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Author Topic: Head porting without flow bench: waisting time & money?  (Read 10891 times)

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Offline crazypj

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Re: Head porting without flow bench: waisting time & money?
« Reply #25 on: November 13, 2006, 11:16:42 AM »
Quote from: Jay B on November 13, 2006, 10:34:16 AM
Really interesting thread, esp. since I'm going to try this on my 350f soon. A couple questions- Would it work to leave more material on the downstream side of the valve guide, ground into more of a boat tail shape to smooth airflow past the guide, or are you just better off without it?

Yes and no.
It can smooth flow but also act as a flow diverter and prevent (or enhance) the direction of main gas stream.
http://en.wikipedia.org/wiki/Cylinder_head_porting#Wave_Dynamics
http://www.se-r.net/faq/articles/head.tech.html
PJ
« Last Edit: November 13, 2006, 11:18:57 AM by crazypj »
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Offline maksuttt

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Re: Head porting without flow bench: waisting time & money?
« Reply #26 on: November 13, 2006, 12:07:15 PM »
Quote from: Jay B on November 13, 2006, 10:34:16 AM
Maksuttt, did you do anything with the combustion chamber around the intake valves, or leave it be?

I have 1975 F model and chambers have almost nothing to improve (if compare to older models). I just removed imperfections without removing any real material. Gonna polish it in nearest future.
BTW, iteresting link!!! Thanks, crazypj!
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Offline Bob Wessner

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Re: Head porting without flow bench: waisting time & money?
« Reply #27 on: November 13, 2006, 01:38:46 PM »
Just curious, what does this polishing garner in the way of performance and how to you measure it?
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Offline MRieck

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Re: Head porting without flow bench: waisting time & money?
« Reply #28 on: November 13, 2006, 02:32:49 PM »
Helps retain heat. Higher exhaust gas temps(slighty).
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Offline maksuttt

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Re: Head porting without flow bench: waisting time & money?
« Reply #29 on: November 13, 2006, 03:42:41 PM »
Also, less carbon buildup... I like polished piston domes too ;D
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Offline sparty

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Re: Head porting without flow bench: waisting time & money?
« Reply #30 on: November 14, 2006, 05:37:26 AM »
Does anyone have a before picture of their ports before the surgery?

Sparty
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Offline MRieck

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Re: Head porting without flow bench: waisting time & money?
« Reply #31 on: November 14, 2006, 05:50:22 AM »
Quote from: sparty on November 14, 2006, 05:37:26 AM
Does anyone have a before picture of their ports before the surgery?

Sparty
I have posted them before...a while ago. I'll see if I still have them.
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Offline MRieck

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Re: Head porting without flow bench: waisting time & money?
« Reply #32 on: November 14, 2006, 05:55:53 AM »
 These are uncleaned but you can get an idea.   http://www.sohc4.us/forums/index.php?topic=6795.0
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