head gasket ?? - 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
lost password?   |   register now

LinkBack Thread Tools
  #1 (permalink)  
Old 10-23-2008, 06:51 PM
Registered User
Join Date: Sep 2006
Location: Missouri
Posts: 71
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
head gasket ??

If your slugs are .010 in the hole and presently have .039 head gasket, how thin of a gasket could you go safely before valve to piston clearance? Is it even worth trying to get more compression this way? Thinking of trying .021 or.028 to gain a little. Pistons are 7cc dished valve reliefed. Thank you for your help.

Reply With Quote Quick reply to this message
Sponsored Links
  #2 (permalink)  
Old 10-23-2008, 09:23 PM
DoubleVision's Avatar
Not Considered a Senior Member
Last photo:
Join Date: Oct 2002
Location: Heart Of Dixie
Age: 43
Posts: 10,733
Wiki Edits: 0

Thanks: 19
Thanked 77 Times in 71 Posts
That depends on the cam timing and of course what size cam. If in any doubt do a mock up and check the clearences. If your not running a massive cam there`s not that much worry of piston to valve clearence. as said, it depends on a few varibles.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 10-23-2008, 09:32 PM
techinspector1's Avatar
Last wiki edit: DynoSim combinations Last photo:
Join Date: Oct 2005
Location: Zephyrhills, Florida, USA
Age: 75
Posts: 15,335
Wiki Edits: 326

Thanks: 1,503
Thanked 2,020 Times in 1,560 Posts
You mean valve to piston collision? It's hard to say because of all the variables involved. No two motor alike, particularly the heads. I wouldn't use this method to increase static compression ratio. Well, I might if I needed more static compression ratio to match up with a cam that is too big for the motor, but that should have been figured out when the motor was built. I might also use it to improve squish if my cylinder pressure was such that the motor rattled on the available fuel. The tightest I'd go on squish is 0.035". David Vizard runs em' there.

One full point of compression (for instance 9.0 to 10.0) will increase power 4%. If you're at 0.049" on the squish now, the tightest you could go is another 0.014"..... 0.014" on a 4.100" bore gasket is 3cc's. If you started with a motor that is 10.06:1 for instance, cutting 3cc's out of the equation would yield 10.42:1 and theoretically increase power about 1.3% (5.2 horsepower on a 400 hp motor)

Last edited by techinspector1; 10-23-2008 at 09:45 PM.
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply

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:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Please select your insurance company (Optional)


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

Similar Threads
Thread Thread Starter Forum Replies Last Post
Head Gasket 101 camaro freak Engine 9 08-06-2007 09:39 AM
Choosing correct Head Gasket - HELP! NovaHO Engine 3 05-30-2007 06:39 AM
buy a used engine vs. replace head gasket? andrewpruitt Engine 8 03-21-2005 05:52 PM
Cracked Head or Blown Gasket? '71 rag top Engine 1 12-15-2004 10:08 PM
Head Gasket installation '67Pony Engine 3 07-27-2003 11:33 AM

All times are GMT -6. The time now is 08:28 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.