Intake manifold construction

[vex]

Originally Posted by drewski86

I would build off a stock S4 lower manifold as it already has good transitions to the shapes of the port runners. Depending on how big your ports are going to be, you can hone out the stock lower and it should flow plenty. The EP guys are making good power (rumors of 220+whp) with monster streetports on full S4 manifolds with only internal modifications.

Still looking for the mating flange though. I plan on keeping the stock LIM for the moment, but I'd like to re-do the Itermediate and Upper Intake manifolds so that means I'd need a flange to mate to the LIM, pipes to run to the plenum then to the TB.

I haven't been able to find the flange, even though I know I've seen them before. I just can't remember where.