Knock e38 camaro ss 15

Hi

This car was a drag race car and is tuned for nitrous. Now, it is a daily commuter for work. The changes on the engine are a cam, cold heat range plugs and other mods. Pretty board there, sorry. I did not get into details and I should have. I know plugs and cam he did say. The issues as described by my customer are as follows:

1. 72-86 degrees, 91 octane, 3% grade(hill), 1500+ rpm pings on light throttle, improves with more throttle.

2. 100+ degrees, 91 octane, level(road), barely pings at 1500+ rpm light throttle only.

3. Definitely pings worse at cooler ambient temperature

4. 85 degrees, with 50% octane boost and 91, level road, 1500+ rpm, cruise control set, pings with ac, no ping w/o ac.

5. With cruise set up 3% grade, after 5 sec of pinging, I back off the throttle, thought the knock sensor would have retarded the timing in that time span.

The tuner who performed the work said this:

Last time I saw you I pulled a couple of degrees of timing in problem areas and made the intake air temp retard more agressive for the hotter temp because you said it was just when it starter to get hot. This should have had it covered in all cases because it would be pulling a couple degrees of the timing in those areas no matter what the temp, but it got hot it would pull another degree or two on top of that.

The nitrous tune only had timing pulled out above 3000 rpm at wot, nowhere else so loading that tune now would actually be more timing in it compared to the last tune I just put in there in those problem areas.

I opened the tune file. Yes, it was not locked. I was lucky. There is a lot of work done. I download a stock file from hpt site and use it as compare file. I wanted to change the iat vs spark airmass table to stock and pull timing from the main high octane table. I did not hook up my wb sensor yet and I will to verify lamda in the problem area. What do you think. Am I in the right direction? Any help I sincerely appreciate.

Thank you

It sounds like your solution is sound. It's unusual in my experience to have the engine knock at colder IAT and not at hotter IATs. I generally find the stock iat vs spark airmass table is pretty good so reverting to that and working on your main spark table is a sound starting point. I have no idea why you'd be getting knock based on the air con though.