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What is the main difference between a Saginaw 4 speed trans and a muncie 4 speed I am starting to shop for a rear end transmission set up. I have a stock '54 235 and w/ the exception of some top end stuff I don't plan on making any other changes. I'm just starting to read and learn about all the choices. To be informed is to hopefully avoid common pitfalls. Thanx.

The Saginaw is a cast iron case transmission, while the Muncie is aluminum. Saginaws are a little newer, as the Muncie was used mainly back in the 60's and early 70's. Most of the Muncie transmissions are like old 216's they've been trashed and rebuilt several times. The drag racers went through Muncie transmissions like popcorn whrn the cars that ran them were active, so supplies are a little scarce. I'd reccomend the Saginaw, if a good-condition box can be located. The Chevy Vega ran the Saginaw, and several other, similar cars from Pontiac, etc.
Jerry

The main difference between the two types for use behind low HP engines is the gear ratios and price.Muncies had a 2.20 and 2.54 first gear,the Saginaw has 2.54,2.85,3.11 and 3.50 first gear ratios.Saginaws also cost a lot less.
Saginaws were used in non hi performance V-8's,Camaros,Firebirds,Chevelles,etc and Monzas,Sunbirds and the like.Saginaws 4 spd production was from around 1967 until the early 80's.

If you are going to swap to a transmission that requires an open driveline anyhow, why not think about a 5 speed? The fifth gear overdrive'll make it nice on the freeway and the borg-warner t-5 that came in s-10's and blazers basically bolts right up to your bellhousing. I just modified a t-5 to put in my '51 and it took me all of an hour to measure, cut, grind and drill. Basically all that you need is a $15.00 4" angle grinder from harbor freight, which comes with a grinding stone and cut off wheel. You measure the length of the pilot bushing portion of the input shaft on the original tranny and grind down the t-5 to match. I took off less than 1/2 an inch. Then on the input shaft housing (the sleeve around the input shaft infront of the tranny) you do the same thing. I cut off around 1" of that and it took 15 minutes including measuring and marking it and checking the measurements and marks. Then what's left to do is to drill out the lower mount holes in the t-5 'cause the holes are a little to small for the original bolts. I'm using the clutch plate that came with the t-5 and the pressure plate/throw out bearing/flywheel that I already had. Once you've got those parts taken care of you'll have to remove the transmission cross member (it bolted into my truck, so was easy to remove). Then measure the driveshaft length and get the one you've got shortened and balanced, if necessary. Don't forget to set the transmission output shaft angle and axel pinion angle. The shifter comes up to the cab about 6: back from the original so you'll have to deal with modifying the transmission cover somehow, I'm using a 3-spd cover and cutting a new hole. (about $40 from ChevyDuty). After that, if you want, you could weld the orinigal shifter from your truck onto the shifter from the t-5.
All in all, with the tools and parts in hand, maybe a saturday job. A benefit beyond the overdrive was less weight, a back up light switch from the tranny, better gas milage, easy to find parts for the t-5 (rebuild kits are $125 for everything!), etc...

The muncie trans is a lot stronger than the saginaw(junk)thats why all the hot rodders used them also why the factory used them behind all Hi horse power engines

Which cars came with the muncie. 5sp trans?

Nm51 Sounds like a winner. Thanx for the info. I can't wait to get started. It'd be nice to be able to drive @ a somewhat modest speed w/o worrying about overrevving every time I get her up to 60. By the way what about yer--er--I mean her rear end? What did ya plug the Borg into? Have good And Keep Surfing if ya got an ocean near by. Osidejack out.---------

nm51, is correct, i just did the t-5 swap this week and wish as always i had done it years ago. every thing seems to work better. i have a nova 2.73 rearend and most people said the ratio would not work but i am satisfied. btw it is mostly flat here. also you can go to www.mongosgarage.com and look at his project pages for the writeup on this swap. RON

When you think trannys also think rear ends cause they're connected. The rear end will limit your overall hiway speed even after you installed that pretty new 4 speed. Here are several sites already discussed on 'the bolt' about determining rear end ratios for the type and gear box you're about to buy. just plug in the boxes and hit the calculate button.
Also consider when you find &/or have built a T5, you may be able to have one built using camaro guts installed into an S-10, depending on your pocket book. Many of us love the T5's and after getting mine built I will not have to worry about pulling a used tranny out to rebuild it... ever. I'm using a 12 bolt 6 lug Chevy 1977 burb rear end w/ 3.43:1, w/ big brakes. Your choices w/ that mid 70's vintage truck rear ends are 3.08, 3.43, 3.73 in 6 lug. There are many other choices. Your choice will be determined by where you live (mts, flat driving roads, hauling, trailer usage, speed & acceleration, etc.)
Have fun
Gooday
jim

see: http://www.stovebolt.com/bboard/cgi-bin//ultimatebb.cgi?ubb=get_topic;f=2;t=009842

http://www.stovebolt.com/bboard/cgi...d=results&record=2453602-095913-JBXJ

That list of t-5 transmissions from Mongo's Garage is great. One question though. Which ones will bolt up to my Stovebolt, 235? Does the t-5 have to be from a GM? Nissan even used the t5!

This sounds GREAT but what about 292 options? Can the same be done for it? Thanks in advance.

Rance

PS: Osidejack, I hope this don't hijack your thread.

Rance, No problem thread on.---- Jack