Covering holes on heads

Thread Tools
 
Search this Thread
 
Old November 2nd, 2007, 07:24 PM
  #1  
Registered User
Thread Starter
 
olds307owner's Avatar
 
Join Date: Apr 2007
Location: Roma, TX
Posts: 23
Covering holes on heads

hey everyone, well, I was thinking of doing a little something for my cars performance this weekend, and Ive heard that you can remove the tubes in the heads by the exhaust manifolds. Ive heard that you remove them and put bolts to cover the holes where the tubes were. Does anyone here know if there are any adverse effects to doing this? Also, is removing the tubes and covering the holes all youre supposed to do or is there anything else?
olds307owner is offline  
Old November 2nd, 2007, 10:11 PM
  #2  
Registered User
 
Redog's Avatar
 
Join Date: Aug 2006
Location: Far Northeast Philadelphia, PA
Posts: 3,145
Car will fail emissions moreso than it would without doing this, and most likely bring on a check engine light.

Don't forget to plug up the tube from the cat too
Redog is offline  
Old November 3rd, 2007, 06:35 AM
  #3  
Old(s) Fart
 
joe_padavano's Avatar
 
Join Date: Mar 2007
Location: Northern VA
Posts: 47,661
Originally Posted by olds307owner
hey everyone, well, I was thinking of doing a little something for my cars performance this weekend, and Ive heard that you can remove the tubes in the heads by the exhaust manifolds. Ive heard that you remove them and put bolts to cover the holes where the tubes were. Does anyone here know if there are any adverse effects to doing this? Also, is removing the tubes and covering the holes all youre supposed to do or is there anything else?
Removing the A.I.R. tubes from the exhaust ports on a 307 will produce exactly ZERO performance improvement - but you'll definitely waste a weekend and probably snap off at least one of the A.I.R. manifold nuts in the process.

First, there are NO easy, five minute, 20 HP improvements you can make. The entire engine is designed to work as a system and everything has to be matched to see significant benefits. The goal is to move more air in and out of the engine. Simply removing the tubes does exactly NOTHING unless you pull the heads, grind down the bosses inside the exhaust ports, upgrade to headers, and run a true dual exhaust system. Of course, at that point you need to upgrade the intake and change the programming on the timing curve. Then a new cam is in order, etc, etc.

The good news is that removing the A.I.R. tubes only will NOT trigger a check engine light...

Last edited by joe_padavano; November 3rd, 2007 at 06:37 AM. Reason: spelling
joe_padavano is offline  
Old November 3rd, 2007, 06:46 AM
  #4  
Moderator
 
Olds64's Avatar
 
Join Date: Jul 2007
Location: Edmond, OK
Posts: 16,142
I believe Joe is correct. removing the AIR tubes from the exhaust won't cause a check engine light. Air is injected into the exhaust manifold to lower HC emissions on older cars. The extra O2 helps burn the unburned fuel or HC.
Olds64 is offline  
Old November 3rd, 2007, 11:08 AM
  #5  
Registered User
Thread Starter
 
olds307owner's Avatar
 
Join Date: Apr 2007
Location: Roma, TX
Posts: 23
If I aint going to feel any improvement, then I guess I wont do it. As for the emissions and check engine light I dont really care because my emissions arent checked and my check engine light has been on since 98 when my dad got the car. Thanks for your input.
olds307owner is offline  
Old November 3rd, 2007, 11:14 AM
  #6  
Seasoned beater pilot.
 
J-(Chicago)'s Avatar
 
Join Date: Jan 2007
Location: Chicago
Posts: 5,468
A lil' electric tape will fix your check engine light right up.
J-(Chicago) is offline  
Old November 3rd, 2007, 12:32 PM
  #7  
Old(s) Fart
 
joe_padavano's Avatar
 
Join Date: Mar 2007
Location: Northern VA
Posts: 47,661
Originally Posted by Olds64
I believe Joe is correct. removing the AIR tubes from the exhaust won't cause a check engine light. Air is injected into the exhaust manifold to lower HC emissions on older cars. The extra O2 helps burn the unburned fuel or HC.
Just to add to this a little, the A.I.R. injection into the heads is only functional when the engine is cold, before the O2 sensor heats up. After the O2 sensor comes on line (about 2-3 minutes after startup) the A.I.R. system switches all air to the converter tap to prevent overheating the cat. The only computer interface to the system is commanding the solenoids that switch the air from manifolds to cat to dump.
joe_padavano is offline  
Old November 3rd, 2007, 03:00 PM
  #8  
Registered User
 
Redog's Avatar
 
Join Date: Aug 2006
Location: Far Northeast Philadelphia, PA
Posts: 3,145
Originally Posted by olds307owner
If I aint going to feel any improvement, then I guess I wont do it. As for the emissions and check engine light I dont really care because my emissions arent checked and my check engine light has been on since 98 when my dad got the car. Thanks for your input.

Pull the bulb out then, I did it to mine when I swapped in the 350. No CPU, Check engine light.

It's easy
Redog is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Macadoo
Interior/Upholstery
11
May 15th, 2015 07:17 PM
joepenoso
Care and Appearance
3
October 21st, 2013 08:17 PM
coldfire
Small Blocks
5
July 19th, 2013 08:20 AM
geckonz08
Big Blocks
3
November 25th, 2009 09:01 AM
65cutty
Small Blocks
7
November 11th, 2009 03:48 AM



Quick Reply: Covering holes on heads



All times are GMT -7. The time now is 03:16 AM.