ls1 long tube headers base tune

Hello all, I've swapped 1 7/8th inch LT headers and a full exhaust onto my 2002 c5, and just want to throw a few quick tune changes at it for safety before my AEM wideband sensor gets here and I can really get elbows deep into it. The headers are the only engine modification so far, and I'm a beginning tuner in terms of engine performance(I use hptuners fairly frequently for basic engine swap stuff, transmission tuning, accessory tuning, engine diag stuff, that kind of thing). Just a quick pointer would be appreciated. Goat Rope Garage is my bread and butter right now, but I'm a bit overwhelmed with information to make much use of the videos.

Riley

The tune already on it is completely safe, headers alone isn't going to make it self destruct.

Just turn off anything that isn't needed anymore. Like possible rear o2 stuff, COT (cat over temp) and things like that.

I've disabled all the stupid rear 02 stuff and AIR system, along with the DTCs associated with it all. The worry comes from the classic horror story of someone adding a KN filter or something like that and instantly dropping 3 valves, pushing a piston into the hood, and bending 9 rods on their otherwise stock 2000 mile ls1. Can you point me in the direction of somewhere to learn a bit more about engine and wideband tuning?

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Originally Posted by rileymeekpierce

I've disabled all the stupid rear 02 stuff and AIR system, along with the DTCs associated with it all. The worry comes from the classic horror story of someone adding a KN filter or something like that and instantly dropping 3 valves, pushing a piston into the hood, and bending 9 rods on their otherwise stock 2000 mile ls1. Can you point me in the direction of somewhere to learn a bit more about engine and wideband tuning?

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Uh... K&N will at most cause deposits on the MAF wire. ESPECIALLY if/when they are over oiled. Next is if they are very close to the MAF they can alter the laminar/straight airflow over the sensor. That's why you don't want bends near the front or rear of the sensor. If you're running SD than no big deal.

Headers alone will definitely not hurt the car with a factory tune. Rode in many cars in my lifetime with bolt ons and factory tune that got beat on every night. Not ideal, I agree but isn't going to grenade the engine. C5 with headers would be a good learning car no doubt. Play with it is the best advice I can give you.

I think on my son's C5 we changed the proportional or integral settings or both a little bit to make it run, because after we put on the long tubes it wouldn't stay running. But if yours is running I wouldn't stress over it.

Quote:

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Originally Posted by rileymeekpierce

Hello all, I've swapped 1 7/8th inch LT headers and a full exhaust onto my 2002 c5, and just want to throw a few quick tune changes at it for safety before my AEM wideband sensor gets here and I can really get elbows deep into it. The headers are the only engine modification so far, and I'm a beginning tuner in terms of engine performance(I use hptuners fairly frequently for basic engine swap stuff, transmission tuning, accessory tuning, engine diag stuff, that kind of thing). Just a quick pointer would be appreciated. Goat Rope Garage is my bread and butter right now, but I'm a bit overwhelmed with information to make much use of the videos.

Riley

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With Just headers you'll be fine. One thing you can do is adjust the o2 sensor settings because they are positioned in a different location with long tubes. These numbers listed below are just base percentages and relatively accepted but if someone has a better more accurate number please add.

Under Fuel >oxygen sensor > proportional idle > airflow and lower it by .95 so enter .95 in the box and click the multiply.

Then right below that is integral delay airflow mode you can increase this by 1.2 so put 1.2 in the box and click multiply.

Just completed that. Turned off all the dtcs for the secondary O2 sensors, as they're now gone, and adjusted the O2 sensor settings.
Other than that, the tune is completely stock. Should I change fueling / spark at all to take advantage of the better flowing headers and exhaust? I want reliability, but I understand that more power means more engine wear. Not a huge issue though, am building an all forged ls1 that I plan to swap in when this stock one decides to go. That one's getting a newtech performance dyno tune, as they seem to be the go to tuners for the bay area. Thank you for the advice.