What Porting IS

Moderator: Mod Squad

Hot 6t Falcon
VIP Member
Posts: 458
Joined: Fri Nov 08, 2002 10:16 pm
Location: Grand Forks, ND
Contact:

What Porting IS

Post #1 by Hot 6t Falcon » Thu Mar 06, 2003 3:57 pm

Dennis Schjeldahl, (say Shell-doll)
Co-Author of The Ford Falcon Performance Handbook
http://www.falcon6handbook.com

User avatar
CoupeBoy
VIP Member
Posts: 3438
Joined: Fri Nov 08, 2002 12:17 am
Location: Fargo, ND
Contact:

head porting

Post #2 by CoupeBoy » Thu Mar 06, 2003 4:07 pm

Thanks Dennis,

I have always wondered, what if a person got to crazy around the valve guide? Could you remove too much in this area that it would weaken it, or that the valve could have bindage during its motion? Or could grinding it up higher gain any flow?

And I had forgot all about the sharp edges caused by milling :oops:

When unshrouding the valves, if a larger combustion chamber is desired (turbo application possibly) can you lay the edge back and extend it all the way to the edge of the opening in a head gasket?

-ron

Hot 6t Falcon
VIP Member
Posts: 458
Joined: Fri Nov 08, 2002 10:16 pm
Location: Grand Forks, ND
Contact:

To Coupeboy

Post #3 by Hot 6t Falcon » Thu Mar 06, 2003 4:28 pm

The Ford SIX has a pretty long valve guide and it's unlikely that grinding it away in the bowl area would affect the valve's movement. However, tapering it is probably sufficient.

Yes, you can unshroud all the way to the head gasket line.

I am asking to get this added as a "sticky" so please start a new topic if you have more questions.

Good Luck
Dennis Schjeldahl, (say Shell-doll)
Co-Author of The Ford Falcon Performance Handbook
http://www.falcon6handbook.com

pumbaplus

Post #4 by pumbaplus » Mon Apr 19, 2004 5:17 am

hi guys
how do i get pics up of the port jobs ive done i think their the goods ....

ive dethrouded around the guides but with a ridge leadiing up to the guide...
splits the airstream into two,

exhaust ports are more difficult on my ohc, anyone got any sugestions???

Fabricator

Post #5 by Fabricator » Thu Dec 16, 2004 11:36 am

Howdy fellas,


We had too much time on our hands one evening and dropped the saw through a damaged Carb'd 300 head. One pic is intake and the other is exaust, but I don't recall anymore. All I know is that they are great bookends :lol:

Image Image

Hope this is mildy useful...

Fabricator

User avatar
StrangeRanger
VIP Member
Posts: 5789
Joined: Fri Nov 08, 2002 5:54 pm
Location: Copley, OH

Post #6 by StrangeRanger » Thu Dec 16, 2004 12:24 pm

Fabricator wrote:Hope this is mildy useful...

Sorry, it goes WAY beyond "mildly" useful :wink:

User avatar
Asa
Registered User
Posts: 4318
Joined: Thu Nov 28, 2002 2:40 pm
Location: Tampa, Tallahassee, Hangin out in some Florida woods somewhere
Contact:

Post #7 by Asa » Thu Dec 16, 2004 12:27 pm

i'm pretty sure that'll help a good amount when i drop off my head to get it worked
seriously, thanks for that
Right and Wrong are just words, what matters is what you do

Susie - a work in progress
Clyde - ya mule!

User avatar
WhitePony
Registered User
Posts: 429
Joined: Mon Feb 07, 2005 11:38 pm
Location: Moore, Oklahoma

Post #8 by WhitePony » Wed Feb 09, 2005 10:03 am

One question Dennis. In the write-up you say that you can increase the size of the combustion chamber while you unshroud the valve. Won't changing the physical size of the combustion chamber alter the compression ratio? After the porting is complete would you need to mill the head down to maintain CR?

Thanks
Kris
The other day I went to court for a parking ticket......... I plead insanity. I asked the judge "Who in their right mind would park in the passing lane?"

65 Mustang Convertible, Currently undergoing "Open Hood Surgery"
My other toy 24' Crownline with a custom 550HP 502

Hot 6t Falcon
VIP Member
Posts: 458
Joined: Fri Nov 08, 2002 10:16 pm
Location: Grand Forks, ND
Contact:

Mostly Yes

Post #9 by Hot 6t Falcon » Wed Feb 09, 2005 11:44 am

Yup, unshrouding the valves (and polishing the chamber) lowers the compression.

You could bring the cylinder pressure back up with a flat-top piston, head milling, block milling, or a supercharger. With the supercharger, you won't want much more that an 8:1 compression - depending on the boost.
Dennis Schjeldahl, (say Shell-doll)
Co-Author of The Ford Falcon Performance Handbook
http://www.falcon6handbook.com

User avatar
Stubby
VIP Member
Posts: 911
Joined: Sat Mar 26, 2005 1:11 pm
Location: Carthage, Texas
Contact:

Post #10 by Stubby » Wed Jul 06, 2005 8:00 pm

I would like to Give a little advice for anyone doing port work for the first time. When you start porting the head, pick an area like the exaust bowl area under the seat. It could be the short side radius or the back off the bowl it does not matter, but work this area on all six ports then do another area, again all six ports then move on.

I have seen many first time port jobs and they are usualy pretty good for the first time. The one thing that I almost always see is unbalanced flow. I am sure some of my early port work was the same. Most people seem to work one port to completion at a time and each port recieves a little less or more as you go. Start great and finish tired. One big port and 5 to 7 progressively smaller ports.

If you work one area at a time and finish all six in this area you will be able to duplicate your results more closely. If you get half way thru the port job and decide port work isn't fun anymore it will be balanced better even if it isn't finished.

Sedanman
Registered User
Posts: 159
Joined: Fri Jul 31, 2009 8:01 pm

Re: What Porting IS

Post #11 by Sedanman » Sun Aug 02, 2009 4:05 am

Good advice, stubby - I'm about to take on my first porting/polishing project, and know I don't have enough time to do all of the combustion chambers, valve areas, exhaust manifold, carb opening, etc. Hot 6 T Falcon's comment about all of the different ways to bring compression back up is why I'm hesitant to take on combustion chamber work. My bottom end is good and not going to come apart for new pistons or decking...

Super long post on all of this about to appear :lol:
Thor
Pre-GT Caspian Blue '65 Fastback in family since new, currently under barn car status awaiting restoration.

User avatar
'68falconohio
Registered User
Posts: 443
Joined: Wed Mar 11, 2009 10:48 pm
Location: Marcellus and Utica Money Formations

Re: What Porting IS

Post #12 by '68falconohio » Thu Oct 22, 2009 6:51 pm

'68 Falcon - sold
'99 F-250 Super Duty, '64 Lincoln SA-200 "Redface" - weldin' car
'04 F-350 Super Duty - racecar

Crash5291
Registered User
Posts: 57
Joined: Sun Apr 04, 2010 1:39 pm
Location: Eastern Ontario, Canada

Re: What Porting IS

Post #13 by Crash5291 » Wed Feb 27, 2013 4:21 am

Anyone have copys of the pictures they can repost?

Who is online

Users browsing this forum: No registered users and 1 guest