LS4 Performance Grand Prix GXP | Monte Carlo SS | Impala SS | LaCrosse Super

Thorley Header Project Update

Thread Tools
 
Search this Thread
 
Old Mar 24, 2010 | 06:51 PM
  #901  
DavidGXP's Avatar
12 Second Club
iTrader: (14)
 
Joined: Jun 2007
Posts: 2,563
Likes: 0
From: Renton, WA
Default

You "all" worry way to much just put the headers on all ready! They are warranted! Mine will be going in this weekend and I don't think the install will be all that hard. The instructions even give us a tool list! I'm going to use a exhaust clamp at the collector and have a shop weld up the cat and if that don't work then I'll install a flex pipe and have an exhaust shop install my cat.
Reply
Old Mar 24, 2010 | 06:53 PM
  #902  
DavidGXP's Avatar
12 Second Club
iTrader: (14)
 
Joined: Jun 2007
Posts: 2,563
Likes: 0
From: Renton, WA
Default

I have a Hogan 3" down pipe and am wondering if the collector will fit over the Hogan pipe? I also wonder if the my cat is at the right angle since I had a exhaust shop weld in a 3" cat outlet. Now I'm worrying!!!! During the header install might be a good time to install so E3 plugs there probably a wast of money but I'll give them a shot.
Reply
Old Mar 24, 2010 | 07:00 PM
  #903  
williamGT's Avatar
TECH Fanatic
iTrader: (5)
 
Joined: Jul 2008
Posts: 1,467
Likes: 0
From: Yellowknife NT Canada
Default

I'm getting mine installed next week now (wednesday, thursday or friday) is the Flex pipe needed though? will the engine flex alot?
Reply
Old Mar 24, 2010 | 07:04 PM
  #904  
Mels SS's Avatar
TECH Junkie
iTrader: (1)
 
Joined: Jun 2007
Posts: 3,159
Likes: 0
From: New Orleans La
Default

There be headers here
Reply
Old Mar 24, 2010 | 07:08 PM
  #905  
Mels SS's Avatar
TECH Junkie
iTrader: (1)
 
Joined: Jun 2007
Posts: 3,159
Likes: 0
From: New Orleans La
Default

If you have the dogbone I have the motor doesn't move at all
http://www.3800performance.com/Merch...roduct_Count=4
Reply
Old Mar 24, 2010 | 07:35 PM
  #906  
ImpSS07's Avatar
TECH Resident
iTrader: (3)
 
Joined: Feb 2009
Posts: 933
Likes: 0
From: Houston, Tx
Default

I got mine in today!!! Damn mailman just left them on the doorstep of my "shady" apartments, *******!!!

Reply
Old Mar 24, 2010 | 07:36 PM
  #907  
williamGT's Avatar
TECH Fanatic
iTrader: (5)
 
Joined: Jul 2008
Posts: 1,467
Likes: 0
From: Yellowknife NT Canada
Default

I don't think the flex pipe will work, no room.
Reply
Old Mar 24, 2010 | 07:44 PM
  #908  
07carlocrusader's Avatar
TECH Enthusiast
 
Joined: Jul 2008
Posts: 703
Likes: 0
From: Atlanta Georgia USA
Default

Originally Posted by williamGT
I'm getting mine installed next week now (wednesday, thursday or friday) is the Flex pipe needed though? will the engine flex alot?
ohh!!! Now I see what ya mean William!! I don't know, good question! Hopefully not!

Congrads Mel!! And maybe I'll order those dogbones(well dogbone) to ensure no flex issues!
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

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

 Verdad Gallardo
story-1

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

 Pouria Savadkouei
story-2

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

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo
Old Mar 24, 2010 | 07:55 PM
  #909  
williamGT's Avatar
TECH Fanatic
iTrader: (5)
 
Joined: Jul 2008
Posts: 1,467
Likes: 0
From: Yellowknife NT Canada
Default

Originally Posted by 07carlocrusader
ohh!!! Now I see what ya mean William!! I don't know, good question! Hopefully not!

Congrads Mel!! And maybe I'll order those dogbones(well dogbone) to ensure no flex issues!
Ya, I'm going to order 1 dogbone tomorrow.
Reply
Old Mar 24, 2010 | 08:09 PM
  #910  
williamGT's Avatar
TECH Fanatic
iTrader: (5)
 
Joined: Jul 2008
Posts: 1,467
Likes: 0
From: Yellowknife NT Canada
Default

Originally Posted by Mels SS
If you have the dogbone I have the motor doesn't move at all
http://www.3800performance.com/Merch...roduct_Count=4
Did you get the round msp poly mounts?
Reply
Old Mar 24, 2010 | 08:40 PM
  #911  
TiredGXP's Avatar
TECH Enthusiast
iTrader: (2)
 
Joined: Dec 2007
Posts: 677
Likes: 0
From: Sherwood Park, AB
Default

I'd prefer to put a flex in the downpipe. Poly dogbone sounds like a good idea too.


Oh, headers came today.

Reply
Old Mar 24, 2010 | 08:56 PM
  #912  
Mels SS's Avatar
TECH Junkie
iTrader: (1)
 
Joined: Jun 2007
Posts: 3,159
Likes: 0
From: New Orleans La
Default

Originally Posted by williamGT
Did you get the round msp poly mounts?
Yes sir and this
http://www.3800performance.com/Merch...ct_Code=MSP-MM
Reply
Old Mar 24, 2010 | 08:58 PM
  #913  
Mels SS's Avatar
TECH Junkie
iTrader: (1)
 
Joined: Jun 2007
Posts: 3,159
Likes: 0
From: New Orleans La
Default

So what exactly needs welding? and where I have the stock down pipe and cat Please explain.
Reply
Old Mar 24, 2010 | 09:16 PM
  #914  
BuickRacer's Avatar
Thread Starter
Staging Lane
 
Joined: Jan 2009
Posts: 87
Likes: 0
From: Orange County, CA
Default

Originally Posted by Mels SS
So what exactly needs welding? and where I have the stock down pipe and cat Please explain.
The secondary collector (see photo at the bottom of page 45) gets welded to the downpipe...which you have to cut.
Reply
Old Mar 24, 2010 | 09:39 PM
  #915  
mixerda's Avatar
On The Tree
 
Joined: Aug 2007
Posts: 130
Likes: 0
From: Austin Tx.
Default

just run it open, you and your neighbors will get used to it after a while

consider it a weight saver since you won't be needing the rest of the exhaust hahaha
Reply
Old Mar 24, 2010 | 10:10 PM
  #916  
AlabamaGuy's Avatar
TECH Addict
iTrader: (5)
 
Joined: Jun 2009
Posts: 2,802
Likes: 0
Default

I'm probably going to have mine flanged. I did buy a 6" piece of 3" flex pipe, though.

Good thing I've got a good group of friends to help me put it on. Just have to feed them!
Reply
Old Mar 24, 2010 | 10:21 PM
  #917  
07carlocrusader's Avatar
TECH Enthusiast
 
Joined: Jul 2008
Posts: 703
Likes: 0
From: Atlanta Georgia USA
Default

Originally Posted by Mels SS
So what exactly needs welding? and where I have the stock down pipe and cat Please explain.
The only spot is here:


Everything else is bolt on!! If you want to do most of the work and you have patience, do it!! And bring it to a nearby shop and get that part welded! Mel, you actually going to cut pretty much ALL your downpipe!! All the way to about a 1/2 right before the cat!! Why? Cause if you notice on your/our rear headers, they begin to slope downward and keeps going with the collector until the "welding" area. So this eliminates a necessity down pipe.......



Or you can just leave it open, like mixerda says!! Haha!!
Reply
Old Mar 24, 2010 | 11:19 PM
  #918  
neilownz's Avatar
TECH Fanatic
 
Joined: May 2008
Posts: 1,769
Likes: 0
From: Fargo, ND
Default

It would probably be cheaper to do most of it, tow the car to the shop, and have them finish it. Hell if it's not super loud I would drive it there and just keep the rpms low.
Reply
Old Mar 24, 2010 | 11:33 PM
  #919  
AlabamaGuy's Avatar
TECH Addict
iTrader: (5)
 
Joined: Jun 2009
Posts: 2,802
Likes: 0
Default

Originally Posted by neilownz
It would probably be cheaper to do most of it, tow the car to the shop, and have them finish it. Hell if it's not super loud I would drive it there and just keep the rpms low.
It'd probably be a little bit louder than a open catless DP.
Reply
Old Mar 25, 2010 | 12:43 AM
  #920  
07carlocrusader's Avatar
TECH Enthusiast
 
Joined: Jul 2008
Posts: 703
Likes: 0
From: Atlanta Georgia USA
Default

Originally Posted by neilownz
It would probably be cheaper to do most of it, tow the car to the shop, and have them finish it. Hell if it's not super loud I would drive it there and just keep the rpms low.
Thats exactly what I'm going to do!!
Reply



All times are GMT -5. The time now is 09:50 AM.

story-0
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-1
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-2
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-3
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-4
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
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE