[David Jones]

Originally Posted by ITSBACK

Wouldn't raising the back of the transmission make the angle greater as it is closer to the rear than the m20. I could be wrong but in my mind I see a shorter driveshaft and a higher transmission.

I ended up with 3 (approx 3/8" total) washers under both transmission mount bolts (crossmember) to get under 3 degrees down (up in front, down in back) which is where you want to be. I am now much closer to the trans tunnel and would have altered my opening initially had I known I'd needed to come up more.

[jonathonar89]

Originally Posted by ITSBACK

This thread is getting hijacked, lol.

Breaking news...overdrive cut gears for muncie transmissions

http://autogear.net/ag_archive/literature2.htm#

[GTOLou]

Originally Posted by ITSBACK

This thread is getting hijacked, lol.

Lol.... no kidding. I am one of the ones hijacking!

Problem is...you can buy a TKO 500/600 for 2500 bucks or so - but the "perfect fit" business might cost another 1000!! Upping to a 5speed seems more expensive than I originally thought.

[David Jones]

Originally Posted by GTOLou

Lol.... no kidding. I am one of the ones hijacking!

Problem is...you can buy a TKO 500/600 for 2500 bucks or so - but the "perfect fit" business might cost another 1000!! Upping to a 5speed seems more expensive than I originally thought.

Try starting the swap with a Turbo 400.........

[GOAT WHORE]

Originally Posted by jonathonar89

Breaking news...overdrive cut gears for muncie transmissions

http://autogear.net/ag_archive/literature2.htm#

Yaaahhhh, not quit the same.

[Ben M.]

Originally Posted by GOAT WHORE

Yaaahhhh, not quit the same.

Not to mention I don't know of a single person who has used it. Last update on that site for that setup was like 3-4 years ago...

[GOAT WHORE]

Originally Posted by Ben M.

Not to mention I don't know of a single person who has used it. Last update on that site for that setup was like 3-4 years ago...

Said it was for a 4.11 rear gear and would produce a final drive equal to a 3.55 in 4th. Not an overdrive at all.

[KJL]

I'm running a M21Y gear set in my 70 GTO. The OD is .86:1 and make my 3.90 rear look like a 3.36 in 4th (OD). Not a real big reduction but enough to reduce 400 rpm at 60 mph. The only thing you have to get used to is the large ratio change from 2nd to 3rd (which is the old 4th gear) and the small ratio change from 3rd to 4th (old 3rd gear now an overdrive). If I had to do it over again, I would have kept the M22 and change the rear to a 3.55 or changed the Muncie to a M20 gear set and find a 3.31 or 3.23 rear. I believe Tom S had one in his Trans Am and if I recall correctly he liked it.

[jonathonar89]

Originally Posted by KJL

I'm running a M21Y gear set in my 70 GTO. The OD is .86:1 and make my 3.90 rear look like a 3.36 in 4th (OD). Not a real big reduction but enough to reduce 400 rpm at 60 mph. The only thing you have to get used to is the large ratio change from 2nd to 3rd (which is the old 4th gear) and the small ratio change from 3rd to 4th (old 3rd gear now an overdrive). If I had to do it over again, I would have kept the M22 and change the rear to a 3.55 or changed the Muncie to a M20 gear set and find a 3.31 or 3.23 rear. I believe Tom S had one in his Trans Am and if I recall correctly he liked it.

I admire 5 and 6 speed transmissions but I'm also going to be trying out a weird 4 speed setup. 2.64 T10 trans with a 2.73 10 bolt rear in my firebird. I also plan on changing to a shorter 275/40 17 (25.7" tall) tires so that's a changing factor in my equation.

[Overkillphil]

Originally Posted by GOAT WHORE

Yaaahhhh, not quit the same.

X2! That thing would feel similar to an SROD trans.

[FirebirdHank]

[QUOTE=jonathonar89;5121577]I admire 5 and 6 speed transmissions but I'm also going to be trying out a weird 4 speed setup. 2.64 T10 trans with a 2.73 10 bolt rear in my firebird. I also plan on changing to a shorter 275/40 17 (25.7" tall) tires so that's a changing factor in my equation.

[/QUOTE


When I first switched from auto to manual I had a Saginaw 4 speed with a 3.11 low gear and a 2.56 rear end. It actually drove out pretty well. Both the tranny and rear end had issues however so that combo did not last long.

[Jim Doran]

Originally Posted by David Jones

I ended up with 3 (approx 3/8" total) washers under both transmission mount bolts (crossmember) to get under 3 degrees down (up in front, down in back) which is where you want to be. I am now much closer to the trans tunnel and would have altered my opening initially had I known I'd needed to come up more.

David, curious but isn't there a specific distance to move the crossmember back, coupled with the transmission mount, should take the guesswork out... or maybe not.

Was there variability on how far back you moved your crossmember or did you move it the exact proper amount and yet it still requires some shimming to get proper geometry ?

[David Jones]

Originally Posted by Jim Doran

David, curious but isn't there a specific distance to move the crossmember back, coupled with the transmission mount, should take the guesswork out... or maybe not.

Was there variability on how far back you moved your crossmember or did you move it the exact proper amount and yet it still requires some shimming to get proper geometry ?

I was able to reuse one hole on the crossmember on either side. I think that is fairly normal. I don't remember Keisler having a measurement in their instructions? They had guidance. As I sit here I don't remember what it was.

The problem angle is in the transmission output shafts relation to the pinion angle. As my trans sat on the mount and it sat on the crossmember, the trans output shaft was 4.5ish degrees (down at the rear...from
memory here...) and needed to be less than 3.

[old66tiger]

I see on the Pro-touring forum that the driveshaft shop offers a cv style shaft that takes the u joint angle problem out of the equation. Pricey solution but it is pretty cool.

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[chuckies76ta]

Originally Posted by old66tiger

I see on the Pro-touring forum that the driveshaft shop offers a cv style shaft that takes the u joint angle problem out of the equation. Pricey solution but it is pretty cool.

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Can you post a link please.

Thanks

[old66tiger]

http://www.pro-touring.com/threads/4...=cv+driveshaft. Go to page 28

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[old66tiger]

The carbon fiber deal was a bit more expensive, but I think this guy is willing to spend the extra. An aluminum version is about $900 if I recall correctly. Pricey, but if it solves the problem, it's worth it.

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[chuckies76ta]

Thank you

Charles