Pelican Parts
Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   Pelican Parts Forums > Porsche Forums > 911 Engine Rebuilding Forum


Reply
 
LinkBack Thread Tools Rate Thread
Author
Thread Post New Thread    Reply
Registered
 
fastfredracing's Avatar
 
Join Date: Jul 2003
Location: Valencia Pa.
Posts: 8,859
Assessing valve guide wear.

I am in the process of checking my valve guides. I borrowed a real nice inside bore gauge from a machinist buddy, I have measured 4 out of 6 heads, and all of my valve to guide clearances fall into the .0035-.0040 range. The specs I have are Intake= .0011-.0059, and Exhaust .0019-.0078.
I am sort of looking for a go- no go answer here. I have no problem spending for a valve job, but these heads were definately done at some point recently, the car has less than 80,000 miles, and the leakdown #s were pretty good when I checked it before teardown.

__________________
No left turn un stoned
Old 06-12-2011, 01:43 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #1 (permalink)
Registered
 
Join Date: Oct 2008
Location: Nash County, NC.
Posts: 8,502
Take them to the shop and tell the machinist to change guides as necessary. I leave the judgement to him because he recognizes the wear and spec.
I never have a problem with his decision.
Bruce
Old 06-12-2011, 04:15 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #2 (permalink)
abit off center
 
cgarr's Avatar
 
Join Date: Feb 2002
Location: At the Airport Kentwood, MI
Posts: 7,311
Garage
Send a message via Yahoo to cgarr
The problem is they become oval in shape, side to side may be fine but front to back may not? And they usually open up in the port area which causes exhaust to escape into the valve stem
__________________
______________________
Craig
G2Performance
Twinplug, head work, case savers, rockers arms, etc.

Last edited by cgarr; 06-12-2011 at 05:08 PM..
Old 06-12-2011, 05:06 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #3 (permalink)
Registered
 
Join Date: Jan 2006
Location: Louisville, KY
Posts: 915
Quote:
Originally Posted by Flat6pac View Post
Take them to the shop and tell the machinist to change guides as necessary. I leave the judgement to him because he recognizes the wear and spec.
I never have a problem with his decision.
Bruce
I agree. Let the machinist buddy decide. That's his forte.
__________________
Gone
92 C2
82 Euro SC race car
993 C4S 3.8
84 Euro Carrera
Old 06-12-2011, 09:35 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #4 (permalink)
Air Medal or two
 
afterburn 549's Avatar
 
Join Date: Jul 2003
Location: cross roads
Posts: 14,079
I have done a "few " valve jobs..they are not out of the way that hard to do...if you want to purchase the equipment..I am ANILE about proper fits in the valve to seat area..but 1st the guide has to locate the valve to the seat...most every time would be a good thing LOL
SO, once you mess with the guides you have to redo your seats....
back to your stem clearance..I have found that a experianced feel is quicker and better then all the dials in the world for this application

__________________
D troop 3/5 Air Cav,( Bastard CAV) and 162 Assult Helicopter Co- (Vultures) South of Saigon, U Minh Forest, Delta, and all parts in between
Old 06-19-2011, 03:19 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #5 (permalink)
Reply


 


All times are GMT -8. The time now is 11:20 AM.


 
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2025 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page
 

DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.