Originally Posted by mjgroves
I went back through and read the threads about 240's modded manifolds... and I'm still confused why boost decreases even though there's a clear increase in HP and torque. My brain is saying, "wait, less boost should be bad"... it needs a scientific explanation.
Also, I have a LET tune for the C3 pulley and NW dual, would I need to be retuned if I purchased these tweaked manis?
Thanks all for the responses!
Simple way to explain this is the engine flows more freely. Your increasing the volumetric efficiency and reducing the restriction in the Manifolds. This equals more power but a drop in pressure in manifold.
Bigger cams and porting work in the cylinder head would cause the same effect. Reducing pressure on the intake side with possible increases in Power. Ulitimately you would need to move up to a larger blower that pushes more CFM to see those 20+ psi and you would be making massivling more power at the same boost.