Transmission help choices/decisions

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CORPO

Buildin' it his way, one piece at a time...
Joined
Jul 11, 2008
Messages
2,636
Location
Chicago
Im going to be digging the frame out of storage soon and finishing the fab work on it which includes transmission cross member...

I currently have a aluminum power glide, but am really looking to go to a manual trans. I figure I should nail this down now so that the cross member i fab will fit which ever trans I go with.

I was looking around on CL and found this near by me...

This is a Muncie transmission in very good condition ,I switched over to an automatic so here is what is included, Transmission, clutch,pressureplate, throw out bearing, flywheel, Hurst competition plus shifter,and bellhousing. Here are the numbers on the parts M13310 3861325 Trans 6263756 Bellhousing, The clutch,pressure plate and throw out only have 2000 mi on since new

I guess I should mention that the engine I will be running is a SB 307 and that the rear end also has 307 gearing..

As most of you guys are, Im on a pretty tight budget, he is asking 800 for all the parts mentioned in the add.

What do you guys think? Good set up/ Good price? Can I do better for the money? M-21 good solid units? I tried looking around on the internet seems to be mixed reviews. I asked my old man about them, Hes no transmission expert but seemed to recall something about them having sycro issues. But he wasn't sure.

If my rambling made any since.. Im basically just looking for some help/input

Thanks guys
 
The mount is the same for the PG and the Muncie, so the crossmember will be the same. That's the beauty of late model GM units. Mock it up with the PG, and if you go with a manual later the mount won't be an issue.
 
Thanks B E D for the heads up on the crossmember... but if i mock it up with the PG... will the overall length be the same? As far as measuring for a drive shaft?
 
I'm a manual guy for life but I think that you could grab an ol th 350 or a 700r4 for pretty cheap ussually. You wouldn't have to worry about shifters out the floor either.
 
Muncie

I have an M-22 that I ran for quite a while until I wanted gas milage and put in a T-5. The PG and M-21 should be the same length, or close enough that you would not have to change driveshafts. The distance from engine to transmission mount is exactly the same. If you like rowing through gears then definitely go with the 4 speed, if however you like simple cruising then go with an automatic but not with the PG unless you are on a nostalgia kick. You can pick up a 700R4 (still the same mount location as the 4 speed) fairly cheaply and have better gas mileage.

If I had the PG I would be looking around for some of the drag racing guys in your area to peddle it. The PG is a popular choice with a lot of Pro-mod guys and you might be able to get enough to offset a good chunk on the 4 speed or a 700R4. A friend of mine uses PGs in his drag car behind 2700+ horses and swears by them (and at them when it breaks). He is running high 6s in the quarter.

For me nothing says hotrod though quite like three pedals under the dash. I grew up in a generation that learned on standards and I never quite gave them up. I'm getting ready to start on a '27 Ford coupe that will have a '39 Mercury transmission and running gear. Plus you can run a lot more radical cam easier in a standard.

Good luck on your build,
 
Thanks for the input guys, Maybe ill look into the T-5, having that 5th gear would be nice on the highway... Are there any that are better then the others, or easier to adapt to my 307?
 
Thae easiest thing to do is look for one from a IROC Camaro or Vette. The ones from an S-10 have a better shifter location but the V-6 tranny input shaft is about 1.25" longer than the regular GM trans input shaft. Ask me how I found that out while trying to install the transmission lying on my back under the truck! The Camaro/vette trans has a 6" long input measured from the front of the trans and 28 splines where as the S-10 had a 10 spline shaft about 7.25" if I remember correctly. It has been about 5 years ago when I did this. I finally gave up and took my trans (V6 Astro van) to a buddy who owns a transmission shop. He ordered the correct pieces and rebuilt mine as a V8 transmission. I had to replace everything except 5th gear, reverse and the output shaft but it has all Tremec guts now. I found that depending what your tranny comes out of the shifter may be located differently on the tailshaft housing.

Moral of the story, pay close attention to the T-5 you are thinking about using, there are more variations out there than you can shake a cat at.
 
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Thanks cb, I appreciate the help...

I did a little looking today over lunch... There's a t-5 out of 83 firebird for sale locally... I assume this would be the same one as in a camero?
 
yes and no. The 83 firebird/camaro T5 will have a clutch cable instead of a hydraulic slave cylinder. It will bolt up and work fine on your 307 and the clutch might be easier to set up. Later units (85-92) had hydraulic slave/clutch set ups. you will also need a 158 tooth flywheel and a 10.5" clutch. I am pretty sure the PG yoke will go into the back of the T5 as it is the same as th350. also with the .67 OD 5th gear and 3:08 rear gears you will be turning about 1200rpm @ 60 or abotu 1750@80mph
 
Thanks for the info jfg, those rpms would be great for getting some good gas mileage

What tire size did you base those calcs on? i will have big ol 35's out back...

I was doing a little research and some people were saying that the t-5s were only good for light weight smaller vehicles, do you think that statement is true...

heres the listing i was looking into

Selling a Complete 5-Speed Swap out of a 83 Trans Am, Everything worked fine before removal and only has 83K on it, newer clutch, Includes Transmission T5, bellhousing, flywheel, clutch, pressure plate, pedals, shifter, linkage and so forth, First $500 Cash gets
 
I put the T-5 in my roadster and it's great! I got a world class unit from a camero and put on an s-10 tail shaft to move the shifter forward. There are a few web sites on this that are easy to find. Search under T-5 swap, you'll also find charts to I.D. the gear set. It's easy! This is a great trans, its small, strong, and the parts are easy to find even it your far from home. I drive my roadster ALOT on the freeway, and the 5th gear O.D. is great!
 
Tranny

It ain"t a hotrod unless it has 3 pedals,If you are planning a lot of long road trips go with the T-5 but if you just want something to run around and play in that is a good deal on the Muncie package.:cool:
 
i would gio with a turbo 350 with those gears and 35s, unless you want to shift gears then i 'd go with the muncie it a lot stronger than a t-5. with the 3.07 gears and 35s you would not be able to use 5th gear till you were running about 80
 

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