hardened seat question - 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 08-01-2003, 06:52 PM
Member
 
Join Date: Nov 2002
Location: FL
Posts: 43
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
hardened seat question

how goes it board?i was reading up on head work and what i read was that you only have to put hardened seats on the exhaust valve.i always assumed you put it on all valves.why is this?my cam specs are...

Duration Adv. 262in. 270ex
@.50" is 218in 224ex
lift .493in 500ex
lobe sep 110
Comp Cams Xtreme262
would the resurfaced iron seat handle this for the intake or does it need hardened seats also?
its a set of 1971 351 windsor heads and they are going on the 71 windsor.

Thanks for any help.

Blag

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 08-01-2003, 07:44 PM
NorthStar's Avatar
Member
 
Last photo:
Join Date: Feb 2003
Location: Minnesota
Age: 51
Posts: 847
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
The intake side doesnt get anywhere near as hot as exhaust so no hard seats required on intake valves.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 08-02-2003, 12:12 PM
Max Keith's Avatar
Member
 
Last photo:
Join Date: Jul 2003
Location: Fort Madison,Iowa
Age: 66
Posts: 2,391
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
hardened valve seats

The reason for the hardened valve seats is that tetraethyl lead used as an additive used to keep the valve seats lubricated as well as up the octane. Since lead is no longer used, the seats tend to erode, hence the hardened valve seats on the exhaust. heat was also a major factor on this.
Your cam etc is not relevant to the valve seats and it will handle the higher lift etc. My recommendation is that you do a pocket porting job on the heads. This will garner you as much or more hp than does the cam you are putting in. A good pocket job is worth 35-50 hp, depending on the heads, and it effects your breathing under the cam curve greatly. I had the oportunity, to have a 302 dynoed one time, that I had built for my pickup. I was running early 351 W valves in it and an early 351 cam. .416/.416 lift 198/198 duration, with a factory cast iron 4v intake from a 289, 1 1/2 inch primary headers, and 9.5:1 comp. The second run was done after I pocket ported the heads and I gained 37 hp for my work.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 08-02-2003, 03:04 PM
Member
 
Join Date: Nov 2002
Location: FL
Posts: 43
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
yeah i just finished porting the heads the other day ground down the exhaust hump opened it up a little,port matched intake and smoothed out the bowls.it was a real tedious job i hope it gets me that kind of gain well thanks for helping me guys.

Blag
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 07:04 AM.


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.