I have to be sure the credit is going to the right place on a few of the comments: I've done everything on this intake with the ONE exception of the welding, which I had to get done. I just didn't have the amps available to pull off such a job on aluminum and frankly it wouldn't have been done as well as that.
tlowe - runners are 1.5 inch. They're large compared to stock but not really excessive in light of what I may want from this engine in the future.
Design notes: That d-extrusion is way too big, about twice the plenum volume necessary for the engine. This usually has the effect of a small gain in high end at the trade off of response and sometimes low end. Given this isn't a tuned intake and neither was the stock the low end loss won't happen (never there) but the response will be a serious problem.
On the other hand I've got too much throttle for this size engine which will partly cancel out the effect of the plenum. Basically I've left these open to be tuned: because the end caps are removable I can add dead volume in there to take up space and increase response. I can also modulate the throttles through different linkage geometries and opening rates (progressive throttles for example).
So there's a fair bit of tuning to still happen here but you can see where I'm going.
By the way, just turned 22 a little while ago so if I sometimes seem a bit green its not for lack of effort
I appreciate all the support here guys, keeps me going sometimes.
