Tech / General Engine Is your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!
Sponsored by:
Sponsored by: CARiD

Positive Or Umbrella Valve Seal On Exhaust?

Thread Tools
 
Search this Thread
 
Old Feb 22, 2003 | 12:55 PM
  #1  
89Formula305tpi's Avatar
Thread Starter
Junior Member
 
Joined: Feb 2003
Posts: 2
Likes: 0
Positive Or Umbrella Valve Seal On Exhaust?

I have done some searching and haven't found a real definitive answer. Who has positive seals on both the intake and exhaust for several years and has good luck with them?
Is it true that positive seals will starve the exhaust guides for oil?
And I was wondering what kind of seals the LT-1's have because as far as I know they don't have a smoking problem. Do they use all positives?
Thanks
Reply
Old Feb 22, 2003 | 03:39 PM
  #2  
Damon's Avatar
Supreme Member
 
Joined: Sep 1999
Posts: 7,072
Likes: 13
From: Philly, PA
That's a good question. I'll say that I usually use posi seals on the intake and umbrellas on the ehaust for exactly the reason you describe- I don't want any chance of starving the exh guide for oil. It's a combo that has worked well for me. Most oil consumption seems to happen on the intake side anyway since it's under vacuum all the time from the intake port, unlike the exhaust.

However, most aftermarket heads come with posi seals on both intake and exhaust and I don't hear many people complaining about worn out exhaust guides because of it.

LT-1 heads I'm not sure about. I think they have posi seals on both intake and exhaust but remember that the factory can make minute changes to the seals and whatnot that might not be obvious to the naked eye.
Reply
Old Feb 22, 2003 | 05:05 PM
  #3  
ede's Avatar
ede
TGO Supporter
 
Joined: Aug 1999
Posts: 14,811
Likes: 1
From: Jackson County
i use positive seals and o ring seals both, never had a problem and i've stuck them on more than one set of heads. i don't like ot use the umbrella seals.
Reply
Old Feb 22, 2003 | 05:15 PM
  #4  
89Formula305tpi's Avatar
Thread Starter
Junior Member
 
Joined: Feb 2003
Posts: 2
Likes: 0
ede,
How many miles/years have you gone with the positive seals on the exhaust? Have they held up well?
Thanks
Reply
Old Feb 23, 2003 | 06:25 AM
  #5  
ede's Avatar
ede
TGO Supporter
 
Joined: Aug 1999
Posts: 14,811
Likes: 1
From: Jackson County
used them since the 70s on one thing or another. have them on my truck that i just trashed in the snow, 23,000 miles on the rebuild.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
1992 Trans Am
History / Originality
27
May 10, 2023 07:19 PM
db057
Tech / General Engine
4
Aug 22, 2015 08:17 PM
g.l.mos
Camaros for Sale
0
Aug 22, 2015 12:02 AM
Dialed_In
Firebirds for Sale
2
Aug 20, 2015 01:45 PM
86White_T/A305
LTX and LSX
0
Aug 17, 2015 12:16 AM




All times are GMT -5. The time now is 03:04 PM.