Check the plugs and do a compression test while you're in there.
Also look at: IAT vs ambient temp, EGT off cylinders 7 or 8, Boost at compressor vs boost in manifold.

*turbo since 2002*

 

Ok. So cat is off and the truck is a stable 11 lbs on my gauge and my map sensor shows 26 so that’s 11 lbs.
It’s still detonating at 4800 rpm on the street according to the logs at only 8 degrees of timing.
Im thinking this cam is creating too much cylinder pressure at peak torque causing the need for the low
timing in that area.
Also, this truck doesn’t push fuel
pressure up to 60psi. It will only raise it to 53psi which is why my duty cycle is so high.

 

You're connecting dots that shouldn't be connected. If you reduce spark advance to decrease cylinder pressure and reduce detonation, then cylinder pressure due to spark advance isn't the problem. I'd be looking at other sources of noise from the knock sensors...like those injectors that should be in the OEM LSA blower manifold and nothing else. The 10 degree conical injection angle offset is a recipe for a poorly homogenized mixture, which itself is a source of preignition and often detonation.

 

That’s a good point. I didn’t think about it that way. Also didn’t think the injectors had that much to do with it since they flowed enough. I figured something was wrong with the truck.
so you really think detonation can be caused by the injectors design?
Interesting....

 

We also could hear the detonation. My
wideband was showing 11.9-12.2 afr When commanding 11.4. That’s also a problem.
On the dyno we also saw the puff of smoke
from the exhaust at the time of the detonation.

 

Yeah, problems from poor mixing in the cylinder can match the symptoms of an engine (typically older designs) with poor chamber swirl and quench or LSPI in newer direct injected stuff. I can't say with 100% certainty that injectors are your problem but I'd definitely never run those in anything but the LSA or LS9 blower manifold. While mixture lean pockets can cause some detonation hell, so can unexpected overall leanness...so yeah get that figured out as well. I'd also post a pic of the actual spark plugs for reference.

 

I’ll get some pics of the plugs. With 98% duty cycle on the injectors, something is off in there. I’ll get some 80’s in there and see what changes.
Thanks for the help. I’ll update soon

 

All this back and forth and no log or tune for us to look over.

Your issues are not the injectors. Guys have pushed 100+% duty cycle without detonation. Not advised albeit.

 

I don’t have a way to log with this truck.
sorry
ill try and get time but my buddy that has hptuners is busy.

what would you like to see in a log sir?

 

The injector issue I mentioned wasn't due to duty cycle but the injection angle. Modern port injected stuff doesn't have an issue with high sustained duty cycle because they are not low impedance injectors and aren't going to overheat.