SLP LS1

Now I talked to my Uncle who knows a lot about cars... He thinks I'm running rich because the cats are off and the back 02 sensors also. I agree with him, but I'm still not quite sure. He said the headers blacken due to running rich, I thought the headers will blacken no matter what due to heat. Now I've heard that these LS1s will almost tune themselves to the best degree. My question to you is, do you think I should ge a tune or not?

This is all that I have done:
Blackwing lid
Donaldson Air Filter
MTI Throttle Body
Smooth Bellows
BG Ram Air
LS6 Intake Manifold
Kooks Headers w/ EGR
True Duals X-pipe without cats

I'm not going to do anything else to the car.

Billiumss

iTrader: (11)

It seems rich because you don't have CATs, plain and simple. CATs really do make a smell difference. I'm tired of the smell of my car and I'm putting CATs back on sooner than later.

You can get your VE & MAF tables retuned and that might help "some".

Rear O2 sensors don't control fueling.

StealthFormula

iTrader: (35)

I'd get a tune just because the car will run better and have more power especially since your done modding. I just had mine tuned and wow what a positive difference in the end.

SLP LS1

Well he's like "that may blacken my spark plugs and screw up the way the car is running." I revved it up a bit, I didn't see any black smoke come out. I think it's fine, I will eventually get a tune down the road though...

SLP LS1

I might do one more thing, maybe an underdrive pulley. But, I heard someone on here explaining that doesn't do a whole lot for A4s, doesn't really make sense to me... Any time you can relieve stress off of the engine with a smaller pulley should put out out some extra hp...

StealthFormula

iTrader: (35)

^^when you get a tune, some mods dont affect the tuning such as pulleys, lid etc. They wanna know if you have shorty/mid-length/full-length headers, cats or none, gears etc. And yea the pulley will give you horsepower but I think very little. My friend has them on his LT1 and his interior dash lights and stuff dim when at a light so I personally wouldnt get underdrive pullies.

FstBlkz28

iTrader: (13)

Headers tend to cause our cars to run rich. So with headers, and Offroad duals, I'm sure you probably are running alittle rich. No biggy, it wont hurt anything. But you'll probably pick up ~10hp with a tune, as well as some better gas mileage.

I gained 11hp/11tq when I had the car tuned after my headers were installed.