I never had a problem with this until I went to my new GT2-3 cam. You know how you get some boost in overdrive when going up a big hill or just passing someone without hammering it? It's just 1 to 3 psi usually. Now it has a big dead spot right there and I also get KR. What should the timing be around here?

Or should I be checking something else in the tune?

I'd rather not post the whole tune on here, as it's a work in progress. But the VE and MAF have been tuned and are spot on. The wideband on the screen is showing .3 leaner than what the truck actually is.

 

Explain your reasoning for not posting the whole tune again....that would make it a lot easier to help as well as the actual log file. And fixing the wideband pid is very easy, I suggest doing that so you won't have to guess any more

 

Because I don't want people digging through it and bashing me for unrelated stuff. I got the previous cam running perfectly, but it has been probably 2 years and I forgot some of the methods I used. I don't even remember where I got this timing table, but it worked great on the TR220 cam. There was no KR at all and this one has huge spikes.

I attached the log. It is with the 2.23 beta if it matters.

 

We're not here to bash you for unrelated stuff. And I'm sure if that even happened, the mods wouldn't have any of it.

 

Thanks smoke. I just added the log if you are interested in looking. I didn't hear the knock, but there is just little-to-no power when I was giving it 35% throttle at this specific RPM/air mass combination.

I was thinking about changing the plugs, but the truck runs great at most other RPMs so I'm thinking it's something in the tune.

 

Even though your wideband is reporting .3 leaner than it actually is, high 14s is still too lean for boost. Doesn't explain why your timing begins to drop before KR sets in, though. Your IATs didn't fluctuate a single degree for the entire 46 second duration of the log. Even if you're just barely getting into boost, there should be some variation. Everything plugged in after the cam swap...?

 

I had a WOT log that I saved right after that, and the IATs crept up to 90. It was just very cool out last night and a short log. I wasn't sure if I needed the full PE at such low RPMs, but I will tweak it if you think I should.

The timing is dropping as the cylinder air mass is increasing, so everything there matches up. I'm just not sure why the thing is so unresponsive.

I am still kind of a noob to this stuff. With my first cam, I got really lucky and everything just fell together after a few logs. Thanks for the pointers.

 

It doesn't need full PE, but as soon as you tip into PE it should begin to richen up just a little bit. Most tables I've seen are in the 1.100 range from 0-1500 and begin ramping up from there. You should log burst knock to see if thats pulling timing before KR sets in.

 

I will explain what i think is going on in a few min when i am back to a computer. 2 questions first. You still running a maf and have you adjusted the burst kr any?

 

A couple of things, first off i don't see command AFR in the logs... Maybe i missed it, but i aways log that bad boy...

I would adjust your commanded AFR table for rows greater than 90kpa to something lower than 14.68... This way it will be in open loop and rely on your MAF/VE table for fueling....

The dead spot is from your timing... According to your screen shots you would have been commanding 12* of timing at that particular "dead spot", whcih was dropped to 4* due to the KR.... More than likely it feels different than the previous cam is because the new cam breathes deeper, meaning more grams/s... You will need to adjust to your timing table to compensate...

the dip before the kr kicked in was probably due to burst KR. you were probably exceeding the threshold which in stock form is pretty low... What burst KR does is pull timing on a sudden change in grams/sec, to "try" and prevent KR....



Now with all that said, you are probably geting KR due to a untuned fueling condition, without being able to see your tune it is hard to tell... I suggest making the AFR change like i mentioned above and retune those low rpm high grams/sec areas....