port and polish - ClassicOldsmobile.com


Reply
 
 
 
LinkBack Thread Tools Search this Thread
Old December 6th, 2009, 08:23 AM   #1  
Registered User
Thread Starter
 
Join Date: Dec 2008
Posts: 173
port and polish

i have 72 350 7a heads that i did a port and polish on. ive been told its best not to polish the intake ports. should i just go over them with a heavier grit sandpaper and do i do the entire port or just the side walls?
dman0712 is offline   Reply With Quote
Old December 6th, 2009, 09:49 AM   #2  
Registered User
 
Join Date: Sep 2009
Location: KY
Posts: 1,489
Inside where it is rough is where the air and fuel mix. If you smooth it out you will ruin the heads. You can make the opening bigger use the intake gasket as a template.
70 cutlass s is offline   Reply With Quote
Old December 6th, 2009, 10:09 AM   #3  
Registered User
 
Join Date: Mar 2008
Posts: 3,366
Just go over them with a coarse sandpaper roll in a drill or die grinder.
Run to Rund is offline   Reply With Quote
Old December 6th, 2009, 10:57 AM   #4  
Registered User
Thread Starter
 
Join Date: Dec 2008
Posts: 173
do i do the entire intake port this way? I thought the air and fuel mixed inside of the intake manifold?
dman0712 is offline   Reply With Quote
Old December 6th, 2009, 02:45 PM   #5  
Registered User
 
Join Date: Mar 2008
Posts: 3,366
not the valve seats of course. Sure air and fuel mix at the carb, but you don't want to encourage fuel to drop out of suspension along the way. Years ago, Mopar max wedge racers found that the rougher castings actually helped power.
Run to Rund is offline   Reply With Quote
Old December 6th, 2009, 04:22 PM   #6  
Registered User
Thread Starter
 
Join Date: Dec 2008
Posts: 173
ok thanks and do you think my valve springs are ok.

Dual Valve Springs I.D. of Outer Dia.: 1.073"
I.D. of Inner Dia.: .697"
Seat load: 121lbs @1.700''
Open load: 337lbs @1.150''
Coil bind: 1.020''
Rate: 392lbs/in
my cam is a hydraulic roller int528 exh 547 duration is int248 exh254. lsa 110. im going to have it ground down a little more though so my duration will be in the 230's
dman0712 is offline   Reply With Quote
Old December 6th, 2009, 06:39 PM   #7  
Registered User
 
Join Date: Nov 2008
Location: Central Fl
Posts: 4,956
You might want to have it ground for more lift as well. If you have good flowing heads lift is horsepower without losing much driveability if any. I have a brand new Erson Hyd Roller for sale if you're interested, 226/234 @ .050, on a 112, .584 lift with 1.6 rockers.

Last edited by cutlassefi; December 6th, 2009 at 06:42 PM.
cutlassefi is offline   Reply With Quote
Old December 6th, 2009, 07:48 PM   #8  
Registered User
Thread Starter
 
Join Date: Dec 2008
Posts: 173
Can my cam be ground for more lift? I know i can reduce the duration.
dman0712 is offline   Reply With Quote
Old December 6th, 2009, 07:58 PM   #9  
Registered User
 
Join Date: Nov 2008
Location: Central Fl
Posts: 4,956
Technically yes but it will reduce the base circle.
cutlassefi is offline   Reply With Quote
Old December 6th, 2009, 08:02 PM   #10  
Registered User
Thread Starter
 
Join Date: Dec 2008
Posts: 173
what is the base circle? should i have it ground down. its a custom ground cam so i cant return it
dman0712 is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Best Chrome Polish I've Ever Used Dan Wirth Care and Appearance 12 February 7th, 2017 04:21 PM
Cut and Polish 35mastr Paint 2 October 28th, 2011 05:23 PM
stainless polish oldsmansugar Care and Appearance 8 March 13th, 2010 02:38 AM
Plastic Polish? Cameo White General Discussion 5 April 10th, 2009 05:31 PM
to port or not to port? 23109 E.O.S. General Questions 17 April 6th, 2009 04:58 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not 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 Off
Pingbacks are Off
Refbacks are Off



All times are GMT -7. The time now is 07:50 PM.


© 2018 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.