when I was running my set-up I tried 3.23, 3.55, 3.91 gears. anything lower than a 3.23 didn't do anything. baffled by that the chassis dyno told the story. the engine was quitting around 4300rpm; went thru traps at 4300rpm with 3.23's, anything else was over gear. back in the day there was a dyno shop we'd go to and we all noticed that the engines/chassis combo's made far lower horsepower numbers at the wheels at much lower than max rated horsepower rpm. we were always baffled by this and didn't know how to explain it. I understand it all now. what an engine does on an engine dyno is one thing; what it does all hooked up to accessories/full exhaust/drivetrain is another.


all cam changes did was fatten up the torque curve with maybe a few more horses. I tried the stock magnum cam, comp cams 268/276 magnum replacement, 272/.455, and the engle 2330; engle performed best. the summit 6401 I later tried with the stock 4bbl set-up would have been very promising and may have been ideal for cast exhaust manifolds. the 6401 isn't made very well but does outperform it's price. howards has those lobes and could make a more accurate camshaft.