20+ years of "Building 904/727 for drag racing use"

rumblefish360 said

In reading all of this information, I have a few questions!

Between the 904 & 727, there comes a point where parts, for ether, become limited. Between the two;

Which one would be the better choice for a 9 second ET car.
(In my case, it would currently be a small block Duster being built.)

Ultimately, which one can hold more power?

Where are their respective Tq. & HP limits?

Click to expand...

There are a lot of things that need to be known about the combination, but I'd typically recommend a 904 for a small block powered car that is lighter with smaller tires. A 727 will of course work fine, but it will be slower than a 904. My footbrake 727 in that car at that ET would go 1500+ runs before needing a freshen up. Freshen up intervals on the 904 would be shorter. The 904 would cost slightly more to build than a 727 for a 9 second car.

Obviously, the 727 can hold more power than a 904.

For conservative numbers we will build a 904 for 1000hp, and a 727 for 1500hp. The blue supercharged Challenger that used my 727 made more than 1500hp.