When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I bought a basket case car, and I need your knowledge about G/box.
This box looks like a M22 from the casting numbers, but I have never seen one in real life before .
I've looked at a few pictures on the InterWeb on how to identify a M20/21 from a M22 and...I have to say...based on the pitch of the teeth, you may have a M22 on your hands.
I will offer that, when driven, the first gear of a M22 has a distinctive "whine" created by its extremely heavy duty straight-cut first gears.
I will also offer that there are FAR fewer M22 transmissions in existence than evidenced by all the bench racers that say they have a "Muncie Rock Crusher" in their car. The M22 transmission is not very common.
But...like I said...the width of the top of the gear teeth is very distinctive. Looks like the bad boy to me, if pictures are to be trusted.
Ratios appears to be: 2.20 / 1.64 / 1.28
I cannot find information, not looking at the right place maybe, about Autodyne. This box was on a to be historic race car who after 8 to 9 years, was never completed . So paper work and memories faded away.
Any comments appreciated. Thanks in advance.
Thierry
I took the pics myself just few hours ago. So you can trust them
Looks like that a year on the tail housing appears to be 1972, maybe.
As I have no stamping on the main casing shows that box is not coming from another car..?
Last edited by OZGreen69; Mar 6, 2016 at 01:48 AM.
Reason: Spelling, Dohhh!
I don't want to sell it, because this is one of the best gearbox that I can run in my class. I must have the original casing (casting numbers) of my car year. So short of building a M something with AGE gears inside this one was cheap enough and new, to make me smile!
Thanks for the tip about the other boxes.
Autodyne appears to be related with Medatronic. Could those guys built it, I should contact them. A drain plug is there, maybe not " factory " installed.
Anyway, looks like a M22,smell like a M22, taste like a M22. Must be a M22 !!
Well...there's little question there are M22 guts in there. Not to take anything away from the transmission, but that doesn't necessarily mean it started life as an M22. The casing could be from another trans and it was rebuilt with M22 guts.
It's awesome either way, don't get me wrong. I've just stopped being surprised by what is found in some of these old parts. People have done lots of odd things to these cars for lots of odd reasons.
Keith, I totally agree with you. I understand by talking with the guy who was building this car for the then owner, that the box was ordered from Autodyne circa 2002. So, I think Autodyne assembled that box from separate components to make a "M22" . As no stampings are present on the main case " shows " that it was a new one, looks like to me anyway.
Like I said...probably wouldn't make much difference to me. Looks minty fresh inside.
When you get to "stupid" horsepower levels, I believe the casing itself is the weak point, not the gears inside. I'd do a M22 gearset just to hear the gear whine and say I have a "Rock Crusher".
I haven't looked, but I believe there are folks that have created a heavier duty case within which all this stuff can go.
Of course, if you start getting too silly about it, a TKO500 5-speed becomes a very real option.
Looks awesome, though. I LOVE finding better stuff than I expected inside of things.
From: Las Vegas - Just stop perpetuating myths please.
Value wise it makes for a strong Muncie - that is if the gears are still good. It needs a total inspection before use. But no way collectable value. The earliest M22s were somewhat conversion like but I believe had some unique machining. U should post this on the C2 forum for more accurate help.
BTW I have basterized 1965 Muncie case to but my gears look like the wider M20/21 headset - and missing a few teeth to.:-)
Muncies don't have vents from GM on the main case or tailhousing, if it is a vent, there is the possibility under hard braking it will leak lube out the front drive gear unless someone has put a seal system on the input shaft. Factory, Muncies are vented through the input shaft and will start to leak when the tailhousing seal starts to fail.
I'm pretty sure Autogear now sells a sealed front input shaft set up but, I've never run one.
Unit #1257 M22 transmission was built in Febuary of 1989 for a road race client based in NY. Looks like new internally considering when it was built. It should have a roller first gear. I just completed units #4071 and #4072 to give you perspective. Built with new upper GM M22 gears at the time except I was usually using Perfection ( ZOOM ) M22 countergears because they made them out of 9310 alloy. The fittings you see on the case were for a cooler pump system and are not a vent. This is pre-Autogear anything. Autogear didn't get into making parts for Muncies until 2002 - 2003. So you had to work and modify GM castings and use what you could obtain. Factory gears by the late 1980's were already starting to get problematic finding them and cost way more than the stuff you can get today.
Thank you very much Paul. Those information are much appreciated and I dare to say that I am excited ( Wife's rolling her eyes now !).
Regarding the mention by Solid LT1 about the vent. Could it be possible or necessary, to improve it ? I mean, by a front seal and a tail housing breather ?
Muncie M22 ??
( Wife's rolling her eyes now !).