recently picked up a 79 berlinetta, its an original 4 spd car as far as i know, and have discovered it has neither the muncie, or t-10, but has the saginaw 4 spd, its a close ratio i know that, are these tranny's any good? i know the t-10's and muncies hold up good, but not sure on these saginaws, i have a 420hp 383 stroker going in the car and want to make sure this trans will hold up, otherwise i will search for something else to put in the car, any info would be appreciated, thanks

 

not a bad transmission. 420 hp might be pushing it if you get traction off the line. it was designed similar to a muncie only cast iron. if it is not a weekend track car you should be fine. the best part is they are fairly resonable to pick up if you do break one

 

Well, we managed to do some damage to a Borg Warner T10 in my Dad's '73 (bent the output shaft, cracked the case from the input shaft to the outside, cracked the bellhousing, as well as snapping BOTH U-joints ..... all in one "attempted" launch!! ) ... and that was merely behind a "mild" 355 . On a previous launch, the car ran 12.79 @ 109.72. And this was with ET Streets on the car.

SO, how will a Saginaw hold up behind a ~420 HP 383?? Well, as long as you don't let the clutch up at ~5000 RPM, you might have a chance!

I'm sure for street driving, with street tires, it will be fine (the tires should break loose before anything else "breaks" ). Start launching hard and putting sticky tires on it ... forget about it . I think you'd find that tranny would be the weak link, like the 7-5/8" 10-bolt in the 3rd/4th gens!

 

If all three shift arms are on the side cover, it is a Saginaw. The "V-8" Saginaw had a 2.54 first gear. There was no close ratio model. You could probably run 420 HP through it but I'd be more concerned about the torque from that 383. I'm not sure they still installed Saginaws in 1979 so it may have been swapped out for the T-10's they were using then. Saginaws appeared in a lot of 4-cylinder applications also. They usually had a low gear ratio around 3:1 and were proportionately weaker. Paul

 

http://www.nastyz28.com/chevy-manual...tification.php

at the top of this page, it has 3 transmission pictures labeled, i was first unsure of which i had, it seems like a very close ratio, and has a 7 bolt cover, there are 3 hookups on the side cover for shift levers, then one shift lever towards the back, maybe i'll take a picture of it and post it so you guys can have a look at it.

 

it was brought up between myself and others possibly going automatic, the car will be a street car, but will have its visit to the track a few times as well with a stall converter going in, and some slicks out back, would the automatic be a better trans for track time, or would the manual be a faster trans at the track? looking for good streetability, but the quickest et's at the track.

 

Typically, the average driver is more capable of getting an automatic down the 1/4 mile "quicker" ... if you can't launch or shift your 4-speed, you're going to have disappointing times from your car, no matter how radical you build the motor.

Then with the torque multiplication factor of a stall converter, an auto becomes almost impossible to beat .

And considering the availabilty of TH350's & TH400's, which have been around for several decades now, their reputation, price, and ease of being WELL BUILT, it's probably the "safer" option, compared to the Saginaw you've got .

BUT, having HAD a 4-speed in our '73 Camaro, and now converting it to an auto, I still wish it had the 4-speed . For the couple times we've taken it to the track, it was WAY more fun the rest of the time on the streets with a standard .

Here's an option ... find a used T56 for it .

 

thats what i was trying to debate, i will be going to the track a few times, and the automatic would be the way to go, but the car will be driven, quite frequently if it turns out to be very reliable, which would lean me towards the 4 spd, i figured it will cost about the same to convert the car to an automatic with a well built th350, as to buying a fresh muncie from a local tranny shop.

 

Price it out, weigh it out ... I'd (personally) lean to the 4-speed .

... but I don't mean this in "generalized" terms ... I mean, it sounds like YOU want to have it, so I'm just agreeing moreso .