swirl polished valves, why??? - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 09-23-2003, 09:31 AM
New Member
 
Join Date: Sep 2003
Posts: 29
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
swirl polished valves, why???

Can any one tell me what is the purpose of swirl polishing Valves?
Should the swirls be the same for each Valve, or swirl to suit the way the port is entering the combustion chamber?
Should the Exhaust valve be swirl polished?

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 09-23-2003, 11:18 AM
302 Z28's Avatar  
Last photo:
Join Date: May 2003
Location: North Texas
Posts: 10,839
Wiki Edits: 0

Thanks: 1
Thanked 86 Times in 73 Posts
If you have ever seen the backside of a valve, with it's sharp edge and other impediments to flow you will see how swirl polishing improves flow. I do not think it matters which direction the swirl is.

Vince
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 09-23-2003, 11:48 AM
4 Jaw Chuck's Avatar
Hotrodders.com Moderator
 
Last photo:
Join Date: Mar 2002
Location: Manitoba, Canada
Age: 46
Posts: 4,973
Wiki Edits: 0

Thanks: 2
Thanked 89 Times in 72 Posts
Swirl polishing is just the most efficient mass production method to produce a smooth surface on the backside of the valve, personally I turn them on the lathe to cut the backlip. The swirl is just a result of the method and gives no added flow other than sound real nice when you say it.

You can accomplish the same effect with a die grinder and a flat disc against the backside of the valve.
__________________
Outlawed tunes from outlawed pipes
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 09-24-2003, 04:32 AM
Member
 
Last photo:
Join Date: May 2003
Location: Shreveport LA
Age: 64
Posts: 5,103
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
But it sound good, so you gotta pay more.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 09-24-2003, 07:18 AM
SAE Member, ASE Master Cert.
 
Join Date: Aug 2002
Location: Twin Lake, MI
Age: 67
Posts: 332
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
The primary reason for swirl polishing is that it reduces (or eliminates - depending upon who you talk to) the rough surface on the back side of the valve. Rough surface may lead to stress risers and eventually cracks. Therefore, a swirl polished valve is actually stronger that a non-polished valve. The direction of swirl has no bearing at all, just the way the part is manufactured.
A secondary result of swirl polish on the valve is a very slight increase in the flow around the valve. This is a very, very slight increase and probably not even measurable on most flow benches.
As mentioned in an earlier post, most flow improvements relative to the valves themselves are the result of proper (and tedious) blending of the backside of the valve, the seat contact area and the margin (side of the face).
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 09-24-2003, 08:51 AM
New Member
 
Join Date: Sep 2003
Posts: 29
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Thanks for clearing that up for me, I thought it might swirl the mixture into the port but if that were the case the swirl should be matched for each port.
The way i see it the Ex back should be polished right up and the In left a little rough.
When back cutting the valve what works best one 30 deg cut or a series of cuts then blending them all together right around to the back face?
I ended up doing that back cut nearly to the margin leaving a little as i read the valve head expands a little pushing the margin back down towards the port.
Then back cut right around to the back of the valve until it was curved then polished it right up.
Any other areas on the valve that should get some attention?
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 09-24-2003, 11:26 AM
SAE Member, ASE Master Cert.
 
Join Date: Aug 2002
Location: Twin Lake, MI
Age: 67
Posts: 332
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
slr6000,
You might be a little confused by the valve terminology, or maybe I am reading your post wrong. The valve margin is the part of the valve head, between the outer edge of the seat and the face.
I only grind one backcut angle and keep the backcut width the same on all of the valves, then blend it with some emery cloth. There are probably some guys who grind more than one backcut angle on the valve, but I haven't seen any flow improvements in doing so. I also grind a very slight break (about .020" wide and 45 degrees) on the face edge of the valve. This gives a suprising increase in flow, especially then the valves are shrouded.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 10-27-2009, 01:04 AM
techinspector1's Avatar
Senior Curmudgeon
 
Last wiki edit: DynoSim combinations Last photo:
Join Date: Oct 2005
Location: Hemet, California, USA
Age: 72
Posts: 12,946
Wiki Edits: 326

Thanks: 760
Thanked 1,012 Times in 848 Posts
"玉环正祺发动机气门有限公司,玉环正祺动力机械有限公司,发动机气门,气门,汽门 ,进气门,排气门,進氣閥,排氣閥"
I was just gonna say that....
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 10-27-2009, 02:57 AM
S10 Racer's Avatar
http://www.warsprints.com
 

Last journal entry: W.A.R. (Wingless Auto Racing) Sprint Car Racing
Last photo:
Join Date: Nov 2007
Location: At The Dirt Tracks
Age: 55
Posts: 1,888
Wiki Edits: 0

Thanks: 3
Thanked 62 Times in 56 Posts
Quote:
Originally Posted by techinspector1
"玉环正祺发动机气门有限公司,玉环正祺动力机械有限公司,发动机气门,气门,汽门 ,进气门,排气门,進氣閥,排氣閥"
I was just gonna say that....
Took the words right out of my mouth. Does that sentence have the word "break" in it somewhere?
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 10-27-2009, 03:14 AM
techinspector1's Avatar
Senior Curmudgeon
 
Last wiki edit: DynoSim combinations Last photo:
Join Date: Oct 2005
Location: Hemet, California, USA
Age: 72
Posts: 12,946
Wiki Edits: 326

Thanks: 760
Thanked 1,012 Times in 848 Posts
No, but I see "stupid Americans" and "profit" several times.
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 10-27-2009, 06:18 AM
New Member
 
Join Date: Sep 2003
Posts: 29
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
aspirazione,valvole di scarico,エンジン用排気弁,エンジン用排吸気弁,swirl polished valve
yep that clears that up for me, who would have know what goes into designing a vavle for true performance. these guys know there stuff.
Reply With Quote Quick reply to this message
  #12 (permalink)  
Old 10-27-2009, 07:08 AM
6426yy's Avatar
Member
 
Last photo:
Join Date: Nov 2003
Location: Macomb Il.
Age: 35
Posts: 550
Wiki Edits: 0

Thanks: 1
Thanked 0 Times in 0 Posts
What about dimpled valves? Like a golf ball.
Reply With Quote Quick reply to this message
  #13 (permalink)  
Old 10-27-2009, 08:36 AM
Registered User
 
Last photo:
Join Date: Oct 2009
Location: Seattle
Posts: 312
Wiki Edits: 0

Thanks: 0
Thanked 14 Times in 11 Posts
"The way i see it the Ex back should be polished right up "

something about exhaust gas reversion back into the cylinder kills performance, might look pretty but I don't think it's worth the work.

"yep that clears that up for me, who would have know what goes into designing a vavle for true performance."

Ford, hollow stems, sodium filled, tuliped heads, too bad they stopped making them.
Reply With Quote Quick reply to this message
  #14 (permalink)  
Old 10-27-2009, 08:41 AM
techinspector1's Avatar
Senior Curmudgeon
 
Last wiki edit: DynoSim combinations Last photo:
Join Date: Oct 2005
Location: Hemet, California, USA
Age: 72
Posts: 12,946
Wiki Edits: 326

Thanks: 760
Thanked 1,012 Times in 848 Posts
Quote:
Originally Posted by 6426yy
What about dimpled valves? Like a golf ball.
Interesting, but I would think the labor and time involved wouldn't give you a good return. I don't know of anyone who has done this. Might be like tripping over dollars to pick up dimes. Then again, I might be full of it.
Reply With Quote Quick reply to this message
  #15 (permalink)  
Old 10-28-2009, 04:09 PM
6426yy's Avatar
Member
 
Last photo:
Join Date: Nov 2003
Location: Macomb Il.
Age: 35
Posts: 550
Wiki Edits: 0

Thanks: 1
Thanked 0 Times in 0 Posts
http://www.gofastnews.com/board/engi...yno-graph.html

http://www.williamsmotowerx.net/valves.htm

Came across this, something to ponder.
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -6. The time now is 08:51 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.