Headers without Catalytic converter - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

lechess · 08-21-2016, 03:38 PM

Ok I installed LT headers with off road pipes and the cabin of the car has a bad odor of exhaust fumes. Is it always going to be that way or get better once it gets tuned?

LimaCharlie · 08-21-2016, 03:49 PM

That's what happens when you remove cats. Personally, I love the raw exhaust smell.

The car is probably running rich now if you haven't tuned it. Get a good tune to lean out the A/F ratio. This will decrease the raw exhaust smell.

JusticePete · 08-21-2016, 03:50 PM

The tailpipe will have a different smell, but if you have exhaust smell in the cabin, you most likely have an exhaust leak. Carbon monoxide can sneak up on you. Check for leaks before you take another drive.

lechess · 08-21-2016, 04:52 PM

I lifted the car with a floor jack. Didn't look like there was black spots from an exhaust leak. But ill check again.

JusticePete · 08-21-2016, 04:56 PM

Quote:

Originally Posted by lechess

I lifted the car with a floor jack. Didn't look like there was black spots from an exhaust leak. But ill check again.

If there are fumes in the cabin when there were no fumes before, there has to be a leak.

motorhead · 08-21-2016, 04:56 PM

Quote:

Originally Posted by JusticePete

The tailpipe will have a different smell, but if you have exhaust smell in the cabin, you most likely have an exhaust leak. Carbon monoxide can sneak up on you. Check for leaks before you take another drive.

shouldn't have smell inside the car. Mostly an exhaust leak.

The ac system could be bring it in through the outside air inlet if there is an exhaust leak.

JusticePete · 08-21-2016, 07:13 PM

What gaskets did you use with the headers?

wrtowman · 08-21-2016, 07:19 PM

You should re-torque every bolt from the heads back.

Irace16 · 08-21-2016, 08:06 PM

I get the occasional whiff of exhaust while stopped when my roof or windows are open, but never while driving. Is that when you smell it? Took a little getting used to and as others have mentioned, a new tune will help a bunch... Did with mine

1KillerSS · 08-21-2016, 10:40 PM

Gotta love JusticePete, 99percent of the time, he is dead on........ Unless you have your windows down, you shouldn't be smelling fumes, an occasional wiff, with the windows down is common, but that's it.

If you didn't use new GM gaskets, you will probably want to use those. Re torque the header bolts, and check again for leaks.

lechess · 08-21-2016, 11:06 PM

Quote:

Originally Posted by JusticePete

What gaskets did you use with the headers?

I used GM gaskets. the gaskets that came with headers are cheap.

lechess · 08-21-2016, 11:13 PM

Cool. The header collector and the dummy cat looked to be clamped in a bad spot.. the dummy cat has slits cut into them and the clamp squeezed it open. I readjusted it. Other than that I ran out of time and will double check for others

lechess · 08-21-2016, 11:14 PM

Quote:

Originally Posted by JusticePete

What gaskets did you use with the headers?

I used GM gaskets. the gaskets that came with headers are cheap.

MrChrisLS3 · 08-21-2016, 11:58 PM

Quote:

Originally Posted by lechess

I lifted the car with a floor jack. Didn't look like there was black spots from an exhaust leak. But ill check again.

Really need to check with the car running. A new install is probably not going to show black marks. With the car running, you should be able to feel where the exhaust is leaking, if it is. A piece of good sized vacuum hose is a great tool to find this type of leak, one end to your ear and the move the other around the connections.

08-21-2016, 03:38 PM	#1
lechess Drives: LS3 Join Date: Jun 2015 Location: san antonio Posts: 75	Headers without Catalytic converter Ok I installed LT headers with off road pipes and the cabin of the car has a bad odor of exhaust fumes. Is it always going to be that way or get better once it gets tuned?

08-21-2016, 03:49 PM	#2
LimaCharlie Drives: 2011 Camaro SS/RS - 2004 Silverado Join Date: Mar 2010 Location: Las Vegas, NV Posts: 2,989	That's what happens when you remove cats. Personally, I love the raw exhaust smell. The car is probably running rich now if you haven't tuned it. Get a good tune to lean out the A/F ratio. This will decrease the raw exhaust smell. __________________ 2011 Summit White Camaro 1SS/RS -6.2 LS3, TR6060, 3.45, G80 2004 Black Silverado 1500 2WD Regular Cab, Short Bed -5.3 LM7, 4L60E, 3.42, G80 2014 White Caprice PPV -6.0 L77, 6L80E, 2.92, G80

08-21-2016, 07:19 PM	#8
wrtowman Drives: 2011 Camaro 1SS Join Date: Feb 2016 Location: Warner Robins Ga Posts: 778	You should re-torque every bolt from the heads back. __________________ 2011 SGM Camaro 1SS/RS A6 - Vengeance Racing built/tuned. 590RWHP/560RWTQ, ADM LSA Conversion, 2.5 Grip-Tec, ZL1 fuel pump, ADM FPCM, FIC1000, VRPD2 Cam and LS3 Conversion with all the internal goodies, American Racing 1 7/8 Headers, no cats, SW Retro Cat Back, ADM Intake, AFCO HX, Varimax Pump, Rotofab Reservoir, B&M Transmission Cooler, VMAX TB, Elite Engineering CC, BMR LCAs, Trailing Arms, Toe Rods, DSS 1000hp axles, ZL1 Bumper and Sideskirts, Night Owl Halos, Matte Black 20" Rohana RC-22 with 20x10-275s/20x11-315s, R1 Concept Premier Drilled/Slotted Rotors, Hawk Ceramic Pads.

08-21-2016, 08:06 PM	#9
Irace16 Drives: 2010 1SS RS M6 Join Date: Jan 2015 Location: Appleton, Wisconsin Posts: 521	I get the occasional whiff of exhaust while stopped when my roof or windows are open, but never while driving. Is that when you smell it? Took a little getting used to and as others have mentioned, a new tune will help a bunch... Did with mine __________________ Vararam intake, gmpp exhaust, borla stainless long tubes, cat less, jannetty tune, bmr lowering springs, heritage grill , smoked lenses

08-21-2016, 10:40 PM	#10
1KillerSS Too much is never enough! Drives: AGP TT SS [COTW] 4/20/15 Join Date: Feb 2014 Location: Toledo,OH Posts: 4,149 View My Garage	Gotta love JusticePete, 99percent of the time, he is dead on........ Unless you have your windows down, you shouldn't be smelling fumes, an occasional wiff, with the windows down is common, but that's it. If you didn't use new GM gaskets, you will probably want to use those. Re torque the header bolts, and check again for leaks. __________________ AGP TT kit, 54/57 Forged rotating assembly, Custom grind cam... Dual nozzle meth, ID850's, Livernois dual fuel pumps, ECS BAP, 25% UDP, 3 inch Magnaflow catback with X pipe, Mantic 9000 clutch, DSS 1000hp axles, DSS aluminum driveshaft, ZL1 rear end, solid subframe bushings, HE differential offset bushings, BMR Trailing arm, BMR toe rods, Lingenfelter LNC-2000,SJM Line Lock. 747 whp 714wtq *Build thread* http://www.camaro5.com/forums/showth...55#post8107855

08-21-2016, 03:50 PM	#3
JusticePete Drives: Camaro Justice Join Date: Jun 2007 Location: Virginia Posts: 20,174	The tailpipe will have a different smell, but if you have exhaust smell in the cabin, you most likely have an exhaust leak. Carbon monoxide can sneak up on you. Check for leaks before you take another drive.

08-21-2016, 04:52 PM	#4
lechess Drives: LS3 Join Date: Jun 2015 Location: san antonio Posts: 75	I lifted the car with a floor jack. Didn't look like there was black spots from an exhaust leak. But ill check again.

08-21-2016, 07:13 PM	#7
JusticePete Drives: Camaro Justice Join Date: Jun 2007 Location: Virginia Posts: 20,174	What gaskets did you use with the headers?

08-21-2016, 11:13 PM	#12
lechess Drives: LS3 Join Date: Jun 2015 Location: san antonio Posts: 75	Cool. The header collector and the dummy cat looked to be clamped in a bad spot.. the dummy cat has slits cut into them and the clamp squeezed it open. I readjusted it. Other than that I ran out of time and will double check for others