Modifications - Performance Discuss aftermarket and DIY performance modifications

Porting cylinder heads

Old 07-23-2010, 11:42 AM
  #1  
Senior Member
SuperSport
Thread Starter
 
Join Date: Mar 2010
Location: Asheville, North Carolina
Posts: 886
1971allchaos is on a distinguished road
Porting cylinder heads

You fine crew, Is there any information on this forum "ON or who will port and polish a set of cylinder heads?
1971allchaos is offline  
Old 07-23-2010, 12:38 PM
  #2  
Banned
MotoGP
 
Join Date: Aug 2007
Location: Lake View Terrace, CA
Posts: 5,942
8541Hawk will become famous soon enough
Search really is your friend...... Sorry Tweety, you're getting slow these days.....lol

But as I happen to have just happened to have looked up the info myself..... here is what you want to do.....

"For the street, the port work should focus on a few things. Do not make major changes to the port area, work on blending the bowls, slight flattening of the port floor around the short radius of each port, matching the carb manifold spigots, and to a good 3 angle valve job. The valve seats should be moved to the outer perimeter of the valves without going all the way to the edge. Total seat contact width should be about 50% of the overall face area."

As found here:
https://www.superhawkforum.com/forum...0&postcount=19

As to where you have it done that is up to you to find.
8541Hawk is offline  
Old 07-23-2010, 02:07 PM
  #3  
Senior Member
SuperSport
Thread Starter
 
Join Date: Mar 2010
Location: Asheville, North Carolina
Posts: 886
1971allchaos is on a distinguished road
Thank you for the info, I have a couple of spare sets, Yet these stock heads/ low milage are not that easy to come by. Any suggestion or recommendation on a shop, or member that would be more experienced in the operation ?
1971allchaos is offline  
Old 07-28-2010, 12:25 PM
  #4  
Senior Member
Back Marker
 
2whltuner's Avatar
 
Join Date: Jun 2010
Posts: 228
2whltuner is on a distinguished road
Ported and Polished Superhawk Heads

these heads have been ported, polished exhaust port, polished combustion chamber, full radius valve job w/undercut, milled .010" off of the head surface, used with stock valves and Kibblewhite racing springs and moriwaki cams

Porting cylinder heads-img_0708.jpg

Porting cylinder heads-img_0709.jpg

Porting cylinder heads-img_0711.jpg
2whltuner is offline  
Old 07-28-2010, 12:43 PM
  #5  
Banned
MotoGP
 
Join Date: Aug 2007
Location: Lake View Terrace, CA
Posts: 5,942
8541Hawk will become famous soon enough
Originally Posted by 2whltuner View Post
these heads have been ported, polished exhaust port, polished combustion chamber, full radius valve job w/undercut, milled .010" off of the head surface, used with stock valves and Kibblewhite racing springs and moriwaki cams
While those do look nice, it's not really what you want for a street motor. They should flow well at high RPM (but I do have to wonder why you didn't also install the over sized valves with that much work) I would be concerned with low RPM stumble as you might have issues with fuel pooling do to disturbing the boundary layer.

The specs listed in my previous post are straight from Moriwaki and work very well unless you are building a full race motor. In that case you have no worries about the lower RPM range. But as always YMMV.
8541Hawk is offline  
Old 07-28-2010, 01:02 PM
  #6  
Senior Member
Back Marker
 
2whltuner's Avatar
 
Join Date: Jun 2010
Posts: 228
2whltuner is on a distinguished road
works well from 1500 all the way through my redline of 10,000
2whltuner is offline  
Old 07-29-2010, 08:25 AM
  #7  
Senior Member
SuperBike
 
RCVTR's Avatar
 
Join Date: Dec 2005
Location: South Lake Tahoe, CA, USA
Posts: 1,689
RCVTR is an unknown quantity at this point
That's the first time I've seen a dimpled intake port. I have heard about it and that it flows very well.

Oversized valves are a good idea. And I'm in the 3-angle valve job camp. I like to have some surface area for the valve face contact - more for the exhaust valves, becuase the valve spends most of it's time closed and the valve contact with the seat is critical for keeping the valves cool.

Otherwise, it looks very good.
RCVTR is offline  
Old 07-29-2010, 11:34 AM
  #8  
Senior Member
Back Marker
 
2whltuner's Avatar
 
Join Date: Jun 2010
Posts: 228
2whltuner is on a distinguished road
I've held off on the oversize valves for the next stage
2whltuner is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
mikstr
Modifications - Performance
3
01-06-2014 11:07 AM
chickenstrip
Classifieds
0
04-18-2009 10:40 AM
driven
Classifieds
12
12-07-2008 05:09 AM
bluesman
Technical Discussion
2
01-31-2006 04:45 PM
v2weapon
Technical Discussion
3
08-01-2005 09:05 AM


Thread Tools
Search this Thread
Quick Reply: Porting cylinder heads


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.