Know I'm late to the discussion but thought I'd add my two cents. Intake manifolds typically work best if there are some (not all) of the casting bumps left. The rough edges help for fuel atomization. Not sure how well a completly smooth setup is gonna work, how has it done for you? Definately looks cool.
Post by testiclease on Sept 10, 2013 1:24:47 GMT -5
This has been an on going battle over the course of the season. A battle which 2 manifolds have won. I ended up making a smaller plenum version of this one and still ran into some problems.
The problem i have had is all the mixutre flowing to the back of the manifold. At idle i would get great vacuum, throttle response was good, and sounded really good with the Holley 350. But once moving, hitting around 40 mph all the fuel/air mixture would rush to the back starving the first 3 cylinders and flooding the 4th.
My second attempt had a smaller plenum, and runners moulded into the floor. Same problem but not as bad.
My conclusion is that virtually no plenum is needed. This winter i will either try another design, or just open up a stock manifold and swing the spacer to accept the Holley 350.
I ran the season with the stock manifold and weber 32/36. Worked fine once i figured out some of the bugs in the carb, but still having issues in transition.