318/904 Keep or Replace?

[Darter6]

No problem running the 904. Stock racers use them all the time. Most prefer them over the 727.
Gears depend on many factors. Mostly what cam is used.I often ask what and where do you drive the most.
For me the highway speeds are 3 miles from home in any direction.So that's to say speeds are anywhere between 65-90 mph just to keep up with traffic.
The Snap-On man got lots of my dough too !

 

[Cranky]

The 904 is/was (don't know if they still are) popular with the stock class racers because they are a bit smaller and rob less horsepower. They can be modified to hold up to high powered engines. CRT (John Cope racing transmissions) can answer your questions but there are many here that can too.....