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HybridZ

M-21 from a 65 chevy


Phyte

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Would it fit with the JTR setup? I've searched, and some said you'd have to mod the trans tunnel, and others said it would bolt up. I know about the hydrolic throw out and all that, I just need to know if it will fit or not.

 

Yes I know I won't have OD, but thats not a problem. T-5's are just too weak, and T-56's are just too expensive :D I had a 76 stingray with a muncie tranny and the driveability was just find.

 

Phyte

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The 76 Stingray would have had a BW Super T10. 1974 was last year for the Muncie. Most likely it would have had a 2.64 first gear. I really like my ST10.

 

The M21 has a 2.21 first gear while the M20 has a 2.52 first gear. IMO, the 21 is virtually useless except in a road racer. It has the distinction of being the closest ratio production 4 speed ever made (along with it's beefier cousin the reduced helical angle M22 "rockcrusher".) 4.10 is about the minimum gear to run, but 67-69 Z/28s came with 3.73 and the M21. Any gear less than 3.73 came with the M20.

 

The 4 speed trans will fit easily in the trans tunnel as they are quite compact. The exception may be the side mounted shifter requireing clearancing. If you look in the JTR manual, they have a pic of the "mule" car of theirs with a 4+3 (the front half is virtually identical to the ST10 in your old Stingray) you can compare. The back end of which is a LOT bigger because of the OD. If I were to do this swap, I would use a bellhousing from an 84-88 Corvette with its hydraulic slave cylinder setup.

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The 76 Stingray would have had a BW Super T10. 1974 was last year for the Muncie. Most likely it would have had a 2.64 first gear. I really like my ST10.

 

The M21 has a 2.21 first gear while the M20 has a 2.52 first gear. IMO' date=' the 21 is virtually useless except in a road racer. It has the distinction of being the closest ratio production 4 speed ever made (along with it's beefier cousin the reduced helical angle M22 "rockcrusher".) 4.10 is about the minimum gear to run, but 67-69 Z/28s came with 3.73 and the M21. Any gear less than 3.73 came with the M20.

 

The 4 speed trans will fit easily in the trans tunnel as they are quite compact. The exception may be the side mounted shifter requireing clearancing. If you look in the JTR manual, they have a pic of the "mule" car of theirs with a 4+3 (the front half is virtually identical to the ST10 in your old Stingray) you can compare. The back end of which is a LOT bigger because of the OD. If I were to do this swap, I would use a bellhousing from an 84-88 Corvette with its hydraulic slave cylinder setup.[/quote']

 

Mike, thanks for the info. What other trans would you recommend? The engine I'm putting in will have 453ft/lbs of torque at 3500rpm. I would really like a T-56, but I'm not sure I want to pay $1500 for a transmission. If it comes down to it I'll just spend the money and get a T-56 though.

 

Phyte

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How much and what type of driving do you do? FInd out if the Muncie you are talking about is an M20 or 21. Most likely in a big car it is an M20 wide ratio box which is the better street box. There are several Muncie decoder sites out there, including http://www.gearzone.net (which is also http://www.5speeds.com) If it is just a weekend car with no interstate trips, an M20 or Super T10 with a 3.70 or even a 3.54 diff is a tolerable setup. A world class T5 will stand up to street driving and even some mild street strip stuff. Some of the mustang guys run 11's for a short period of time on T5's. But if you break it once, the T56 is cheaper. After having recently driven a T56 for the first time, it's hard to do much better.

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Guest Nic-Rebel450CA

Regarding drivability, with that kind of torque you can easily get away with the higher gear ratio rear-end. If you could get a 3.5 R200 you could have excellent drivability and no need for an OD. Heck, I have a 3.96 R200 and rarely use OD, 1:1 at 3800 RPM is fine for me :-D Contrary to popular belief, having the lowest RPM possible at freeway speeds does not always get you the best gas mileage.

 

If you want a very stout 4spd, you might consider a Ford top-loader 4spd with an adapter, that is what I will probably use in my Z. It is also not very expensive (especially in my case, which is free). Of course, if you are an all-or-none Chevy guy, then this probably isnt an option.

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I certainly don't want to get into a T-5 then break it. I want to build it strong from the beginning. The trans is an M-21. I think with a 3.5 r200 it will be just fine on the street and on the highway. Besides both the M-21 and M-20's 4th gears are 1.00. Just 1-3 is different. I'm getting the trans cheap. I'll put it in and drive it for a year. If I don't like it I'll sell it and put a T-56 in it.

 

As far as driving its just going to be daily driven to my job. I'll rarely take it on trips, because with two kids thats what our minivan is for!

 

Phyte

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