440 Transmission

[Merrill Davis]

I have a 72 Dodge Challenger with a 340 727 transmission. I plan to replace it with a 440 and a big block 727. What is the difference? What should I expect? What do I need to know about this to save me some headache later? What is the difference between a 727 small block and a 727 big block, basically? Does anyone have a spare 727 or 904 transmission?

MDavis
Stantonsburg NC

 

[tonysrt]

Small block and B block have a different bolt pattern. So cannot be swapped big to small block.

 

[moparleo]

The 440 will make the car more nose heavy than it already is. This will hurt braking and cornering. Generally the lighter a car is and closer you get to a 50/50 weight distribution the better it performs. That is why the AAR and the T/A run a 340 and not a 440. To make this conversion though, expect to replace the torsion bars, radiator as well as belts ,hose, mounts, preferably an engine harness for a 440 or extend the wiring with splicing. You didn't say if you have disc brakes, or power brakes, both would be a good upgrade if you don't have them. Driveshaft, exhaust, bigger fuel lines 3/8 in place of the 5/16.
Tom Hand's guide to the Chrysler torqueflite automatic transmission
I have more if you need it. Happy reading.