tooter's manifold adventure...

[Blown_xa]

Great read. I applaud the effort put into the manifold and testing it. I wouldn't be dissapointed at all, Ive seen reputable companies produce manifolds which proved power loss much greater. You have the right design aspects in your manifold design for the goals you had in mind. If I were to guess, a header will compliment that manifold simply because the volumetric efficiency of the intake has increased so much. You may not have a gain now because your setup is ''lopsided'', hiding the potential of the manifold.

As far as dyno conditions, that sheet clearly states the numbers are SAE corrected... which means temperatures and barametric pressure is accounted for. ( you can dyno on a 30 degree day, and on a 90 degree day, the numbers should theoretically be the same if SAE corrected).

VVT I on our cars learn, and change according to driving habit. I put my car on our dyno once with no changes, It made 28ft. lbs more torque, 6 less hp.........no changes. So I would deem your results inconclusive until you switch the manifold right on the dyno.