large valve stem diameter - Hot Rod Forum : Hotrodders Bulletin Board -- 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 05-15-2010, 09:43 AM
9K-sbc's Avatar
Registered User
Last photo:
Join Date: Aug 2009
Location: Southeast, Texas
Posts: 47
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
large valve stem diameter

I recently ran across an sbc with unusually large valve stems, in fact they measure 0.456". Has anyone ever seen valve stems this large? Attached is a photo of the assembly, the roller tip on the rocker is 0.368" and as you can see, it is larger than the stem. Heads are old brodix -8, spring installed height is 2 1/8", spring diameter is 1.560". They were measured with dial calipers, not a micrometer because they are still assembled so give or take .001" or 2 on the stem diameter. Anyone seen this before?
Attached Thumbnails
Click image for larger version

Name:	IMG_0202b.jpg
Views:	180
Size:	37.9 KB
ID:	45662   Click image for larger version

Name:	IMG_0181b.jpg
Views:	174
Size:	38.8 KB
ID:	45663  

Reply With Quote Quick reply to this message
Sponsored Links
  #2 (permalink)  
Old 05-15-2010, 10:41 AM's Avatar
Last photo:
Join Date: May 2002
Location: Holly, michigan
Posts: 8,970
Wiki Edits: 0

Thanks: 85
Thanked 520 Times in 458 Posts
That is a "lash cap" a hardened cap that sets over the valve stem. The valve locks are relieved to clear the cap. These are commonly used on high lift drag race type assemblies.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 05-15-2010, 03:08 PM
ericnova72's Avatar
More for Less Racer
Join Date: Jan 2007
Location: S.W. Lower Michigan
Age: 50
Posts: 13,239
Wiki Edits: 0

Thanks: 140
Thanked 1,753 Times in 1,487 Posts
Like Bob has said, your heads are equipped with lash caps, which are hardened pieces that sit on the valve stem like a bottle cap on a beer bottle. Common racing stuff to either/and/or protect the valve tip, add surface area for the roller tip , or height to keep the rocker body from touching the spring retainer.
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
Fabricating intake manifold. gemini86 Engine 25 10-02-2009 01:10 PM
Valve Stem to Guide Clearance Question y2k600f4 Engine 4 09-04-2009 11:13 AM
Piston notching for valve relief/clearance OHD Engine 9 09-16-2008 10:27 AM
cam question, any truth to this? 406 ss monte Engine 6 03-30-2008 11:28 AM
Valve stem size 87442lover Engine 9 10-30-2003 12:06 PM

All times are GMT -6. The time now is 07:21 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 1999 - 2012. All Rights Reserved.