What mods for my 904 when using the BPE 408?

rumblefish360 said
What flex plate should be used? Neutral or weighted?
Thanks

Phreakish said
BPE strokers use 360 weighted flywheels/flexplates and magnum weighted balancers (which are different from 360!).

Details are listed on the shortblock page under rotating assembly:
Mopar 408CI Stroker Crate Engine | Small Block Chrysler | Shortblock

Assuming the converter is neutral, as most aftermarket ones are, then Yes, you use an LA 360 balanced flexplate.

The Balancer (which we sell for under $90, and include on most dressed engines) uses the magnum weight for our engines)
Mopar Small Block Harmonic Balancer | 273 | 318 | 340 | 360 | 408 |

if its purchases on its own, it comes with various weights for all SB balances.