Brought to you in part by:

Great deals on auto restoration supplies!

.


  Mustangsandmore Forums
  Ford Racing
  Head porting question

Post New Topic  Post A Reply
profile | register | preferences | faq | search

next newest topic | next oldest topic
Author Topic:   Head porting question
stang106
Gearhead

Posts: 786
From: God's Country!... Port Alberni B.C. Canada
Registered: Jul 2001

posted 04-14-2002 01:42 AM     Click Here to See the Profile for stang106   Click Here to Email stang106     Edit/Delete Message   Reply w/Quote
After narrowing the guides on my new World Jr's and cleaning up the casting, its apparent that the intake long radius is formed in a smooth curve. So why do all the performance porting books and articles I've read deepens the intake long radius turn and disrupts this smooth curve? I am after good mid-range velosity here as opposed to higher top end flow. Do these deeper ports work better with top end only or also at 2,500 - 5,000 RPM?
Thanks,
Dave

IP: Logged

stang106
Gearhead

Posts: 786
From: God's Country!... Port Alberni B.C. Canada
Registered: Jul 2001

posted 04-17-2002 03:26 PM     Click Here to See the Profile for stang106   Click Here to Email stang106     Edit/Delete Message   Reply w/Quote
Anyone? John? Kid? Mike? Alex? Or is this a little known area? From what I know, some ports do flow better with the long radius turn on more of an angle, depending on valve angle. Should I phone World Products with this? Thanks,
Dave

IP: Logged

[email protected]
Gearhead

Posts: 935
From: Lakewood, CO, USA
Registered: Jun 2001

posted 04-17-2002 04:10 PM     Click Here to See the Profile for JCQuinn@work   Click Here to Email JCQuinn@work     Edit/Delete Message   Reply w/Quote
Dave
I didn't answer this before because I have no experience with the World Jr's.

I have read a lot of the theory books and they seem to make sense but when flowing heads I have noticed that the air flow at seems to skip across the top of the valve and the majority of the air enters the cylinder at that point. I experimented with different port flow shapes and did not make a significant difference in the flow pattern.

To clarify, skipping across the top of the valve means entering the cylinder on the side of the valve that touches on the port roof radius.

The majority of improvement that I found using stock castings came from using larger valves, removing the ridge between the machined area below the valve and the port cast surface, and minimizing the guide/valve stem area.

Trying to significantly reshape the port floor never seemed to show large improvements. The most important feature of the port floor was trying to maintain a constant radius by smoothing out the ridge left by the valve pocket machining.

Keep in mind all of this work was done on factory castings. I have been retired from racing for a long time and never worked with the modern aftermarket stuff.

I definately would talk to the World Products people but keep in mind that you don't usually get to talk to the design engineers.

John Quinn

IP: Logged

stang106
Gearhead

Posts: 786
From: God's Country!... Port Alberni B.C. Canada
Registered: Jul 2001

posted 04-17-2002 06:50 PM     Click Here to See the Profile for stang106   Click Here to Email stang106     Edit/Delete Message   Reply w/Quote
Thanks John,
I'll give them a try after my last modifications, The other unknown-to me- is just how much cast material to leave on the port side of the exhaust 60 degree surface? Vizard seems to prefer to grind flush on the short side radius. I took mine to almost flush and blended it around. This is how I will try mine at the 1/4 for this year.
Dave

IP: Logged

kid vishus
Gearhead

Posts: 6590
From: middle of NC
Registered: Oct 2000

posted 04-17-2002 07:49 PM     Click Here to See the Profile for kid vishus   Click Here to Email kid vishus     Edit/Delete Message   Reply w/Quote
I didnt answer since almost all of my porting experiance has been on cleveland heads, and a few aftermarket sb chebbies. O just figured it is better to stay quiet than guess and give a wrong answer.

IP: Logged

stang106
Gearhead

Posts: 786
From: God's Country!... Port Alberni B.C. Canada
Registered: Jul 2001

posted 04-17-2002 09:23 PM     Click Here to See the Profile for stang106   Click Here to Email stang106     Edit/Delete Message   Reply w/Quote
I wasn't trying to guilt-trip you guys-no need to explain why no answers. I had thought that there may be general "dos and don'ts". You guys have been-there-done-that and I am attempting to learn the easy way, not from expensive mistakes. As always, I appreciate the tutorials I read from all posts. I do know that port design can vary depending on the application, so what may work well with an all out race application may not apply to mine.
Dave

IP: Logged

n2oMike
Gearhead

Posts: 2831
From: Spencer, WV
Registered: Jan 2001

posted 04-17-2002 10:22 PM     Click Here to See the Profile for n2oMike   Click Here to Email n2oMike     Edit/Delete Message   Reply w/Quote

http://www.sa-motorsports.com/diyport.htm

Here's a good guideline for porting, along with plenty of pictures. It should be just about right for those WP heads.

Good Luck!

------------------
Mike Burch
66 mustang real street
302 4-speed 289 heads
10.63 @ 129.3
http://www.geocities.com/carbedstangs/cmml_mburch.html
http://www.fortunecity.com/silverstone/healey/367
http://www.mustangworks.com/cgi-bin/moi-display.cgi?220

IP: Logged

SundanceKid
Gearhead

Posts: 1274
From: UT
Registered: Feb 2001

posted 04-19-2002 03:30 PM     Click Here to See the Profile for SundanceKid   Click Here to Email SundanceKid     Edit/Delete Message   Reply w/Quote
You want the short side radious as big and long as possible. That is what the windsor's are trying to accomplish. The books you have read more then likely are trying to remedy a less then ideal port shape to make it flow better at the top end with little reguard to low lift flow and velocity. When I port heads I will only clean up the casting flaws and make a smooth transitions on the port floor. Other then that I don't touch it! If you flatten the short side curve you will only hurt flow. The long side radious is less criticle to velocity and more criticle to high valve lift flow. The only reason I can see to deepen the pocket would be if it was the smallest point in the port and to open it up to match the valve and to lessen the restriction. Again probably to fix a less then ideal port. A better way to fix the problem would be to widen the port to one side making the port larger and aid swirl. But again this is an imperfect world and water passages always try to take up the same space as your ideal port wants! LOL

Hope that helps some

[This message has been edited by SundanceKid (edited 04-19-2002).]

IP: Logged

Daniel Jones
Gearhead

Posts: 898
From: St. Louis, MO
Registered: Aug 99

posted 04-19-2002 04:53 PM     Click Here to See the Profile for Daniel Jones   Click Here to Email Daniel Jones     Edit/Delete Message   Reply w/Quote
You might want to check out Vizard's article on porting the Windsor Jr's that was in one of the recent Mustang magazines. Forget which one but it was within the last couple of months.

Dan Jones

IP: Logged

All times are ET (US)

next newest topic | next oldest topic

Administrative Options: Close Topic | Archive/Move | Delete Topic
Post New Topic  Post A Reply
Hop to:

Contact Us | Mustangsandmore Front Page

Copyright 2005, Steve LaRiviere. All Rights Reserved.


Ultimate Bulletin Board 5.47d

Amazon Honor System Click Here to Pay Learn More

[Build a free Mustangsandmore.ws Home Page!]

[Posting Pictures]

[About M&M][Acronyms][Calendar][Chat][Classifieds] [Members' Pics]

[M&M Conventions] [M&M Mug Shots]

[ Mustangsandmore.com Bookstore] [ Smokin' Fords] [Tech Articles]