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.... |
jwalters |
Dec 17 2004, 11:38 AM
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#102
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Sooo Close....... Group: Members Posts: 1,677 Joined: 14-May 04 From: Huntsville, AL Member No.: 2,068 Region Association: Europe |
QUOTE(rdauenhauer @ Dec 16 2004, 08:56 PM) Im not smart enough to follow this ... (IMG:style_emoticons/default/wacko.gif) Why would the collection of intake air in a larger common cavity enhance mid & torq as compared individualm properly sized TB's? (IMG:style_emoticons/default/wink.gif) This si the same technology all the japanese bike makers use to squeeze every last iota of power from the tiny engines...point: Testing has showed and confirmed that having the largest Airbox possible slows down the intake velocity and turns it into pressure----- Further testing has shown and confirmed that the use of a decent sized airbox coupled with a large plenum has the same effect-- On these engines as well as any other high rpm / high power engine the speed of the air being "sucked" into the carbs are approaching or exceeding the speed of sound--this is not good--high velocity means low pressure, think of it as a carb venturi--by being in the transonic range ( just prior to going supersonic) and pushing thru S/S, negative pressure waves develope which can in the right instance actually stop and restart the flow of air up to 100k times per second. Which gives very poor performance and causes aircraft jet engines to " flame out" i.e.-...not run at all. Too much velocity is bad juju----- (IMG:style_emoticons/default/wink.gif) |