..........power expectations........

The Magnum engine is more then likely in pretty good shape on the inside. Build it on the side. Swap over the old style parts like A/J said and cam it. Stick with the roller. The cam is expensive, but, the swap over to a Hyd. or mechanical cam is nearly as pricey if not more. Since you have to get new pushrods at the proper length along with the cam and lifter set. It starts adding up.

If you all ready have LA intakes, you can have the Magnum heads textiles for them and save money over getting a Magnum intake.

Remember the create engine. It is a basic factory stock long block with performance parts.
Cam, intake and headers reaped a 360/380. These always dynoed over 400hp from many sources. Add 3.91's or better. The roller cam used was in the [email protected] intake duration.

I have met a few fellas running them into the low 12's. 1 guy had a race weight (AKA- stripped down naked light weight Duster) running in the 11's.) 13's should not be a problem in a full weight car.