modifying intake manifold, how high should it be
modifying intake manifold, how high should it be
(OP)
I have a 6.1 liter dodge hemi, i need to modify the intake manifold to accept a twin screw or roots blower. I want to keep the height above the hood as low as possible, so my question is, when cutting the manifold is there a minimum height it should be for performance, or does it not matter?..right now the runners are about 4-5 inches high, if i cut them to 1" ..will it work..thanks





RE: modifying intake manifold, how high should it be
Mike Halloran
Pembroke Pines, FL, USA
RE: modifying intake manifold, how high should it be
Also blower manifolds can expand quite a bit due to heat from the air being compressed (depending on boost level and what fuel and where it's added). This can change belt tension quite a bit.
Runner length and plenum volume are much less important with a blower, but runner cross sectional area should be maintained. Air flow from the blower discharge point into the runners should not be obstructed and should have reasonable radius and some bell mouth shape if possible.
If you look at street and race manifolds for more common engines (like small block Chev) you will get some tips.
Race manifolds are designed to optimise performance above all else.
Street manifolds make a reasonable compromise on performance for the sake of convenience, particularly with regards to mounting height.
Are suitable engine internal parts available for the boost and power levels you intend.
Mikes point re actually being able to access mounting bolts is very important.
Also access to other regularly serviced engine parts is important, like ignition system and tappet covers.
Take care not to obstruct water flow from the heads as cooling may be more critical.
Regards
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RE: modifying intake manifold, how high should it be
RE: modifying intake manifold, how high should it be