Hi all,
Tuning a 2016 sierra 5.3, BTR stg 2 cam with 4 deg limiter, speed engineering long tube headers no cats, 6.2 factory intake and matching throttle body and AEM cold air intake. Rear o2s not fitted currently. Have set up a decent base tune, starts runs and idles great. Still needs maf, vve, timing to be tuned.
Two issues i believe i have are, what setting need to be adjusted for no cats? I have COT disabled, but i believe there is a cat warm up (Light off) that happens on cold starts, have searched through the tune file and cant find what im looking for. It will occasionally back fire out the exhaust during the first 30 seconds of running at idle which i suspect is the cat light off?.
The other issue is what tables need adjusting for the front o2s being further down the exhaust?
Thanks very much.