Common plenum or individual runners???, for gas milage and drivability |
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Common plenum or individual runners???, for gas milage and drivability |
Mueller |
Dec 16 2004, 10:04 PM
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#101
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914 Freak! Group: Members Posts: 17,146 Joined: 4-January 03 From: Antioch, CA Member No.: 87 Region Association: None |
for my 2316 it seems that the stock plenum might be reaching it's limits as far as volume goes.....so, I either fabricate a larger common plenum, or go with individual throttle bodies such as TWM or Jenvey*
single plenum would be easiest, but the individual throttle bodies look better (IMG:style_emoticons/default/smile.gif) has anyone switched from one to the other on the same motor with everything else being the same??? *Jake Raby is the U.S. distributor of these.... |
lapuwali |
Jan 20 2005, 04:41 PM
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#102
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Not another one! Group: Benefactors Posts: 4,526 Joined: 1-March 04 From: San Mateo, CA Member No.: 1,743 |
Now you've killed one advantage of a single TB: no throttle synchronization required. The only advantage I can see to a smaller TB on a large plenum is less throttle sensitivity at small throttle openings. Intake velocity across the TB seems to be completely unimportant unless there's a lot of other resonance tuning going on, but this is all black magic to me. Velocity in the runners I see as being much more important. Shortening them is going to raise the power curve higher in the rev band (according to the usual theories, anyway), and you're building a big, torquey engine. So, it seems that's to cross-purposes to me. 64mm is bloody huge. Compare this to the 2x28mm restrictors required on all DTM cars. That's a total area of 200 sq.mm for the Honda v. 176 sq.mm for the 475hp V8s used in the DTM. The Accord certainly doesn't need that big a TB for flow, so they must be using it for some other reason. |
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