I used to get about 2500 miles to the Saginaw in my 75 Camaro in the 70s, I did the same swap with same results.,My best friend now sadly gone bought his first new car a 1966 chevelle 275 or 300 hp 327 can't remember how it came from the factory Saginaw 4 speed exploded the trans at least 3 times in the first year swapped in a Muncie & didn't have enough power to break & it ran pretty decent after adding a L79 cam not a fan of Saginaw 4 speeds unless you want to lite foot it all the time.
When doing a rebuild, replace the open main bearings with Japan or USA made Sealed Bearings - (metal seal). The original open bearings allowed minute metal particles and chips to enter the bearings, with bad results. Also replace the wavy Thrust Washer with a Torrington bearing. Doing this will make the Saginaw much stronger. There are books out by Paul Cangialosi that go into great detail about how to modify and upgrade Muncie and Borg Warner 4 speeds. 99% of what he describes you can also do with the Sag 4 speed. Every concievable part is still available from numerous sources.The sag is an excellent low dollar four speed as long as you are not abusing it. It’s as simple as that. They are at least as strong as, if not stronger then, the stock three speed transmission. They are inexpensive to purchase, easy to rebuild at home, and have been successfully used in trifive cars for decades.
I purchased one in 2014 for 250 and I have seen them on eBay recently for 400-450. A decent rebuild kit is $100 and if you need forks, probably another 120 or so. Paint, degreaser, hardware, you have a four speed for 650. You think you can do that with a Muncie or T-10? No way. So if you have to be conservative with your funds, the sag can be a good choice.
On the other hand, if you have big giant horse power, big meats, want to do hole shots and other similar acts and abuse, the sag is not for you.
hahahaaaa....well said....at least you KNOW your limits....I've had them before in back of 327s of about 300 HP and they held up. My Mechanic says they are good transmissions for drivers who enjoy a manual and don't think every drive is a competition to prove something. Mine is a fresh rebuild with a hurst shifter and was very smooth shifting. It would not hold up with the 355 and the way I'll drive at times. I was hoping for wisdom to come with old age but I still drive like 17 at times. I think it's a little late for wisdom at this point, so I need stronger components
Likely a LOT more profit margin as well.Chevy was a lot more conservatives on when they used a Saginaw more like about 200HP or more got you a Muncie or a Super T-10 after 73..