If you were going to stroke the motor to 393 you will need aftermarket heads and a minimum of the allusive #5752425 4100 along with sometype of header other than the cast manifolds or you are just wasting money.....................................................................IMHO
I'd have to agree on the xhaust for sure since there would easily be 30 horse left on the table with thos manifolds no matter how hard you work them to paper thin. those particular heads can be worked to better than many think compared to an out of the box AL.. but the cost would be extremely prohibitive if they can't be worked for free. 500 horse is there.. but it'll take time, well over a pound of whittling, a bit of putty.. and cost ya more than it's worth to do it.
Hmm, I was always of the belief that there was approximately a 60hp loss between flywheel and axle due to power transfer; have I been wrong for years now?
There really is no set figure and depends on the combo and drivetrain mod's of course. Slushboxe's just consume more HP compared to manuals, is all. And not all of those are created equal either and then there's the TC slippage to consider as well. Between 10-20% loss.. is about average when generalizing on such things, IMO.
