Originally Posted by
rumrumm
I have been watching this thread, and I have a question. I am not trying to start an argument with you, techinspector1, as you have considerably more experience than I have. But I don't quite understand your recommended cruise rpm for a cam with 230 degrees @ .050 duration. Perhaps you can explain that to me because I have achieved different result. My 383 has a 230 cam [CompCams 280 Magnum], AFR 190 heads [68cc chambers], flat top forged pistons w. 5cc relief, 6 inch connecting rods, and a zero-decked block with a .039 head gasket. That equates to 10.6:1 static compression, 8.44 dynamic compression. I know that is somewhat on the edge of what pump gas will accommodate. I had it run on an engine dyno to set timing and dial in the carburetor, and its best pull was 450 hp @ 5200 rpm/468 ft. lbs. of torque @ 4300 rpm. It made the most power with 32 degrees total. It runs fine on 92 octane pump gas, it will cruise all day in overdrive [700R4] at 2100-2200 rpm without ever dropping down a gear to climb a moderate hill. But if you get much too below 1800 rpm, it is going to want a lower gear. Is this because the engine makes so much torque and the vehicle is so light? This is in a '32 Ford coupe weighing around 2600 lbs.