Thread: Muncie 4 Speed

Tweet

I found one of these from a friend and I am wanting to get some info on these transmissions. I don't know anything about them. It came off of a 63 Vette I think it was (maybe 66, I have to ask again). He said it has the Z bar and bellhousing, etc. It's a aluminum casing and close shift ratio (that isn't the term I do not thing but you guys probably know) he said. Like I said, I dont know a think about them. Anyways, are these things any good? Pros and cons? I plan to hook it up to the 327 into my 54 Chevy HT instead of a 350 tranny. I figured that since all my other vehicles are automatics then I need a manual to have some fun in. The reason he is selling it is because he bought a 5 speed tranny for the car and no longer needs it.
I'd appreciate any info on this guys!

A Muncie in good shape is an excellent transmission. They were standard issue in the GTOs, Chevelles, 442s, Camaros, Firebirds, etc., through the muscle car era - even those with mega-horspower.

I had one in my '68 GTO. It had the 350HP 400 motor, which I rebuilt with way too much cam and gears to drive on the street - which didn't stop me, of course! I ran high 11's at Cornhusker Raceway outside Omaha. The car had 4.10 gears and 10" wrinklewalls when I took it out for the Wednesday bracket races. Launched at 6,000. Power shifted at 6500 without lifting the gas pedal. Nothing ever broke, and I only had to rebuild it once when it got a little noisy. Replaced the synchros and bearings and buttoned it back up.

The wide ratio had wider spacing betweent the gears. Low in an M-20 was 2.52 (or 2.56). The low in an M-21 was 2.20.

http://www.5speeds.com/muncie.htm

I prefer the wide ratio box, but the M-21 should work OK. Just a little less grunt in low gear. What rear end ratio are you using?

Look here for more info:

http://www.5speeds.com/muncie2.htm

Great site, thanks Henry! Do you think it's a bad idea to put this in my 54 HT then? I may just buy it for the hell of it to have around just in case (that's only if I can't use it on the 54.

Oh and as for gear ratio, I have a 57 Chevy rear end with a 3.73 gear in it. I was going to use this but that is a little too much gear for highway use I think. I might look for a Ford 9"
What do you recommend for cruising and some highway? I don't want it screaming at 3,500 RPM's down the freeway like my 66 F100 does, it's annoying if you know what I mean.

No, it's just not going to be any good, won't work, gas milage will be horrible, your arm will get tired from shifting, your left leg will cramp up, you won't get any dates, etc.

So what's this guys name and phone number?????????


In other words, if you DON'T buy it, let me know.


Don

PS: 3:73 is perfect for the street. Hiway may wind a little, but not real badly.

"Grab that Muncie", they dont make them anymore, and they are getting harder and more expensive to find. It wont hurt to have it sitting in the corner of your garage for future use. Think of it as an investment.

Shawn,

Heck, I'd use it. It's a classic old-school 4-speed.

I had 3.55s in my GTO with G70-14 redlines (26.8" diameter) before I went crazy with it. It turned about 3100 at 70 mph. With the 4:10's and Mickey N50's, it was a different story.

Calculate your RPMs at speed using the calculator below and see what you can live with. Figure out your tire diameter, then play around with rear-end ratios. Do what makes you comfortable. Maybe a 3.08.

http://www.csgnetwork.com/multirpmcalc.html

One good thing with the close-ratio Muncie and a 327 - once you get rolling, there's a smaller RPM drop between gears.

So looks like I should grab it and use it. I bought a tranny member kit from Chassis Engineering I think it was for 130 bucks. Looks like I need to sell it because first off, it's like 3 pieces of plate, second I don't see how it will work (might be the wrong part), 3rd, 130 bucks for that little thing that I could have plasma cutted out and drilled my own holes is way too much IMO. What will I have to do for my mount? Will it be moved forward I am guessing?
I put on the Fat Man MII Ultra Low front end kit and took out the original 54 chevy tranny cross member so I have nothing under there. I will ask him this week sometime how much he wants for it. He wont sell it (he's had it for a LONG time) so I dont need to be in a rush since I have first call to buy it.

Two words: Measure & fabricate . . .

My M-20 in my 55 had 3.55 gears which were perfect for the highway with my 26.4" tires. It also went through the 1/4 at 6200 in 3rd. Busted the 3.55's and went with a 3.70 I found. There not as plesent on the highway but still OK, the 3.70's should wind 3rd all the way out in the 1/4 havn't tried it yet.

Here is another interesting piece about muncies The early M22's up to 1970 came out with the 27 spline mainshaft and coarse 10 spline input shaft. They went up to the 26 spline input and 30 spline mainshaft in the big block Chevelles 197?. So practically all the early M22 1st generation Camaro's had the small mainshafts and coarse input shafts.

I will be running plain wide whites so they will not be tall tires at all. My 66 F100 has 3.70 gears in it with 75 series tires on 15 inch wheels and it revvs like hell down the freeway with a C4 tranny. I don't like the engine revving that high and long all the time.

I've seen some of the correct number M-22's, mainly the Vette ones, going for $1000.00 and up.... Might want to do some number checking and see what it came out of....

Originally Posted by FMXhellraiser

I will be running plain wide whites so they will not be tall tires at all. My 66 F100 has 3.70 gears in it with 75 series tires on 15 inch wheels and it revvs like hell down the freeway with a C4 tranny. I don't like the engine revving that high and long all the time.

It's probably that Blue Oval transmission slipping . . .

I run the M-20 in my 55 with 3:70 gears. Usaully run around 3500 rpm at 70 mph. Been doing it for 13 years now and it sounds great with the gear drive. Enjoy.