Friends and whatnot have been nudging me and telling me to put in a 289 in my car (a goal that's a long way from being accomplished), but I've been getting different variants of this from different people.

Some are saying that the transmission for the '66 200 and '66 289 are the same, and others are saying they're different.

If I were to throw in a 289, would I still be able to use the tranny I have now, or would I have to get a different one?

 

I'm not a trans guy, but I'm told by those who are that certain internal parts of the 200 version of the C4 are not as durable.

 

Manual transmissions are different as well

 

The same transmission is used for both the 200 and the 289. The difference is the number of clutches and the settings in the valve body. The C4 for the 289 contains up to 4 more clutches than the same transmission in the six. the pressures can be lower or higher depending on the set-up of the car but as a general rule pressures in a C4 fo a six will be higher when in manual gears and lower in drive with modulator pressures being lower and the modulator set to shift a bit sooner.
From the outside the only difference is the bolt-on bellhousing and the smaller converter.

To answer your question directly:
Yes, you can use the same transmission but you should not expect it to live very long with the added torque and hp. I would advise you to get a 73 or later C4 for a 302 to use with your engine swap.
If the engine is stock, and you install a TransGo reprogramming kit and a large cooler it will optimize either for longer life and better performance.

 

So could a V8 C4 fit on a 170 or 200 inline six? just killed my 3 spd non-snycro manual. I've got a little 3 spd automatic I'm looking at installing but still going through my options. I'll most likley make my own post for this anyhow. after using the search bar. lol