Head Porting Sticky
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Teching In
Joined: Sep 2019
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From: King N.C.
Head Porting Sticky I have a couple sets of heads I want to clean up, 243/L92. I am very familiar with SBC port matching, etc but not with LS heads. I thought I saw a sticky on porting but unable to find it. Is there a sticky or good link to cleaning up LS heads?
Thanks,...Alan
Thanks,...Alan
Banned
Joined: Oct 2020
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https://ls1tech.com/forums/generatio...ng-sticky.html
Several links and lots of info in here for a DIY guy.
Several links and lots of info in here for a DIY guy.
TECH Addict
Joined: Dec 2017
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Any good porter will tell you, don't bother with "port matching" until AFTER all the stuff that REALLY matters, is perfected.
In my experience, about 75 - 80% of all porting benefits come from right around and near the valve and its features. Cleaning up casting parting lines in the lower part of the port, bowl smoothing from where the factory just sort of jammed their cutter down into there and left all kinds of steps and angles and whatnot, guide shaping, valve job (multi-angle or radiused), backcutting the valve margins, using necked-down stem valves, unshrouding where the edge of the valve comes too close to the "side" of the chamber, etc. About 10 - 15% comes from smoothing and straightening the side surfaces of the port that the gases run against, and sometimes, on the exhaust, raising & rounding the top of the port slightly. The rest, if any, MIGHT be available by port matching.
"Port matching" is almost always nothing but useless eye candy, applied to distract the uneducated by showing them shiny things.
LS heads are no different in this regard from any others.
In my experience, about 75 - 80% of all porting benefits come from right around and near the valve and its features. Cleaning up casting parting lines in the lower part of the port, bowl smoothing from where the factory just sort of jammed their cutter down into there and left all kinds of steps and angles and whatnot, guide shaping, valve job (multi-angle or radiused), backcutting the valve margins, using necked-down stem valves, unshrouding where the edge of the valve comes too close to the "side" of the chamber, etc. About 10 - 15% comes from smoothing and straightening the side surfaces of the port that the gases run against, and sometimes, on the exhaust, raising & rounding the top of the port slightly. The rest, if any, MIGHT be available by port matching.
"Port matching" is almost always nothing but useless eye candy, applied to distract the uneducated by showing them shiny things.
LS heads are no different in this regard from any others.
TECH Senior Member
Joined: Jun 2016
Posts: 22,306
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From: Central Cal.
^^^This, but the main focus is NOT to increase area, but to smooth the flow, which bowl blending and a GOOD multi-angle valve job will do most of, besides cleaning out zits and hiccups from sloppy casting. Rectangular port heads, especially, do not need any opening up, as they support close to 600 HP untouched.
