66sunset

Hey Guys, I'm new to the site. I saw a discussion about installing overdrive transmissions into C2 & C3 Corvettes. I have a TH400 I took out and I want to install a 4L80E in place in 66' Corvette. This is going behind a big block 509. Any advice? Will the converter for TH400 work in a 4L80E?

tfi racing

iTrader: (2)

Have a look over at the corvetteforum.com,likely more than a few swaps over there,I think you may have to make some mods to the floor,you will need a 4L80E converter.

superdave84

A converter for a modern transmission has TCC lockup which the old style converters don't have. In addition to that, I imagine the spline count and depths are completely different. You will need to get the correct converter for the new trans.

I know it will bolt up to the block, but I don't know how it's going to be controlled. It's also larger, and will require moving or modifying the transmission crossmember, and likely some modifications to the tunnel will be needed as well.

The TCC is controlled with a switch on the brake pedal (same as what turns on the brake lights, but with an extra part to the switch. Again, without an ECM or separate TCM, I don't know how this would function.