Generation III External Engine LS1 | LS6 | Bolt-Ons | Intakes | Exhaust | Ignition | Accessories
Sponsored by:
Sponsored by:

Header flanges shrunk

Thread Tools
 
Search this Thread
 
Old May 1, 2008 | 07:05 PM
  #1  
NoGamesLS1's Avatar
Thread Starter
TECH Resident
iTrader: (16)
 
Joined: Jul 2005
Posts: 800
Likes: 0
Angry Header flanges shrunk

My car has been down for about 6 months. I few weeks ago I put on some new heads. Came time to bolt up the headers and the bolt holes did not like up. I thought the problem was with the new head so I removed the headers and tried to bolt it up to the old head. The bolt holes do no line up. They are off by about 1.5mm. I can get in the 2 middle bolts and the 2 to either side, but not all 6 at the same time. I had no problems when they were removed a couple months ago. They are kooks 1 7/8. Any ideas what could have caused this?
Thanks
Reply
Old May 1, 2008 | 07:27 PM
  #2  
95GreenZ28's Avatar
TECH Addict
iTrader: (70)
 
Joined: Apr 2007
Posts: 2,155
Likes: 0
From: Amarillo, Texas
Default

I had a similar problem. I just had to barely start the bolts and then tighten them from there.
Reply
Old May 1, 2008 | 08:54 PM
  #3  
primer84z's Avatar
TECH Regular
15 Year Member
iTrader: (7)
 
Joined: Jan 2008
Posts: 426
Likes: 0
Default

^ there should be a little wiggle room in each bolt hole on the flange. I had this happen before and I was about to throw a header through the windshield. I had to just start each one a little and make it line up before tightening them down.
Reply
Old May 1, 2008 | 09:27 PM
  #4  
NoGamesLS1's Avatar
Thread Starter
TECH Resident
iTrader: (16)
 
Joined: Jul 2005
Posts: 800
Likes: 0
Default

They are not tightened down. They are in just a couple threads. It is not a problem of improper installation.
Reply
Old May 1, 2008 | 11:02 PM
  #5  
massls1guy's Avatar
TECH Fanatic
iTrader: (9)
 
Joined: Nov 2005
Posts: 1,311
Likes: 0
From: Mass
Default

I would take a dremel and widen the holes in the header. You don't want to stress the bolts going into your aluminum head. I turned all my header bolts in by hand almost all the way before putting a wrench on them. Make sure you put some anti-sieze on those bolts and never force them.
Reply
Old May 2, 2008 | 12:03 PM
  #6  
GuitsBoy's Avatar
TECH Senior Member
iTrader: (4)
 
Joined: Apr 2003
Posts: 6,249
Likes: 3
From: Long Island, NY
Default

Originally Posted by massls1guy
I would take a dremel and widen the holes in the header. You don't want to stress the bolts going into your aluminum head. I turned all my header bolts in by hand almost all the way before putting a wrench on them. Make sure you put some anti-sieze on those bolts and never force them.
Good post. Id suggest the same.
Reply
Old May 2, 2008 | 12:15 PM
  #7  
Grimes's Avatar
TECH Addict
iTrader: (3)
 
Joined: Mar 2003
Posts: 2,636
Likes: 2
From: Northern NJ
Default

+1 Dremel time. Take a little bit off each hole, not a lot out of one, btw.
Reply
Old May 2, 2008 | 02:05 PM
  #8  
1999T/A's Avatar
TECH Apprentice
iTrader: (4)
 
Joined: May 2004
Posts: 300
Likes: 0
From: Fuquay Varina , NC
Default

Anti - seize on header bolts ???? I did that ONCE . After losing header bolts going down the road and then I had to forever tighten them at least once a month . screw that ! LOL !!!

To each his own , but aint no way im doin that . I can see putting anti-sieze on your spark plugs though . BTW, I have never had one problem with stripping bolt holes or header bolt loosening or losing bolts. They always come right out without anti-seize . Maybe im just lucky IDK .
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

10 Reasons Daily Driving a Swap Project SUCKS! (& 1 Reason to Do It Anyway)

 Michael S. Palmer
story-1

6 Gifts Neither Your Dad Nor Grad Will Shove Into the 'Trinket Drawer'

 Brett Foote
story-2

Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

 Pouria Savadkouei
story-3

Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

 Verdad Gallardo
story-4

7 Most Reliable High-Performance Engines GM Has Ever Built

 Verdad Gallardo
story-5

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-6

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-7

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-8

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-9

Top 10 Most Powerful Chevy Trucks Ever Made!

 
Old May 2, 2008 | 03:13 PM
  #9  
Hilton's Avatar
Tough Mudder
20 Year Member
iTrader: (36)
 
Joined: Aug 2004
Posts: 992
Likes: 0
From: Shreveport, LA
Default

We've drilled out header flanges before too. I put either anti seize or thread locker on every bolt I turn. Went with the locking "Stage 8" header bolts and haven't had any problems.
Reply
Old May 2, 2008 | 03:30 PM
  #10  
1999T/A's Avatar
TECH Apprentice
iTrader: (4)
 
Joined: May 2004
Posts: 300
Likes: 0
From: Fuquay Varina , NC
Default

I agree with the thread locker . . . IDK maybe I used too much anti-sieze , but I will never use it again because of my bad experience . As always YMMV . . . .
Reply




All times are GMT -5. The time now is 12:25 PM.

story-0
10 Reasons Daily Driving a Swap Project SUCKS! (& 1 Reason to Do It Anyway)

Slideshow: 10 reasons daily-driving a swap project might not be for you. Or is it?

By Michael S. Palmer | 2026-06-17 09:39:05


VIEW MORE
story-1
6 Gifts Neither Your Dad Nor Grad Will Shove Into the 'Trinket Drawer'

Don't get dad new socks or a grill brush this year.

By Brett Foote | 2026-06-09 14:55:56


VIEW MORE
story-2
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

Slideshow: We take a close look at the ONE and Artidiag 800BT2 diagnostic tools from Topdon and the reasons to buy one over the other.

By Pouria Savadkouei | 2026-06-18 10:26:23


VIEW MORE
story-3
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

Slideshow: The controversial Ferrari F6 swaps its original flat-12 for a Corvette Z06-derived LT4 V8 and sends power to four rear wheels through a custom-built drivetrain.

By Verdad Gallardo | 2026-05-26 18:23:54


VIEW MORE
story-4
7 Most Reliable High-Performance Engines GM Has Ever Built

Slideshow:These GM engines didn't just make huge power, they survived abuse, boost, track days, and six-digit mileage with a reputation for refusing to quit.

By Verdad Gallardo | 2026-05-21 16:45:27


VIEW MORE
story-5
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-6
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-7
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-8
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-9
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE