Intake Plenum Volume

[Paul Workman]

Originally Posted by XfireZ51

The C5 and C6Rs have used split plenums for some
time. The Ford SHOs did also.

Originally Posted by Paul Workman View Post
I'm fascinated by the physics involved. So, in lieu of any expertise in flow dynamics, I'll just sit in the front row and...... Maybe flyin Ryan will step in and share some of his experiences? (I wish someone would turn over a "hole" card!)


Just to add a log to the fire, I noticed too that the new Ford Coyote motor uses a split plenum.

P.

PS,

And, the runners were straightened out - by design, or as result of the split plenum?

One area I have been able to ascertain concerns runner lengths - a source of fascination as part of porting to derive a particular outcome. Most realize that like pipes in a pipe organ, runner length directly affects the frequency of the resonating air column within, affecting the engine's output in a significant way. To what extent the plenum metrics plays a role...that is the question.


P.

[LGAFF]

Dom, although the plenum is split, the total volume is large......you are essentially creating 2 4 cyl engines.....so the plenum volume relative to the CI of the 4 cyl is what you need to consder. Once again, the larger the plenum the less impact of harmonics(thus it acts as a split plenum to some extent) I am going to be doing some testing once the engine is done and dyno'd. That includes some internal plenum changes.....

However if you divide a plenum that is already too small...could have a very negative(and expensive) effect.