square,pa,us
Re: All GM gears the same? (Gordonm)
Gordon,
Sorry i have never been to any fuctions in South Jersey. I have a good freind that lives near Atco and grudge races his Super B there. I have talked about getting together with him and seeing what the new engine mods can do.
It is a shame that they never used 3.90 gears as a new car option.
I have Richmond's in my car and they are great. Probally the best single mod I ever did to the car.
I can't imagine 5.14 gears in any car, it would have to be an auto, who could shift that fast!
Bud
Sorry i have never been to any fuctions in South Jersey. I have a good freind that lives near Atco and grudge races his Super B there. I have talked about getting together with him and seeing what the new engine mods can do.
It is a shame that they never used 3.90 gears as a new car option.
I have Richmond's in my car and they are great. Probally the best single mod I ever did to the car.
I can't imagine 5.14 gears in any car, it would have to be an auto, who could shift that fast!
Bud
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Joined: Dec 1999
Posts: 19,610
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From: Forked River NJ
Re: All GM gears the same? (bud snyder)
A great local show at Atco is in the spring. It is a fun and run event. Last year I got in 17 runs and that was with a 30 minute pit stop for linkage problems. It is a show put on by a local club and usually draws about 50 to 70 cars. It is Vettes only so you can run as much as you like. I have made the last 5 events there and have had a blast at all of them.
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