 /4 head question....modify exhaust side only???, for stock or near stock cams...... |
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| Mueller |
 Nov 22 2004, 09:01 PM
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914 Freak!  Group: Members Posts: 17,146 Joined: 4-January 03 From: Antioch, CA Member No.: 87 Region Association: None 
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So I was thinking, (oh no Mr. Bill (IMG:style_emoticons/default/ohmy.gif) ) the exhaust side of the /4 heads is supposed to be the main weak link when it comes to getting any decent power gains from the type IV motors.....the ratio of what the intake flows compared to the exhaust is too lopsided (the exhaust should flow 75%-80% of the intake or something like that to be ideal?????)
If one was to keep the stock cam (not really keen on splitting the case) and just install a much larger exhaust valve and re-work the exhaust port only, would it make any appreciable difference?? This is for a 1.8 motor with a European racing header.....otherwise all stock...currently D-jet, but that can be changed (IMG:style_emoticons/default/smile.gif) (IMG:style_emoticons/default/smash.gif) |
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Posts in this topic
Mueller /4 head question....modify exhaust side only??? Nov 22 2004, 09:01 PM
SirAndy <... Nov 22 2004, 10:17 PM Brad Roberts HUm... :idea: *somebody* you know has been askin... Nov 23 2004, 01:03 AM Mueller I'm going to try to get to whats-his-names sho... Nov 23 2004, 01:07 AM Mueller <... Nov 23 2004, 01:08 AM Brad Roberts I'm working a guy in Mountain View for "use" o... Nov 23 2004, 01:49 AM chunger What happens to a type IV if you make the exhaust ... Nov 23 2004, 02:11 AM Rgreen914 <... Nov 23 2004, 02:46 AM chunger oops NO2 the stuff that turns into N and O2 and ha... Nov 23 2004, 04:40 AM
Mark Henry A big valve doesn't help much if the port is s... Nov 23 2004, 07:32 AM  |
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