cammed 6.0 2005 Hummer knock retard

[Kevin Walker]

Hey all, new to this stuff, had a mail order tune done with my specs and the truck doesn't run well from 1700 to about 2300 under load. Looks like it's setting off the knock sensors and the eco is pulling timing causing it to be sluggish and sometimes hesitating. I went back and forth with Casey at mail order tune and he didn't do anything to better the situation so I have it with a local tuner now who is checking it out. I'm throwing it out here wondering if others have had this issue come up after camming, Somebody mentioned it may actually not be detonating but false readings by the knock sensors. I looked at the logs and it's definitely sensing like 6-8 on the knock sometimes. Maybe not on this log but others. I tried running 100 octane fuel for a half tank, seems to almost make it worse, thoughts??
25%inclineto60holdinissuearea.hplMailordertune1st tune 4.hpt
engine specs:
2005 6.0 automatic
headers, full dual exhaust, hi Flo cats
aftermarket cold air intake
heads were done with appropriate spring for cam
cam is Texas Speeds TS224R6114
Plugs are NGK TR6 gapped at .035
25%inclineto60holdinissuearea.hpl

[5FDP]

Is that the correct log you wanted to show? There was barely any knock in that specific data log.

The VE table for fueling is still stock, that will need a complete once over to get both the MAF and VE tuned. But before you did that you need larger injectors. The stock injectors don't have even close to enough headroom at full throttle for the mods on this engine. I bet it's pegging the injector duty cycle at 105-110% in the upper rpm's at full throttle.

I would also max out the burst knock table so that doesn't get in the way. And the timing advanced at part throttle is lower than factory. I'd probably start over with the timing and re-work it to fit that camshaft.

PS: That aftermarket cold air intake is more like a hot air intake. Even at speed the IAT's are 130 degrees. The stock airbox likely pulled in cooler air than that. I'd want 10-15 over ambient max for intake air temps and not 40-50+ degrees.

[Kevin Walker]

Wow thanks, that gives me some insight, I believe that first tune was his first shot, lemme attach tune#3 with a few pulls to entertain you
Mailordertune1st tune 4.hptWOTto90mph.hpl50%to70mph.hpl30%to70mph.hpl

[5FDP]

Kinda the same story here. There is more knock but things still need to be corrected.

The data logs are missing your injector data but we pretty much already know the injectors are far too small for the power this engine can make.

The intake temps are still really high, the one log was up around 150 degrees and only dropped to 130ish.

A wideband is really needed here as well. Without that there is no way to know what your air fuel ratio's are.

[Kevin Walker]

I'm glad you mentioned the injectors, I hadn't had that suggested yet. As this is a toy I don't drive it a ton. I did receive a final version from this joke tuner (version 5) but I think all he did was make some changes to the trans shifting. I have recently enlisted a local tuner who owns a hot rod dyne shop (unfortunately I'm all wheel drive) and he is looking everything over and I think he's gonna start from scratch for me. I was wondering about mechanical, he's going to look at the post recent data I gave him and let me know what's next. I'll mention your thought bout the injectors, he already may be thinking that too but he reset my laptop for me for all the data he wants to see including this you mentioned. I'd show you now but he has my laptop with the tunes on it. When I get it back early next week I'll revisit ya and let ya check out the latest tune from mailordertune.com that's I the truck now and my recent pulls when're he sees all the knock retard. This guy who was tuning for me was just throwing stuff out there without any real objective I think, Thanks!! Oh BTW when I was doing these pulls it was really hot, like 95 outside, that's probably why the temps were so high too but that's good info and I get it, the hotter the air going in, the more likely you are to detonate