Not in an aerodynamic 3000 pound car, but have a read of what this guy is running, it's a heavy truck with the aerodynamics of a brick...a very big brick.....running through an auto, and a choked up exhaust system, with an efi distributer curve, dual plane intake and has practically no quench or compression, and has a top end cam with a lsa wider than the grand canyon. How does that saying go...."you can't make a silk purse out of a sows ear"...or "you cant polish a turd" but you can roll the turd in glitter by at least freeing up some flow through a half decent exhaust system. Students generally don't have a lot of cash flow so most answers have taken this into consideration. If I were the owner of this combo and had no cash I would rig up a passive water injection system which would allow a better advance curve without running into pre-ignition problems, and just thrash it until it blew a hole in the block. Until that time came I would re-ring the original engine that had more power and got better mileage even though it has horrible blowby and refit it.Truckedup wrote:A lot of discussion about choked up exhaust affecting fuel mileage. Does running down the road at part throttle create that much exhaust volume???
Surely with a dual plane manifold there shouldn't be any lope present?At an 800 rpm idle, this thing is a little rougher than I think it should be (at least until I found out that the seat to seat timing was so long). It actually has a slight lope to it.
" Flat" lobes generally still lift the valves, just not very high, I would be looking for a tight lobe separation angle cam, around the fore mentioned Vizard specs.All the valves are moving...so no flat lobes
I would also check the distributer for shaft play, vertical play means constantly shifting timing leading to a lopey idle.