What transmission should I use here?
I have a 1995 LT1 engine that I want to install in my 1938 Chevy and I’m wondering what transmission is the best fit. The rear end is out of a 1975 Firebird.
You don’t say whether you want to install an automatic or a manual transmission. Either way, I would suggest using a transmission that would have been coupled to your LT1 engine when it was new. There are various OEM transmissions that fit that description.
If you want a manual gearbox, you can go with a Borg-Warner (Tremec) 5speed. These are plentiful and relatively inexpensive. Though usually somewhat more expensive and perhaps not quite as common as the T5, another good choice is the Borg-Warner T56 6-speed manual box. Like the T5, these were used in a wide range of vehicles, including Camaros, Firebirds, Corvettes, Mustangs, Vipers and various trucks.
If you want an automatic transmission, a 700R4 or 4L60 is the obvious choice. These are robust and extremely plentiful.