The Stovebolt Site Forums The Shop Area The HiPo Shop Muncie Tranny

Hey All,
Need some advise ..I been lookin at E-Bay an such at prices.
Heres the POOP.
Dude I work with has a 1970 Muncie 4 speed (rockcrusher) out of a 70 Chevelle that was hooked to a 396 that he totaled many yrs ago.
I tried to purchase the combo for yrs. now he wants to sell me the trans an keep the motor ..
ANY suggestions on what to OFFER???,,trans has roughly 80 thousand miles on it.
Thanks,
Tim

Those M-20 rock crushers usually go for around $800 to $1200. I've seen some for around $1500. that have been rebuilt.

Correction - the M-22 is the rock crusher Muncie and they whine real nice. What a sound. I think 1974 was the last year they were made. There is a company out there now making them again. They go for $1675.

You should verify that it is truly an M22 first. i'm suspect that it isn't, especially being behind a 396. More likely, it's an M20/21 or even possibly a Saginaw. The M22s saw more use in 427/454 powered cars, and also in the hotter small block Corvettes and Camaros.

Here is a good link so you could make sure it is a real M-22
http://www.5speeds.com/muncie2.htm

Thanks for the link Slickt

OK,
Ive looked at the #'s ..the site Slick gave me has a ton of info Im pretty sure this Trans is a M-20.any help will be great, heres the #'s I found on the trans.
Casting # 3925661
POC23
3088336
10A148372
Tailshaft # 3857584GM
Input shaft is 10 spline with 2 grooves machined in it.
26 splines on the out-put shaft
The owner let me open the case to ispect it and everything looks to be in great shape ..no chips or excesive wear on the gears,end play is tight all over..looks pretty darn good.
So I offered $300 he accepted so now it is mine.
Good Purchase or NOT ?
Thanks,
Tim

Pretty good deal- - - -not a bargain, but you didn't overpay. I believe the 2-groove input shaft means you've got the wide-ratio box with the 1.88:1 2nd gear. Don't quote me on that, though- - - -it's been 35 years since I ran one in the dirt tracker!
Jerry

If it came with the Hurst shifter you got a great deal.

did you look at the gears or the teeth where the scycro. rings slide together? that is the important part they can be burred or chipped. i spent many hours stoning those teeth to get them to shift right. to get it to shift good you have to squeese the shifting forks so there is min. clearance on the rings. i built many slick shifting muncie transminisions.

if it has 2 groves you have a wide ratio with a 2.56 first gear. if it has 1 grove it is a close ratio with a 2.20 first gear.

Thanks for the replies Gents!
Well no shifter with it, buds Uncle beat me to that!...lol
did get the bell housing,throwout bearing arm and ball.
No chips or burrs I can see on the gears or syncro's.
So Should be a decent addition to a project im starting soon.
Thanks again!
Tim

What are your plans for this truck? I would consider a Muncie in a hotrod, not in anything you're going to use to haul or tow something. By today's standards they are very limited. The gear spread is too close for a nice torquey big inch engine, too close for a 6 cyl for the same reason, and not enough gears if you drive it on the highway. They can't be beat for rowing gears, but the ratios are lousy these days. If you're going to drive it on the highway at all figure where you'd be comfortable and gear the rear appropriatly, then expect to slip the clutch a bit from dead stops.

Devin

Devin,
Thanks for the tip, this tranny isnt goin in a truck, ya see Im comin down the home stretch on my bolt as far as it is 99% done.
My new project is a 1975 Chevy Laguna Ive been gatherin parts for years to build (my first car at 16 was Guna)..My youngest is now 14 and is harpin on me BAD to get started on the Guna we picked up a few yrs. ago, currently we have a nice solid car with a well built 350 & 411 posi but it currently has a 350 turbo and we want a 4 speed.
Sorry if I missled anyone.
Tim