Exhaust Post your questions and suggestions about stock or aftermarket exhaust setups. Third Gen exhaust sound files and videos!

Yey!? Exhaust cut out after cats if there are two cats?

Thread Tools
 
Search this Thread
 
Old 03-13-2003, 10:02 PM
  #1  
Senior Member
TGO - 10 Year Member
Thread Starter
 
raptere's Avatar
 
Join Date: Oct 2002
Location: Northwest Chicago Suburbs
Posts: 562
Received 46 Likes on 40 Posts
Car: 1991 Camaro Z-28, Durango R/T
Engine: 5.7L TPI W/ HSR
Transmission: 700R4 Tuned Shift 2600 Stall
Axle/Gears: 3.23 10 Bolt Posi W/ Disks
Hey!? Exhaust cut out after cats if there are two cats?

I am looking at getting the borla cat back system. it has teh cutout after the cats to bypas the muffler. I know people have sail that you should always put the cutouts before the cats on the headers but if you have dual cats that will the restriction from that be negligible. How will it effect the power out put and the sound of my exhaust system. I currently have stock exhaust but i do plan to get the cat back system and also two highflow cats from Magnaflow or similar and some coated slp headers W/ AIR.

Thanks for the help guys.

Raptere

1991 Camaro Z-28
5.7L TPI dual cat
Bone Stock (So Far)

Last edited by raptere; 03-14-2003 at 01:54 PM.
Old 03-14-2003, 09:10 PM
  #2  
Supreme Member

iTrader: (1)
 
Sickness91Z28's Avatar
 
Join Date: Mar 2001
Location: Chesterfield, Indiana
Posts: 4,226
Likes: 0
Received 6 Likes on 5 Posts
Car: 1991 Z28 Camaro
Engine: 5.7
Transmission: Jasper 700R4 Stage II
Axle/Gears: 3.23 For Now
I've got an electric cut-out on my 91 Z28....located after the cats in the 3 inch Intermediate pipe. Both of my cats are removed.....I hope you like the sound of NASCARS...because.....when mine is all the way open....that's what it sounds like.....it's really raw....and VERY VERY loud....I had my stereo on 20....and it even drowns it out......but..it's cool...because..by the flip of a switch.....I can have it to just Flowmaster volume...
Attached Thumbnails Yey!? Exhaust cut out after cats if there are two cats?-mccordcutout.jpg  

Last edited by Sickness91Z28; 03-14-2003 at 09:14 PM.
Old 03-15-2003, 12:26 AM
  #3  
Senior Member
TGO - 10 Year Member
Thread Starter
 
raptere's Avatar
 
Join Date: Oct 2002
Location: Northwest Chicago Suburbs
Posts: 562
Received 46 Likes on 40 Posts
Car: 1991 Camaro Z-28, Durango R/T
Engine: 5.7L TPI W/ HSR
Transmission: 700R4 Tuned Shift 2600 Stall
Axle/Gears: 3.23 10 Bolt Posi W/ Disks
What if you still have two cats there?
Old 03-15-2003, 10:58 PM
  #4  
Banned
 
89IRO's Avatar
 
Join Date: Aug 2002
Location: So Cal
Posts: 910
Likes: 0
Received 0 Likes on 0 Posts
I've got the one cat setup on my car, so I would only need one cut-out. How much does one of these cost? What brands are out there? Also, I live in CA, so I am strongly assuming having this will be an automatic fail at smog inspection, am I right? -89IRO
Old 03-16-2003, 12:27 AM
  #5  
Senior Member
TGO - 10 Year Member
Thread Starter
 
raptere's Avatar
 
Join Date: Oct 2002
Location: Northwest Chicago Suburbs
Posts: 562
Received 46 Likes on 40 Posts
Car: 1991 Camaro Z-28, Durango R/T
Engine: 5.7L TPI W/ HSR
Transmission: 700R4 Tuned Shift 2600 Stall
Axle/Gears: 3.23 10 Bolt Posi W/ Disks
you can get the cut outs at summit or jegs. the whole point of them is there is a plate with the plate on all of the exhaust goes through the entyre system (Fully Legal) Only when you want extra power in lets say a race you can take off the plate and insted of the exhaustgoing through the muffler and the cats depending where you put it does it become illeagl because it is basicly then a strait pipe.
Old 03-16-2003, 11:45 AM
  #6  
Banned
 
89IRO's Avatar
 
Join Date: Aug 2002
Location: So Cal
Posts: 910
Likes: 0
Received 0 Likes on 0 Posts
you can get the cut outs at summit or jegs. the whole point of them is there is a plate with the plate on all of the exhaust goes through the entyre system (Fully Legal) Only when you want extra power in lets say a race you can take off the plate and insted of the exhaustgoing through the muffler and the cats depending where you put it does it become illeagl because it is basicly then a strait pipe.



I know having it closed would be, technically, legal, but when you have to get a visual smog inspection, I don't think this will work. Anybody else? -89IRO
Old 03-17-2003, 03:58 PM
  #7  
Senior Member
 
1MEAN92RS's Avatar
 
Join Date: Dec 2001
Location: Blacksburg, VA
Posts: 731
Likes: 0
Received 2 Likes on 2 Posts
Car: '92 Rally Sport
Engine: LO3
Transmission: 700R4
Here in VA a cutout will not pass if installed before the cat (as it should be), even if it is not electric. Anything after the cat is fair game though.
Old 03-17-2003, 05:09 PM
  #8  
Supreme Member
 
89blackGTA's Avatar
 
Join Date: Mar 2002
Location: Central CA
Posts: 1,805
Likes: 0
Received 1 Like on 1 Post
Car: 89 Black GTA
Engine: 5.7 TPI
Transmission: 700R4
I had the Borla on my 96 Z28. I didnt really notice any more power with it open, but the sound was AWESOME! If you were going to get a cutout I would not have spent the money on the borla. And two cats flow much better than one.

Brian
Old 03-17-2003, 10:22 PM
  #9  
Moderator

iTrader: (1)
 
Kevin91Z's Avatar
 
Join Date: Jul 1999
Location: Orange, SoCal
Posts: 10,947
Received 21 Likes on 18 Posts
Car: 1990 Pontiac Trans Am
Engine: 355 TPI siamesed runners
Transmission: Tremec T56
Axle/Gears: 12-Bolt 3.73
My cutout is right after the dual cats, where they join together. It works just fine for me there, but I've never had it dynoed to see the difference.
Old 03-17-2003, 10:58 PM
  #10  
Banned
 
89IRO's Avatar
 
Join Date: Aug 2002
Location: So Cal
Posts: 910
Likes: 0
Received 0 Likes on 0 Posts
They say that the exhaust isn't as loud if you're running cat(s), so if you installed the cut-out after the cat(s) it wouldn't be "open headers" but it would still be very loud, right? I will go on the so cal board to see if this is legal. -89IRO
Old 03-18-2003, 11:01 AM
  #11  
Senior Member
 
1MEAN92RS's Avatar
 
Join Date: Dec 2001
Location: Blacksburg, VA
Posts: 731
Likes: 0
Received 2 Likes on 2 Posts
Car: '92 Rally Sport
Engine: LO3
Transmission: 700R4
Originally posted by 89IRO
so if you installed the cut-out after the cat(s) it wouldn't be "open headers" but it would still be very loud, right?
You wouldn't believe how much quieter it will be with a cat than without... Nothing like open headers at all. If you have free flow cats it might be louder than than with the stockers, but if you're gonna have cats there isn't that much to gain from a cutout behind them besides a few more db's.

Later,
Harry
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
chazman
Tech / General Engine
8
08-28-2018 03:25 PM
formula_novice
Exhaust
32
09-05-2015 03:58 AM
Out-Cast
Exhaust
6
08-22-2015 07:49 PM
gta power
Exhaust
1
08-13-2015 06:15 AM



Quick Reply: Yey!? Exhaust cut out after cats if there are two cats?



All times are GMT -5. The time now is 05:54 AM.