Get the engine code off the pad behind your alternater on the block and cross referance the last three letters,suffix code, on this link--
www.nastyz28.com/spmenu.htmlFor instance, mine shows CNB as suffix code, so I click
CMK- CUD, follow the codes down to find CNB and, viola, I've got a 1970 Z28 350 with advertised 360 factory hp. Now you have to take into account that that's flywheel hp. The drivetrain takes up a bit of power, but, it gives you a really good idea at what your dealing with.
JayTater
Z28 C10