k1500 x-haust - Pirate4x4.Com : 4x4 and Off-Road Forum

g.schucks · 08-29-2005, 12:29 PM

I have talked to many ppl and am tied for half saying one thing half saying the other. First off, I have a 98' K1500 Z71 with 5.7L engine. The stock x-haust has each header coming down going into a separate CAT for each side then both pipes into one muffler and a single side exit tailpipe. My question is when I redo my x-haust I originally wanted to cut off the muffler and just put in a turn down after each CAT. But I have had people say that I should just cut off the CATs and use a separate muffler for each side. I do not have to worry about emissions as my state has done away with our testing. I used to have a 1993 Camaro Z28 5.7L LT1 with a cutout after the only CAT and I loved the sound of that. I am looking for about the same sound and some possible HP gain as I free up some flow. But where is the line between freeing up flow and loosing back pressure??? One of the pluses to just removing the muffler is that I can leave the CATs alone sense there are two sensors(1 before the cat and 1 after) that I can leave there and not trip a code in the computer. I have seen relays to bypass these but haven't really looked into those yet. I HAVE to eventually re-route the x-hast b/c of front driveshaft clearance once I lift the truck.

Thanks for any help guys.
g.schucks

lumpdog · 08-29-2005, 01:11 PM

Sooooo, ummm, yeah, what's your point again???

Trailblazr81 · 08-29-2005, 01:44 PM

Well for best power go with dual mandrel bent pipes and good high flow mufflers such as Flowmaster, Magna Flow, Dynomax, etc. Just stay away from the cheap $20 "Turbo" mufflers. If you can loose the cats do it. After a while they could get clogged or Ive seen a couple cases where the internals break up and shoot out your tailpipe!! I like the sound of these... http://www.classicchambered.com/classic/sounds.html

g.schucks · 08-30-2005, 07:29 AM

Quote:

Originally Posted by lumpdog

Sooooo, ummm, yeah, what's your point again???

Cut of Cats and use mufflers or leave cats and ditch muffler???

3/4ton62gmc · 08-30-2005, 11:42 PM

I would leave tha cats on and use a good muffler like one of the mufflers named above, I have a lot of experience with Spin Tech mufflers there very free flowing, have a great deep sound and willl get you about 20Hp over stock. Also a cat will not fail if the vehicle is running properly.My .02$

Mr. Pink · 08-31-2005, 02:12 PM

The cats are frikkin huge, I'd leave them in. Even the rednex around here leave the cats on when they straight-pipe + megaphone tip their exhaust. Cut them off, it costs more money and you might trigger a check engine light or worse.

mudslinger99 · 08-31-2005, 06:05 PM

If your worried about tripping a sensor then leave the cats on if not take them off.. If you do decide to add mufflers then go with Flowmaster 40 series.. Or if you want something that is close to those but less money then Summit has a muffler that is close..

08-29-2005, 12:29 PM	#1 (permalink)
g.schucks Registered User Join Date: Jul 2005 Member # 50695 Posts: 28	k1500 x-haust I have talked to many ppl and am tied for half saying one thing half saying the other. First off, I have a 98' K1500 Z71 with 5.7L engine. The stock x-haust has each header coming down going into a separate CAT for each side then both pipes into one muffler and a single side exit tailpipe. My question is when I redo my x-haust I originally wanted to cut off the muffler and just put in a turn down after each CAT. But I have had people say that I should just cut off the CATs and use a separate muffler for each side. I do not have to worry about emissions as my state has done away with our testing. I used to have a 1993 Camaro Z28 5.7L LT1 with a cutout after the only CAT and I loved the sound of that. I am looking for about the same sound and some possible HP gain as I free up some flow. But where is the line between freeing up flow and loosing back pressure??? One of the pluses to just removing the muffler is that I can leave the CATs alone sense there are two sensors(1 before the cat and 1 after) that I can leave there and not trip a code in the computer. I have seen relays to bypass these but haven't really looked into those yet. I HAVE to eventually re-route the x-hast b/c of front driveshaft clearance once I lift the truck. Thanks for any help guys. g.schucks

08-29-2005, 01:44 PM	#3 (permalink)
Trailblazr81 Registered User Join Date: Jun 2005 Member # 48446 Posts: 83	Well for best power go with dual mandrel bent pipes and good high flow mufflers such as Flowmaster, Magna Flow, Dynomax, etc. Just stay away from the cheap $20 "Turbo" mufflers. If you can loose the cats do it. After a while they could get clogged or Ive seen a couple cases where the internals break up and shoot out your tailpipe!! I like the sound of these... http://www.classicchambered.com/classic/sounds.html Last edited by Trailblazr81; 08-29-2005 at 01:51 PM.

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

08-29-2005, 01:11 PM	#2 (permalink)
lumpdog Rock God Join Date: Mar 2005 Member # 44659 Location: Mtn Home, Idaho Posts: 1,237	Sooooo, ummm, yeah, what's your point again???

08-30-2005, 11:42 PM	#5 (permalink)
3/4ton62gmc Wheeler Join Date: Nov 2004 Member # 38880 Location: Phoenix Az. Posts: 247	I would leave tha cats on and use a good muffler like one of the mufflers named above, I have a lot of experience with Spin Tech mufflers there very free flowing, have a great deep sound and willl get you about 20Hp over stock. Also a cat will not fail if the vehicle is running properly.My .02$

08-31-2005, 02:12 PM	#6 (permalink)
Mr. Pink Registered User Join Date: Dec 2004 Member # 40383 Posts: 219	The cats are frikkin huge, I'd leave them in. Even the rednex around here leave the cats on when they straight-pipe + megaphone tip their exhaust. Cut them off, it costs more money and you might trigger a check engine light or worse.

08-31-2005, 06:05 PM	#7 (permalink)
mudslinger99 Registered User Join Date: Oct 2004 Member # 37519 Location: here Posts: 1,266	If your worried about tripping a sensor then leave the cats on if not take them off.. If you do decide to add mufflers then go with Flowmaster 40 series.. Or if you want something that is close to those but less money then Summit has a muffler that is close..