Join Date: May 2007
Location: Baltimore Maryland
Re: Rotating Assembly Mystery
Unless someone swapped the pistons, they are probably dish. Let me ask you this, how well does it run on 87 octane? If ok, that would rule out a real high comp motor. If this is a stock 77ish, that would make you somewhere around 7.6:1 static, using stock internals. Not good at all. We all know in 71 they went from high to low compression. My stock 71 350 has a dish piston and a 76cc open chamber combustion chamber that makes around 7.6:1 static compression. Now, if someone changed the pistons, it's impossible to tell. That cam is way too big, IMO. That combined with the not so hot rear end ratio makes for a pig off the line. I used CamQuest and going with a 62cc chamber 2.02/1.6 valve head, high rise high flow intake, dual exhaust w/mufflers and no cats, 18cc dish piston, .039" thick head gasket, cylinder bore of 4.000", gasket bore of 4.125", stock deck height of .025", stroke of 3.48, an intake valve closing of 50*ABDC and that got me a static ratio of 8.6:1. I got a peak hp of 334 and a peak torque of 365. This is at the flywheel so take away about 33hp and 36ftlbs. if you use a drivetrane loss of 10%. If you use a loss of 15%, take away 50hp and 55ftlbs. Much better than if you would have an auto tranny.
IMO, that cam is too much for those heads. Not to mention that cam technology is made for newer design heads. If you would switch to something like the L-79 cam or maybe the 30-30, you would get better results. IMO, you are combining 2 different design eras. Either switch to newer heads or an older designed cam.
Charlie Knudsen 67 Camaro RS/SS 350 TKO 600, 4.10's, AFR 195 Street Heads, Comp 270H, Rhoads Lifters, Crane Ignition, Pertronix Dizzy, Performer RPM Q-Jet, Heavily Modified Q-Jet, Hooker Comp Headers, MagnaFlow 2 1/2", 144 Decibles(Alpine CDA-7998 Head Unit, RF X7 and RF 750X Amps, MB Quart Mid's & High's, Kicker L7 12" Solo Barics)