Tech / General Engine Is your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!
Sponsored by:
Sponsored by: CARiD

Lg4 2 1/2 cat back to stock 2 1/4 cat?

Thread Tools
 
Search this Thread
 
Old May 11, 2012 | 08:47 AM
  #1  
Slowpoint0's Avatar
Thread Starter
Member
 
Joined: May 2012
Posts: 120
Likes: 0
Car: 1986 t/a
Engine: Lg4 305 carb
Transmission: 700r4 auto
Axle/Gears: 2.73 posi
Lg4 2 1/2 cat back to stock 2 1/4 cat?

New here,
I have a 86 factory stock trans am lg4 5.0 700r4.
Iv read all the upgrade posts cams, headers back, gears, duel snorkel air.

My question is. I have a dynomax super turbo 2 1/2" cat back system
I need to connect it to factory 2 1/4 cat. How do I do it? What adaptors if any?
I am new to building up a car "mechanics for dumbies" was printed just for me!!!
Thank you for any help. I do know that car has ALL its emissions stuff..
Reply
Old May 11, 2012 | 10:30 AM
  #2  
TheMonster's Avatar
Senior Member
 
Joined: Jun 2009
Posts: 511
Likes: 0
From: Evansville, IN
Car: 1983 Z28
Engine: Forged 355
Transmission: 700r4
Axle/Gears: 2.73
Re: Lg4 2 1/2 cat back to stock 2 1/4 cat?

First, Welcome to the site! There is a ton of information here, read up!

What state do you live in? I would ditch the cat, your local auto part store will have a pipe that will replace the cat, and several adapters.
Reply
Old May 11, 2012 | 08:55 PM
  #3  
Slowpoint0's Avatar
Thread Starter
Member
 
Joined: May 2012
Posts: 120
Likes: 0
Car: 1986 t/a
Engine: Lg4 305 carb
Transmission: 700r4 auto
Axle/Gears: 2.73 posi
Re: Lg4 2 1/2 cat back to stock 2 1/4 cat?

I would but what about the little pipe that comes off of it?? I don't want lights on or anything!
Reply
Old May 11, 2012 | 09:37 PM
  #4  
seawolf18's Avatar
Junior Member
iTrader: (1)
 
Joined: Jun 2005
Posts: 84
Likes: 0
From: South Dakota
Car: 91 Trans AM
Engine: 305 TPI
Transmission: T-5
Axle/Gears: 3.42
Re: Lg4 2 1/2 cat back to stock 2 1/4 cat?

The little pipe connects to the smog pump. All a smog pump does is inject fresh air into the cat and exhaust manifolds to try to lower emissions. By removing the cat and smog systems, you will not set a check engine light. There are no engine sensors past the cat on these cars. If you state doesn't have emissions testing, I would just chop the cat off.
Reply
Old May 12, 2012 | 09:32 PM
  #5  
Slowpoint0's Avatar
Thread Starter
Member
 
Joined: May 2012
Posts: 120
Likes: 0
Car: 1986 t/a
Engine: Lg4 305 carb
Transmission: 700r4 auto
Axle/Gears: 2.73 posi
Re: Lg4 2 1/2 cat back to stock 2 1/4 cat?

No emissions, if I cut off cat it looks like to much of a bend in the pipe to get adaptor to seal right. Yes I'm clamping cant weld and can't afford to have it done.
Anyone have a picture of cat removed with a clamp??

Thanks guys
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
TreDeClaw
Theoretical and Street Racing
11
Jun 22, 2021 08:21 PM
Vintageracer
Camaros for Sale
12
Jan 10, 2020 05:33 PM
bbsr72
Brakes
0
Aug 12, 2015 10:44 AM
dhonda200
Transmissions and Drivetrain
6
Aug 11, 2015 11:50 PM
drathaar907
TPI
0
Aug 6, 2015 04:20 PM




All times are GMT -5. The time now is 11:58 AM.