Converting auto too 4spd

[Murphy]

Excellant eye Darren! Your exactly correct, its a Saginaw.

[V8Freak]

I was told by the mechanic in out building that rebuilt it that it is a m21 where would the serial number be?

[V8Freak]

I found a few numbers I'll post them at lunch maybe someone can help figure them out I'll try also

[Murphy]

http://www.firstgenerationmontecarlo.com...6317&page=1

This link is to a previous post I had started when I bought my Muncie M20, scroll down to the pics I show of the tranny..

[V8Freak]

Ok so trans number is 3925661

Tail stock is 3978764

 

Casting: 3925661 Years: 1970 - 1974 Ratios: M20 2.52 1st , M21 2.20 1st, M22 2.20 1st

[V8Freak]

Here's the link

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

[V8Freak]

is it possible a tailstock from a Saginaw could be installed on a Muncie trans?

[V8Freak]

http://www.myss396.com/ChevelleInfo/Transmissions/Muncies.html

 

my god this is confusing lol

 

numbers on this site also tell me that my tranny and tailstock are in fact a 1970-74 Muncie but going by holes in tail stock it visually looks like a Saginaw this is stressful lol

[V8Freak]

date code is p4m10a

so according too the chart

its a 1970-74 Muncie

date code indicates it was built august 10th and that it is a M20

 

this is a real head scratcher id say

[V8Freak]

Just learnt something else, the guy I bought it from said its a 71 the older muncies had the by pattern your talking about and that was too be able too move the shifter forward or back newer muncies such as mine are only the 3 holes like a Saginaw

 

Well I learnt a lot this morning

My dads gonna flip I got two cars I'm working on but couldn't stop thinking about this problem lol

[V8Freak]

Saginaws are also cast muncies are aluminum

[MCfan]

Ok so trans number is 3925661

Tail stock is 3978764

 

Casting: 3925661 Years: 1970 - 1974 Ratios: M20 2.52 1st , M21 2.20 1st, M22 2.20 1st

 

[/quote

 

Okay, so you have a Muncie M20 with a tail housing that looks like a Saginaw ...

 

Your main case number is the same as mine, but the tail housing number is different (mine is 3857584 = 1966 - 1970 Passenger side speedometer, 27 spline output; yours is 3978764 = 1970 - 1974 passenger side speedometer, 32 spline output) which could explain the difference in mounting bosses.

 

Looks like we have come full circle back to suspecting that your shifter is incompatible with the standard hump. It would seem that any '71 Monte 4-speed would also have that main case/tail housing combo so there should at least be a factory Muncie shifter that was compatible with the standard transmission hump and console opening. Which shifter was mounted to your transmission when you discovered the interference and took those photos?

 

BTW, my sources indicate that Saginaws had the Reverse gear in the main case while Muncies had them in the tail housing so I doubt those tail housings are interchangeable. However, it might be possible to interchange the two different Muncie tail housings since they were both mated to the same main case in production. But, since the output shafts had different spline counts, there may be other internal differences as well. The solution still seems to lie in the shifter rather than the transmission or tail housing used.

[V8Freak]

Ok so trans number is 3925661

Tail stock is 3978764

 

Casting: 3925661 Years: 1970 - 1974 Ratios: M20 2.52 1st , M21 2.20 1st, M22 2.20 1st

 

[/quote

 

Okay, so you have a Muncie M20 with a tail housing that looks like a Saginaw ...

 

Your main case number is the same as mine, but the tail housing number is different (mine is 3857584 = 1966 - 1970 Passenger side speedometer, 27 spline output; yours is 3978764 = 1970 - 1974 passenger side speedometer, 32 spline output) which could explain the difference in mounting bosses.

 

Looks like we have come full circle back to suspecting that your shifter is incompatible with the standard hump. It would seem that any '71 Monte 4-speed would also have that main case/tail housing combo so there should at least be a factory Muncie shifter that was compatible with the standard transmission hump and console opening. Which shifter was mounted to your transmission when you discovered the interference and took those photos?

 

BTW, my sources indicate that Saginaws had the Reverse gear in the main case while Muncies had them in the tail housing so I doubt those tail housings are interchangeable. However, it might be possible to interchange the two different Muncie tail housings since they were both mated to the same main case in production. But, since the output shafts had different spline counts, there may be other internal differences as well. The solution still seems to lie in the shifter rather than the transmission or tail housing used.

 

 

Well the shifter in the car is hurst comp plus 2 numbers on the shifter are 3216274 and 3306126 don't know if it's the same number or 2 different numbers there was a small space between them

 

The one Sam says will work is also a hurst comp plus part # 3918014

[Sam (Bones)]

they did use some saginaw's or borg warners in the base 350 2 barrel models

 

and still used the muncie shifter that bolted to the crossmember

[LS5]

Sam, I didnt think you could use a Muncie shifter set up on a Saginaw as the reverse is in the Main case on a saginaw and the M20 is in the Tail ? The Rods are not interchangable as I must have spent $1000 just on rods and shifters for the Velle that were miss sold on ebay as Muncie when they were saginaw and would not work. I spoke with Brian at Team Muncie and he sold me the correct set up and rods but it wasnt until he told me saginaw stuff wont work on a M21 and the muncie wont work on a Saginaw hence the names, if they were universal back in 69/70 no one would buy either one they would only buy one and go with the universal set up but there wasnt one……….man I just confused the crap out of myself with all that….did you make any sense of that Sam..?? hahahaha…. all those pictures you sent me straightend the whole thing out. muncie is muncie and sag is sag and nothing else switches or am I missing something here…….? yes to the crossmember and muncies tieing in but not off a Saginaw Tail….. The saginaws in the monte's were the 3 in the tree cars were they not ….I dont think I have seen or heard of a Saginaw in a 2barrel 4spd car ????? it just doesnt sound right and man what a gutless 4spd that would be….a 2 barrel……

what am I missing here let me go get more meds too…………

I would hate to see Matt spend all this money and not get what he is after which I think is the full factory look on the inside buckets and console and shifter wise but the rest a resto look….?? is That right Matt ? if so the set up you are struggling with wont give you that……. in my opinion……. what you say Sam/Dennis…..

borg and warner we wont even go there as they are only good for churning ice cream…..stupid tranny's……..

Darren.

[Sam (Bones)]

I put an engine in a '70, 4 speed, but I think it was a borg/warner, and it was ALL stock, and a muncie shifter

[LS5]

ah yes, the Borg/warner has the same stock holes and same alignment as the muncie so you could do that……. that would have been a fancy Monte Ice cream maker.

Darren.

[V8Freak]

I am going for a stock look I like the idea of the buckets and console, what I do t get is I have a m20 from 71 so it should work some how

[V8Freak]

I guess the only option is getting a 4spd crossmember and getting the proper set up, its definitely money I wasn't planning on spending that's forsure

[Sam (Bones)]

you should still be able to use the hurst shifter

[V8Freak]

Leo wants me too call him, he' gas like 5 or so it looks like he's restoring currently 2 are 4sod conversion so I'll give him a buzz see what he has too say. Said it's too much too explain over email. That gear shifter would be the best solution for me.

[Murphy]

Just picked up my M20 from being rebuilt and Hurst shifter mounted.

Asked Ed, Muncie guy, about your situation and if a Saginaw tail can be mounted on Muncie main case and he said no way but if it did, nothing would line up inside......I then explained the issue of your shifter sticking way up high and he said common problem! Wrong mounting plate, the plate between the shifter mechanism and the tranny. He said people used the wrong ones or made something goofy. Saginaw mounting plate used on a Muncie tranny, Hurst mounting plate used with a Muncie shifter, etc, etc...

Ol' ED has been rebuilding Muncie's and Saginaws since the mid 60's (according to him) He's quite the old hotrodder.

[MCfan]

Lookin' real good, Murray! When are you going to make the swap? Bet you can hardly wait for the fun to start!

 

There are several different Hurst shifter mounting plates offered by Summit, but I couldn't find the details that explained which went with the various manual transmissions. Surely, someone in Summit's Tech Support can give some guidance if Matt has the wrong one for his current application.

[Sam (Bones)]

Murphy,

 

do yourself a favor and put nuts on those shifter handle mounting bolts after it's installed, that way you'll know it won't come loose

[Murphy]

Good point Sam, will do! The process will start this weekend or next for sure, just waiting on a few parts from Leo but I just as well get started on removing all the old stuff...........