C6 Corvette Melrose Headers give me less power????
 

Hello.
Im new to CF and to Corvette in general. I got 2007 C6 Base automatic transmission.
Installed Airaid intake and Melrose coated Headers 1 3/4 prime and 3 exhaust tube, hi flow cats and x pipe 3". All pipes 3" but left OEM mufflers with 2,5" pipe from x pipe to muffler.
i feel less power in car after putting in $1400 I exhaust (parts and labor)
What did I do wrong? Do I need to change exhaust to create better flow? Should I take out hi flow cats and put resonators or straight pipe? Do I need tune?
Dont really understand. Thought will get more power.
Thank you all for help.

what else can I do to add more power for reasonable $$$$

My 1-3/4 ARH felt better after install before a tune. Anywho...you should get a tune after headers and intake. The difference between cats and no cats is only a couple HP.

Tune
 

So I need to Dino it or I can tune it with let's say SCT tuner witch has some tunes in it already?

I have an 06 with Melrose headers and I also have an Airaid CAI. My car had noticeably more power immediately after the header install. If yours is making less power something is definitely wrong. You could have a bad or shorted O2 sensor that could be your problem. If that's the case you should be showing a CEL.

CEL came up today. O2 sensors on both sides. With this cats I can not do anything but either tune to remove it or put spacer in between O2 sensor and cats so it won't read actual values.

Surprised your butt byno is not feeling the $1400. You're at least being realistic and not convinced it's a beast now.

A tune is necessary to get these mods to perform correctly. However, please consider a real tune. Besides doing practically nothing, these canned tuners like the one you're proposing can be problems in themselves the way they need to lock/marry the tuner to the ECM. Read this thread active right now in general.

https://www.corvetteforum.com/forums...r-network.html

Just saw this, and wondered why you weren't reporting a CEL in the first post. What CELS?

Both rear O2s, or all four (fronts and backs)?

When you go headers, regardless of whether you run cats or not, a tuner will usually just disable all the DTCs on the rear sensors. The fronts, however is where the tune is needed. With headers, the sensors end up two feet further downstream from the actual exhaust event they are using to give the ECM feedback for fueling. This much larger delay has to be accounted for in the tune, otherwise, you're not going to get any performance gain from the headers and hurting you instead.

I know I've read SCT builds a canned downloadable tune for headers....but....I wouldn't do it.

The first thing I would do is to check the fuse for the o2s. If it's blown you probably have a sensor that shorted against the frame or the header tubes.
On my Melrose headers all four O2s are reporting and I've had no issues.
im running a tune from Lew at diablo sport

So if I will get like diablo tuner do you think it will work for me?

Any suggestions on tune or tuner?

How did you get tune and how did you uploaded tune to the system?

You get the tune by contacting Lew on Diablos website. Custom tunes will be e-mailed to you . You load the tune from your computer to the tuner. Then plug the tuner into the OBD2 port in your car to install tune. Sounds like a lot but its really easy

Thank you. Will do that, hope will bring my vett to live :)

What tuner did you use. It's a few of them, not really sure witch one to pick.

I would find a local tuner who can do your car. IMHO you get a better tune that way.
The computer needs the tune to be able to take advantage of the headers and exhaust. You should end up with 40 more horsepower. It's not the headers,intake or exhaust.
:cheers:

The tuner I bought in 2014is no longer being produced. You can just get an intune I2 for GM vehicles. Shop around for the best price.
Check out the diablewtune website. It has some good info

I've used and done everything regarding tunes. I first tried hand held, canned tune devices like Diablosport. I finally ended up with HPT, completely learned and understood the tune process and then was able to evaluate what the canned tuners were doing in retrospect.

Much like the difference between when you first learned to add, then comparing that to learning calculus, the difference is that great. Understanding the complete tune process is not for everyone, of course, so the next BEST step is finding a real pro tuner in your area.

You didn't say where you're located. But likely there is a real tuner who knows how to correctly tune an LS engine close by. Tunes are typically in the $500 to $700 range. By the time you purchase a hand held unit like Diablosport I2 then deal with mail order tunes, etc. You'll spend pretty much the same money, but the results are going to be different.

I understand. I'm in Brooklyn NY area.really would want to tune it my self but always open for local tuners. I thought tuners come with preloaded tune modifications. I had BMW 335 before so tuner was pretty much straight forward I just had to pick in it what I had and it would take care of it.

How do you know you have less power? Have you took it to the track? Headers will add power but I can't feel it. I took .4 off my 1/4 mile time, but I couldn't "feel" any additional power.

It might be in your head

Go to your New York region forum. Ask their who is the best tuner and I am sure you will get many leads. You do not want a canned tune. When you can get a tune done on the car.
:cheers: