markadamsagent

2013 C6 Base vert, About to purchase some 1 7/8 long tubes and then have it tuned and dyno car already has corsa sport and vara CAI wondering what type of gains I should be expecting I’m in CA, I mean it’s got to be worth it right?

Sphurley

How would you smog it? I went with Manifolds, cats from a ZR1 or Z06 and put 3" BB X pipe and mufflers. It 80% of headers without the inspection issues.
Car made 425 rwh with a A6 before I SC'd it.

Spaceme1117

Expect 20 t0 25 whp possibly 30. Will you be able to feel a gain? Probably. Your car will have much better exhaust sound.

Is it worth it? That is something you will need to decide. If you get a high quality set of headers and catted x-pipe (which I do recommend) from Kooks, Stainless Works, etc. and a dyno tune, figure spending $2500. And you will not pass Ca smog inspection and will need to put the stock exhaust back on each time.

Going with a Z06 exhaust setup, you will pay about $1000 less but also be down 5 to 10 hp.

Dcasole

Is it worth it ... heck yes , it's not just 30 To 40 HP , its 30 to 40 across a good part of the RPM band , your car will pull like a freight train ...

Dave

tblu92

Of cousre 25 30 hp is worth it
HP is worth it BUT in calif LT headrs are illegal So be prepared to go back to stock every 2 years or have your smog done under the table
The reason LT headers are illegal in most states is bescuse with LT's the front 02 bungs are moved as much as 3ft aft
This makes them not heat up correct;y and read wrong---Without tuning they will make your engine run very rich and many times you will gain no HP advantage or very little---Tuning can fix this
Also be prepared to change your front 02's every year or so as they will foul out just as spark plugs do---
Worth it If you are a gear head and always want max HP then yes----But as a daily driver you open up a can of worms without yearly maintenance

Dcasole

Never hear of having to change 02 sensors every year of two .... and I have had plenty of cars with headers ....as well as the many cars in our group

Dave

tblu92

Well it sounds like no one in your group has ever had a wideband 02 installed on there exhaust after a LT installation
While Stoich fueling at P/T has to be 14.68-1 after inatalling LT's it changes to a richer mixture at P/T anywhere from 14.1 to 14.3 -Even though yeah it still runs OK------it is pig rich I can almost gaurantee you if you swiped your fingers in the exhaust pipes your fingers will have black soot on them---The bad thing is that this richness can carry over to WOT as well !!
That is why it takes special tuning to get the 30 HP expected with LT hdrs---You MUST adjust your front 02 switching points to get them back to Stoich -- Normally like .450 millivolts---I can almost be sure your switching point averages are beyond .500 millivolts ( larger averages are richer)

Dcasole

Blue , no disrespect but I am confident that the tuner we use understands how to tune and infact does use a wideband and a dyno ...... and they never heard of having to replace 02 sensors because of tuning .....
Dave

tblu92

You mis inderstood me replacing the front 02's are not needed becaue of TUNING It is because of the LT headers---They will typically last 2 years or so with LT's Many tuners reccomend installing the rear 02 sensors onto the front locations because of this as the rears are far more sensitive and will heat up better --making them last longer and read more accurately
I doubt if you tuner was concerned about 02 readings at P/T Most dyno tuners only check the engine at WOT in the gear raio that is 1-1----and not corcerned about 02 switching points--Only WOT top HP Dis he tell you what was the average 02 readings at P/T / I am sure he did not I am quite sure you are leaving HP on the table by not addressing the P/T 02 averages----

Orion2011

Long tube headers are not street legal in CA. Unless you're going to swap the manifolds back on every time it's up for inspection...

tblu92

That's not what I said I said with LT headers you need to adjust the 02 switching points to get your 02 averages back close to .450 millivolts which is Stoich fueling at P/T (14.68-1 )
If you don't your 02's will eventually foul and then flatline at .450 without proper oscilation that has to happen being that the 02's must rapidly change from .100 to .950 millivolts with an average of .450 ( larger averages mean a richer P/T fueling)
You can do whatever you like But this is what I was taught at EFILIVE training many years ago---It is the basics of closed loop tuning--for P/T on any computer controlled gas engine----
PS If your tuner only did Dyno tuning Then all he did was adjust WOT fueling and spark in the gear ratio closets to 1:1 And did not DRIVE the car at all at P/T to dial in the closed loop tuning--Including the 02's The front 02 tuning must only be data logged while driving on the street during P/T only and Not WOT---ALSO the richness at P/T will be carried over to WOT as well--as if you have a positive fuel trim "just before going to WOT " that % is carried over to WOT as a lean safety--This stuf is complicated as even an anomily at P/T can also affect WOT as well---
You always need to sort out the P/T fueling before ever trying to make changes at WOT----Believe me or not I don't care--Just trying to help