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

Question about MAC mid-length headers.

Thread Tools
 
Search this Thread
 
Old May 7, 2005 | 12:02 PM
  #1  
SSCoulter's Avatar
Thread Starter
Launching!
iTrader: (4)
 
Joined: Jun 2004
Posts: 203
Likes: 0
From: North Little Rock, Arkansas
Default Question about MAC mid-length headers.

I am buying a set of MAC's and I want to know how they will work with my SLP "Y" pipe and Loudmouth. Will they bolt up to what I have now or will I need to change the y pipe ect.? I want to keep my LM if I can so thanks for the info in advance.
Reply
Old May 7, 2005 | 12:29 PM
  #2  
setxws6's Avatar
TECH Apprentice
 
Joined: Oct 2003
Posts: 396
Likes: 0
From: Lumberton, TX
Default

Nope, the macs use ball flanges while SLPs don't. I hope you got at least coated. I had some uncoated Mac midlengths on my car, and I didn't even have them on for a year and they looked like ****. Bad surface rust. Also, they were't easy getting in. You'll have to take the pass side valve cover off and slowly fit them in from the top. The driver side, you will have to take the motor mount bolt out and jack that side of the engine up a bit to slide them in. It's not too late, sale them and get some nice LT's.
Reply
Old May 7, 2005 | 12:34 PM
  #3  
SSCoulter's Avatar
Thread Starter
Launching!
iTrader: (4)
 
Joined: Jun 2004
Posts: 203
Likes: 0
From: North Little Rock, Arkansas
Default

So I will need a different Y pipe or will I need some custom exhaust work or what? I got the MAC's really cheap so I want to use them I just want to know what I will have to do to make them work with my existing set up. Good friend here owns a exhaust shop so I know I can get that kind of work done if I need to, just need to know if I need some other ORY or catted Y or what.
Reply
Old May 7, 2005 | 12:41 PM
  #4  
USMARINE1108's Avatar
TECH Regular
15 Year Member
iTrader: (2)
 
Joined: Apr 2005
Posts: 490
Likes: 22
From: Beaufort SC
Default

I love my Mac's, if you're planning on lowering your car in the future, keep 'em. Even if you're not planning on it, keep em if you want to. Any exhaust shop should be able to fabricate the SLP Y to Macs. Only problem is, you do want that connection to be able to twist a little bit when your motor revs. But most most people that I have seen over tighten that connection anyway, and have no problem with it. I did a write up of the install, link's here. I pm'd you the link, because it's not on this site. Hope this helps you.
Reply
Old May 7, 2005 | 12:41 PM
  #5  
SSCoulter's Avatar
Thread Starter
Launching!
iTrader: (4)
 
Joined: Jun 2004
Posts: 203
Likes: 0
From: North Little Rock, Arkansas
Default

Originally Posted by USMARINE1108
I love my Mac's, if you're planning on lowering your car in the future, keep 'em. Even if you're not planning on it, keep em if you want to. Any exhaust shop should be able to fabricate the SLP Y to Macs. Only problem is, you do want that connection to be able to twist a little bit when your motor revs. But most most people that I have seen over tighten that connection anyway, and have no problem with it. I did a write up of the install, link's here. I pm'd you the link, because it's not on this site. Hope this helps you.
Thank you!
Reply
Old May 7, 2005 | 01:55 PM
  #6  
1999T/A's Avatar
TECH Apprentice
iTrader: (4)
 
Joined: May 2004
Posts: 300
Likes: 0
From: Fuquay Varina , NC
Default

Macs aren't bad to install at all . I had mine in in about 4 hrs . Easiest mod I have done to my car yet . I jacked my car up and went in from the bottom . They slid in like a dream . I got mine so cheap used that im just gonna stick withem until they fall apart . Jeff Creech has said that LTs arent worth the price/performance gain over macs and has tuned many a 500rwhp car with mac mids.
Reply
Old May 7, 2005 | 02:46 PM
  #7  
Frosty's Avatar
12 Second Club
iTrader: (17)
 
Joined: Nov 2004
Posts: 1,639
Likes: 0
From: Near Philly,PA
Default

Granted I haven't installed my MAC's yet but this is the first I've heard of having to undo a motor mount...
Reply
Old May 7, 2005 | 02:56 PM
  #8  
SSCoulter's Avatar
Thread Starter
Launching!
iTrader: (4)
 
Joined: Jun 2004
Posts: 203
Likes: 0
From: North Little Rock, Arkansas
Default

I'm planning on lowering my car just a little at some point in the furture so the Mac's are going to be good for me. Plus, I am getting them really cheap! Sounds like it's a good comprimise without losing a whole lot of performance.
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 May 8, 2005 | 01:48 AM
  #9  
snake charmer's Avatar
TECH Fanatic
iTrader: (118)
 
Joined: Sep 2004
Posts: 1,510
Likes: 1
From: The south
Default

my install was pretty easy. i took the passenger side valve cover off and the header dropped right in. the drivers side i installed through the bottom of the sar just fine. as far as the ball flanges i cut mine off so the flange bolts right up to my 3" custom dual setup.
Reply




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