[Steve C.]

From the internet.... While longer runners tend to work well at the lower rpm range, shorter runners favor the upper range of the rpm band. Plenum size also has a dramatic effect on power production. Smaller plenums, like those in a dual-plane manifold, do well in the lower rpm range while larger plenums, like the single plane manifolds, tend to boost the top end of the rpm range.


As cast average runner length:

Performer RPM intake - 6.28
Torker II intake- 6.06
Victor intake- 8.82

As cast average plenum volume (cc):

Performer RPM intake- 1400
Torker II intake- 1195
Victor intake- 946

( My 4150 Victor intake has no plenum work, only a port match and light runner blending. It has supported a 4.125" stroke/450 CID combo at 7000 rpm with 684 hp. With a Brad Urban Carb Shop Stage III Holley 750 carb )


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