[Nilly Welson]

Extended warranty running out, thinking about headers with my stock NPP. Is a tune necessary? How much HP can I expect with Long Tubes? I don't want it any louder, will LT headers make it louder with my NPP? What brand recommendation?

[arpad_m]

I have Kooks headers and green cats with the factory NPP, and they made the car louder all around, except maybe cruising at 1400 rpm.

Cold starts wake the dead, and at WOT she sounds like an vicious, snarling animal (that eats mustangs), but in a good way. So, if you don't want more volume, don't get LT headers.

Also, yes, I think a tune is a must to run properly with headers.

[s346k]

a friend of mine had a 17 ss 1LE with cai air box, kooks long tubes and cats into the remaining stock exhaust. his car was untuned.

in track mode his car was slightly louder than mine, when mine was bone stock. we raced a lot. my car was a touch faster than his.

a tune isn't required but definitely necessary to see any gains with those mods.

[Chrome383Z]

I have 2” CSP long tubes, GESI cats, into stock NPP. Love it. Echo air pads comments. IMO it’s the best sounding exhaust.

Now eliminate the cats and the stock NPP goes from sounding awesome to a raspy tin can. So I would keep CATs and you’ll get the added benefit of not smelling bad.

[arpad_m]

Originally Posted by Chrome383Z

I have 2” CSP long tubes, GESI cats, into stock NPP. Love it. Echo air pads comments. IMO it’s the best sounding exhaust.

Now eliminate the cats and the stock NPP goes from sounding awesome to a raspy tin can. So I would keep CATs and you’ll get the added benefit of not smelling bad.

Haha, isn't autocorrect hilarious at times. Never been called "air pad" before, although "air pod" did happen a few times

[Spaceme1117]

Originally Posted by arpad_m

I have Kooks headers and green cats with the factory NPP, and they made the car louder all around, except maybe cruising at 1400 rpm.

Cold starts wake the dead, and at WOT she sounds like an vicious, snarling animal (that eats mustangs), but in a good way. So, if you don't want more volume, don't get LT headers.

Also, yes, I think a tune is a must to run properly with headers.

100% agree. I also have Kooks headers with cats going into the stock NPP.

A tune is necessary.

Cold starts are startling to say the least but once the car idles down, its actually pretty quiet.

At first after the headers, I was a bit uncomfortable about the increased sound but I love it now.

But headers really help the engine a lot. You will gain both power and torque but what is really surprising is that headers will extend the power and torque a significant amount. The upper RPM gains are similar to adding a cam to a Gen 4 engine. I don't know what it is about the Gen 5's but it is a special engine.

[Trochoidal]

Originally Posted by Nilly Welson

Extended warranty running out, thinking about headers with my stock NPP. Is a tune necessary? How much HP can I expect with Long Tubes? I don't want it any louder, will LT headers make it louder with my NPP? What brand recommendation?

LT’s into “high flow” cats with X-pipe connected into NPP sound great in any mode except tour. Cold start it in tour mode and it “barks” for maybe 15 seconds. Any other mode for cold start makes some ruckus. In sport mode off of a light the valves are opened and close by third gear (A8). In track mode, above 2400 valves open and the car sounds great too.

5th gear at 2500 on the highway, in an A8, and the exhaust just sounds “right”.

I’d suggest LT’s into factory NPP all day.

The only sound I’m not fond of is when the car is in tour mode at any RPM. It’s just too raspy.

[Nilly Welson]

Any sound clips and drive bys?��

[enzia35]

I think this is a good representation of long tube clips.
https://youtu.be/FU2qxmxl5xQ

[Nilly Welson]

Originally Posted by enzia35

I think this is a good representation of long tube clips.
https://youtu.be/FU2qxmxl5xQ