Tallguy Some of the cars have brakes that lightly drag on the rotors. Total power loss is about 22-24%. Exhaust side pipes are the biggest killer of all. If you go with a race muffler you will have less backpressure and make alot more noise. The power loss will be 5-10 HP instead of 20-50 HP depending on what muffler is used inside. My ERA pipes pass the noise police at racetracks and are a glasspack inside with good sound. After some racetime I get the ringing in the ears. I now wear ear plugs the the problem is stopped. I have racepipes and they are loud. It's all about backpressure. The idea number is about 1.5-2.0+ pressure in the system at WOT. Anything more and you are wasting power. The other thing is that if you are going to build an engine like your 428 add a stroker crank of 4.25. TORQUE is what moves your car, HP is what keeps it going at top speed. Unless you are racing and turning 7000 rpm, don't worry about how much HP you have. The correct gearing in the rearend and trans will offset a car with 30-50 HP more than you. I have a 452 motor 9.2-1 compression,501-533 hydro cam,5spd, 3.31 gears, the car runs 12.5 all day long at 108-109mph. I am easy on the jag rear, it is not a good drag racing rear. 368 rwhp and 458 tork rear wheels. Car idles at 700 rpm smoothly and pulls to 5,800 rpm hard, I don't like to spin motor over 6,000 rpm, it is out of power by this time. Stroke the motor with a set of BBC rods and 4.25 crank and find a nice cam in the .550-575" lift. hydro lifters are fine and are maintainance free on adjustments. Add a accusump system to your car and use it as a peroiler. 80% of engine wear is on startup.
Have a little port work done to the heads and you will have a 400-450 rwhp car. This is a nice combo and still drivable. You car will be like most here, a work in process. Buy a good rocker setup like ERSON. FE shafts break, even the heavyduty ones. Rick L.