LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Exhaust Leak and BLM Question?

Thread Tools
 
Search this Thread
 
Old Oct 1, 2008 | 12:06 PM
  #1  
DAVE00's Avatar
Thread Starter
TECH Fanatic
15 Year Member
iTrader: (10)
 
Joined: Jul 2007
Posts: 1,739
Likes: 2
From: Houston, TX
Default Exhaust Leak and BLM Question?

Guys,

Still chasing down my split blm issues and just wanted to ask a quick question. I recently replaced my header gaskets and retorqued all my header bolts and used stage 8 locking ones to make sure they don't go anywhere. My y-pipe collector gasets look fine but I might have a slight leak (not 100% sure) on the pass side. Question could a small leak in the collector gaskets cause a false lean? I would think not as they are past/down stream from the O2's is this correct. If not then I am going to check the pass side primary again and go over the entire header for holes. Thanks.
Reply
Old Oct 1, 2008 | 04:35 PM
  #2  
tylert14's Avatar
12 Second Club
15 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (11)
 
Joined: May 2007
Posts: 550
Likes: 1
From: Transfer, PA
Default

Depends how close they are to the 02s. I've read that even downstream leaks a certain length downstream can still trick the 02s. I was having a hell of a time with split BLMs with the stock PCM. Check your header gaskets again, I thought I didn't have any leaks and when i pulled the motor I saw some visible leaks I couldn't see from the engine bay or from below the car.
Reply
Old Oct 2, 2008 | 07:50 AM
  #3  
DAVE00's Avatar
Thread Starter
TECH Fanatic
15 Year Member
iTrader: (10)
 
Joined: Jul 2007
Posts: 1,739
Likes: 2
From: Houston, TX
Default

Originally Posted by tylert14
Depends how close they are to the 02s. I've read that even downstream leaks a certain length downstream can still trick the 02s. I was having a hell of a time with split BLMs with the stock PCM. Check your header gaskets again, I thought I didn't have any leaks and when i pulled the motor I saw some visible leaks I couldn't see from the engine bay or from below the car.
Well took another look today and the O2 on the pass side (where my lean condition is) is very close to the collector flage on my JBA's (bout 1 inch away). I also see alot of soot on the bottom of the car under the collector so I think this might be my issue but I can't tell if it's old or new. I'm gonna go ahead and replace the collector gaskets and see what happens. I'll keep you posted. Anyone have any reccs on what brands to use???
Reply




All times are GMT -5. The time now is 10:28 AM.

story-0
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-1
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-2
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-3
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-4
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-5
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-6
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-7
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
story-8
Five Reasons the Camaro Was the Most Pivotal Player in the Pony Car Wars 2.0

The world was a better place when it was still around.

By Brett Foote | 2026-01-23 09:20:37


VIEW MORE
story-9
10 Reasons the LS7 Is GM's Most Extreme Naturally Aspirated V8 Engine Ever

Slideshow: The 7.0-liter LS7 was designed for absolute cutting-edge performance.

By Verdad Gallardo | 2026-01-07 18:36:00


VIEW MORE