L99 Resonator removed 2013 ss automatic - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

pecothern · 11-07-2016, 11:06 AM

The car I bought used is an L99. The huge resonator has been removed. They added the exhaust that has 4 tips and it has the vacuum cutouts in the back but there is no vacuum hoses attached. It looks like the flappers are open all the time. it sounds pretty good. I noticed there is no "H" pipe. Is it needed and would it change the sound/ performance much?

Dimitrim · 11-07-2016, 11:41 AM

Not having the H-Pipe, you will loose a lot of low end torque. You will not be able to do burn outs. I myself love doing burn outs. It is cheap to have an h-pipe welded in.

Your fuel economy will also suffer.

Neoclasiccl · 11-07-2016, 02:48 PM

Is there an xpipe?

audiowhiz · 11-07-2016, 02:55 PM

I put an X-pipe where the resonator was after I removed it.
The muffler shop was very much against just putting straight pipes instead.

christianchevell · 11-07-2016, 06:28 PM

H pipe is contained inside the "suitcase" resonator of the l99 so yes you do need a crossover either h or x. It makes the engine perform better.

Moto-Mojo · 11-07-2016, 07:29 PM

Someone please explain to me how a resonator / muffler delete can rob performance. Is it a proper back pressure thing??? Seriously, I don't know.

Dimitrim · 11-07-2016, 07:54 PM

Quote:

Originally Posted by Moto-Mojo

Someone please explain to me how a resonator / muffler delete can rob performance. Is it a proper back pressure thing??? Seriously, I don't know.

V-8's need a crossover to perform well. H crossover gives you low end torque. X gives you top end performance.

Moto-Mojo · 11-07-2016, 08:05 PM

And these pipe arrangements are in the resonator or muffler or both? (or are the muffler/reso one in the same?)

qcman · 11-08-2016, 11:09 AM

Quote:

Originally Posted by Moto-Mojo

And these pipe arrangements are in the resonator or muffler or both? (or are the muffler/reso one in the same?)

Good question I've been struggling to understand this too as I was thinking of deleting the 2 rear mufflers near the tips. I assume the resonator with H pipe is closer to the Cats?

985ss · 11-08-2016, 12:17 PM

Quote:

Originally Posted by Moto-Mojo

Someone please explain to me how a resonator / muffler delete can rob performance. Is it a proper back pressure thing??? Seriously, I don't know.

It's the x or h pipe that is what helps your performance. The engine is being exhausted in alternating pulses, so when one bank has very high pressure moving through the exhaust, the x or h allows some of the exhaust to move to the other side of the exhaust where the pressure is lower.

11-07-2016, 11:06 AM	#1
pecothern Drives: 2013 SS VERT Join Date: Oct 2016 Location: 39212 Posts: 29	L99 Resonator removed 2013 ss automatic The car I bought used is an L99. The huge resonator has been removed. They added the exhaust that has 4 tips and it has the vacuum cutouts in the back but there is no vacuum hoses attached. It looks like the flappers are open all the time. it sounds pretty good. I noticed there is no "H" pipe. Is it needed and would it change the sound/ performance much?

11-07-2016, 11:41 AM	#2
Dimitrim Dimitri Drives: 68 GTO 455 Ram Air; 2014 Camaro ZL1 Join Date: Jan 2014 Location: Novato, California Posts: 602 View My Garage	Not having the H-Pipe, you will loose a lot of low end torque. You will not be able to do burn outs. I myself love doing burn outs. It is cheap to have an h-pipe welded in. Your fuel economy will also suffer. Last edited by Dimitrim; 11-07-2016 at 01:04 PM.

11-07-2016, 06:28 PM	#5
christianchevell old school chevy rodder Drives: 2013 2SS/RS Manual,DM exhaust,CRT Join Date: Jul 2012 Location: Oregon Posts: 5,587 View My Garage	H pipe is contained inside the "suitcase" resonator of the l99 so yes you do need a crossover either h or x. It makes the engine perform better. __________________ 2021 Wild Cherry ZL1 A10, Sunroof, Data, Carbon, Nav, RotoFab Dry CAI, Elite x2, Borla ATK, Driveshaft shop

11-07-2016, 07:29 PM	#6
Moto-Mojo Fast Cars and Old Guitars Drives: 2015 2SS RS (L99, baby!) Join Date: Apr 2012 Location: N. CA Posts: 3,973	Someone please explain to me how a resonator / muffler delete can rob performance. Is it a proper back pressure thing??? Seriously, I don't know. __________________ “I don’t want to belong to any club that would have me as a member.” - Groucho Marx

11-07-2016, 08:05 PM	#8
Moto-Mojo Fast Cars and Old Guitars Drives: 2015 2SS RS (L99, baby!) Join Date: Apr 2012 Location: N. CA Posts: 3,973	And these pipe arrangements are in the resonator or muffler or both? (or are the muffler/reso one in the same?) __________________ “I don’t want to belong to any club that would have me as a member.” - Groucho Marx Last edited by Moto-Mojo; 11-07-2016 at 08:27 PM.

11-07-2016, 02:48 PM	#3
Neoclasiccl Drives: 2012 Camaro SS L99 Join Date: Apr 2012 Location: Jacksonville Fl Posts: 232	Is there an xpipe?

11-07-2016, 02:55 PM	#4
audiowhiz Drives: 2005 Corvette M6 Join Date: Sep 2016 Location: Knoxville- TN Posts: 154	I put an X-pipe where the resonator was after I removed it. The muffler shop was very much against just putting straight pipes instead.