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Headers and high flowcats installed with NPP exhaust and had a question. Like the C7s, is there a fuse or fuses that you can pull to keep the baffles open at all times?
I have been driving around and no check engine light so far . Sound in my opinion is amazing. Power increase without a tune is good. We gained almost exactly 21 rwhp but the good thing is, there were gains across the entire band.
There will be a full write up but so far this seems to be a good way for some decent gains without requiring a tune.
If I'm not mistaken, the C8 tune stays in closed loop, so at WOT the fuel trims continue to adjust. So, if true, the C8 must have a wideband. The question is how much will the fuel trims adjust before a DTC and tune is required?
Last edited by Mike's LS3; Apr 19, 2020 at 01:17 PM.
If I'm not mistaken, the C8 tune stays in closed loop, so at WOT the fuel trims continue to adjust. So, if true, the C8 must have a wideband. The question is how much will the fuel trims adjust before a DTC and tune is required?
How many miles on the car since the install? Thought cel light after self test? High flow cats nowadays pick up 10 -20rwhp alone depending on power level so much more efficient. There's more to be had with a tune.
How many miles on the car since the install? Thought cel light after self test? High flow cats nowadays pick up 10 -20rwhp alone depending on power level so much more efficient. There's more to be had with a tune.
Congrats
Not sure about that. The car can self-tune now with the wideband right? If they have a desired AFR at all conditions then the car should self-tune for bolt-ons. Sure there's some power from leaning it out, but that's not safe long-term.
Not sure about that. The car can self-tune now with the wideband right? If they have a desired AFR at all conditions then the car should self-tune for bolt-ons. Sure there's some power from leaning it out, but that's not safe long-term.
When I've put headers on my cars, in addition A/F adjustments, the timing also gets changed, both at WOT and part throttle.
When I've put headers on my cars, in addition A/F adjustments, the timing also gets changed, both at WOT and part throttle.
Usually getting more aggressive with the timing isn't explicitly due to the headers, it's just being able to tune more aggressively than the OEM "cover it all" tune. Not saying the car won't benefit from custom tuning, but the car won't go lean at WOT with basic mods now that it has a wideband.
Usually getting more aggressive with the timing isn't explicitly due to the headers, it's just being able to tune more aggressively than the OEM "cover it all" tune. Not saying the car won't benefit from custom tuning, but the car won't go lean at WOT with basic mods now that it has a wideband.
Headers can help in adding timing due to the reduction in EGT's. It will be interesting to see how far the C8 will adjust A/F ratio at WOT.
^^^ Agree, assuming the car remains in closed loop at WOT and has a LTRIM cell if should be pretty safe for bolt-on mods.
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OP: Can you post the dyno graph?
Sure, here is stock ( mine dynoed very low) vs. the install (blue). It was still climbing also until the end run so I do think there is more there once we run the car more.
Sure, here is stock ( mine dynoed very low) vs. the install (blue). It was still climbing also until the end run so I do think there is more there once we run the car more.
Nice gains. Awesome that it has a wide band sensor, be great to see how lean/rich it kept it.
Headers and high flow cats installed
