Headers installed

[finatic]

I have a bit of a surprise result. My 2010 L99 had stock manifolds and cats with a FlowMaster cat back system. I had installed 2" Hooker Blackheart long tube headers, FlowMaster high flow cats, an x pipe and then had it connected to what was left for the cat back system. Much to my surprise I have no check engine condition and I believe the car is quieter. Any suggestions for replacing the current FlowMaster mufflers with something a little more manly sounding?

[CamaroDreams76]

You won't get a CEL immediately. The O2 sensors need to go through a check/cycle. Mine used to do it about every 150/200 miles if I recall correctly.

I too thought my car was quieter at idle. Thats about it, just idle.

[finatic]

I have yet to get out and push it. It's raining here in Florida today.

[DirtyDirt]

I have a Borla ATAK cat back system on mine... I really like the way it sounds over stock. Definitely louder/throatier on start up, and when you stomp the skinny pedal, at cruising speed it is not much loader than stock, with none of the dreaded "drone". Many others on here have more input and experience than me

[FasNuf]

Your Long Term Fuel Trims will be making a fueling adjustment to correct the lean condition that the headers might create. If the LTFT percentage gets high enough, the ECM will trip the CEL. You can probably get a fairly inexpensive scanner that reads LTFT and see how well your car is compensating, but ultimately a tune is a better idea.

[SS_Dave]

Originally Posted by finatic

I have yet to get out and push it. It's raining here in Florida today.

Maybe go have it properly tuned before you do. You'll get more out of the headers than noise that way.

[finatic]

A full tune is in my immediate future for sure. Thanks all.

[pyroguy]

You'll eventually get a CEL. It's inevitable.

As for loud sound, check out Noweeds Exhaust diverters.

[finatic]

According to the shop I currently have FlowMaster 40 series mufflers. It's not what I expected after installing headers and x pipe. I'm thinking about changing them out for FlowMaster Flow FX mufflers. Anyone using those?

[rdavis]

Originally Posted by CamaroDreams76

You won't get a CEL immediately. The O2 sensors need to go through a check/cycle. Mine used to do it about every 150/200 miles if I recall correctly.

I too thought my car was quieter at idle. Thats about it, just idle.

As said above my cel would only come on periodically. I would just clear it off with my code reader. Shortly after got it tuned & no more light.

[rdavis]

Originally Posted by finatic

According to the shop I currently have FlowMaster 40 series mufflers. It's not what I expected after installing headers and x pipe. I'm thinking about changing them out for FlowMaster Flow FX mufflers. Anyone using those?

I personally am not a fan of flowmasters. Had them on my car for a long time until I found a set of factory NPP mufflers. Closed they are very civilized U open they just scream. No drone at all. I'm in love with them.