5.3 to 6.0 (HP93) Swap, Low Performance

[tinindian77]

I apologize for the book (below). I wanted to provide some background and as much info as I can to help you help me. Lack of info seems to be the biggest issue when I read other posts.

I am new to tuning, but have tried to do as much research as I can to prevent costly errors.
My issue is that I really don?t feel that this engine is running as strong as it should. The builder advertises 460HP/470TQ at the flywheel when used with the given bolt-ons: (headers, dual exh, throttle body, intake, 36lb Injectors, and a tune). I get it that I will lose a considerable amount of power in the drivetrain, but I can?t even break the tires on takeoff unless I?m on gravel. In addition, listening to the engine it just sounds labored and lethargic.

Here is what I have:
2005 Avalanche 4WD, originally equipped with the 5.3 Flex Fuel engine. I have swapped in a LQ4 built by ATK engines, model ?HP93?. This engine has a mild cam (Howards PN: 190235-14) and 9.5:1 compression.
Engine URL: https://www.high-performance-engines...ine-p/hp93.htm
Along with the engine, I installed a cold air induction, shorty headers and true dual exhaust with a balance tube, new O2 sensors at position 1, and new knock sensors and harness. I always run 92-93 octane and rarely see any counts from my knock sensors (when I?m checking).
The drive-by-wire throttle body as well as intake and injectors are stock.
The Transmission is a built 4L60E with stock converter, and gears are stock 3:42.

Here is what I have checked:
Fuel pressure holds steady at 58psi (no regulator on fuel rail). I ran an injector balance test and everything was within OEM spec according to the service manual. Very little if any variation between injectors.
My cats are still installed, so I checked back pressure and that was zero.
I drove the truck with a fuel pressure gauge connected, and it held the 58 psi steadily without drops.
From what I have read, these injectors should be good for around 35lb. Keeping in mind that they have around 250K miles on them, they seem to be keeping up when comparing the Wideband and VE table.
Compared my wideband from both sides of the engine and they were very similar.

Tuning:
I started by copying tables from a stock 6.0 repository in order to get a base.
To my best of knowledge I have disabled the MAF and am running in SD mode. Using a wideband, I have tuned the VE table to the point where I feel I?m splitting hairs. I feel that cells above 3500RPM may need some additional fine tuning, but I believe they are close.
The timing tables were copied from an LQ9 that had been tuned by Texas Speed. This gave me quite a bit of additional power in the seat of my pants. If I back off of the timing, I can definitely feel it, but I have been hesitant to add more in thinking that I shouldn?t need more with this engine. Plus, I?ve yet to find a good (safe) way to tune the timing tables so I?m a bit hesitant.

Comparison:
This is actually the second engine that I have run in this truck. The first one dropped a valve and wiped out a piston and rod. It was covered under warranty, and I would like to think that tuning had no effect here. I was not easy on the first engine, but I don?t think that it was abused either. I was a GM tech for around 15 years, and I have seen where engines were abused. But? I?ll never claim to know everything, which leads me to post this question in the first place.
Both engines were the same part number and both seem to run and behave pretty much the same.
One thing that I can point out is that it seemed to run better without the cold air induction. I've tuned the VE since then, but I remember a noticeable difference in how it pulled immediately after installing.
It currently seems to pull harder when I gradually accelerate as opposed to just stomping the pedal. Like low timing advance...
I really feel like I?m missing something in this tune. But maybe I?m expecting too much from a mostly stock engine trying to launch 3 tons?

I?ve attached my current tune along with a couple of scans from this tune.
Thanks in advance for any thoughts/suggestions.

9.56.hpt 9.56.hpl 9.56.1.hpl

[5FDP]

You left a lot of the delays for PE as factory.

Lower the pedal enable to 65%. Lower the enable torque to 50%, raise the MAP kpa enable to 80kpa. Remove the 0.8 second time delay and set the RPM delay to 1,200-1,500rpm. Put the enrichment ramp in rate to 1.000

I'm not sure I'd run 30 degrees on timing at full throttle though. Maybe 25-27 degrees.

For speed density set the dynamic airflow switch over to 7,000+ rpm and not 1,000rpm like you have it now. Normally you want to remove your MAF channels when VE tuning. And make sure to smooth the table after each change, you have some dips and spikes in there right now which shouldn't be there.

Also burst knock is still active and that can make abrupt timing pulls when you stab the throttle.

See if some of those settings help.

[tinindian77]

I really appreciate you looking at this. I have opened my tune and started on the changes. However, for the life of me I cannot find what you are referring to on the "set the dynamic airflow switch over to 7,000+ rpm and not 1,000rpm like you have it now". My intent was to shut off the MAF, but I have had a feeling that it was interfering.
Can you elaborate more on where you found this setting?

I have not yet interpolated my VE table, so yea I'm sure it's all over the place.

On disabling the burst knock, would you suggest zeroing out the Enable Delta Cyl Air under?

[5FDP]

Under the airflow tab there is a dynamic airflow tab, on the left it should be called dynamic airflow high rpm disable.

Burst knock is the opposite of what you typed. Setting it to zero would leave it on. Setting it to 8.0 turns it off.

[tinindian77]

I made the changes that you suggested and definitely can tell a difference. Runs smoother and seems to pull a little harder in the mid-range.
Even still, from a stop I don't even come close to chirping a tire. Do you suppose in this case that the cam is pushing the powerband high enough for the gears?
I don't expect to do a wheel stand by any means, but with traction control turned off in the tune, I anticipated a little more with the advertised hp numbers.
Going forward, I'm going to continue to smooth my VE table. I'm also posting my tune after making the changes as you suggested. If you see anything else that may be out of line, please do let me know.

9.57_ForumAssisted.hpt

Thanks again!

[5FDP]

Remember that there is a high and low octane table for timing. Speed density only uses the low octane table while tuning. So it's still at the 30 degrees of timing and then if you left it that way when returned to MAF/VE non speed density it would try to add timing instead of taking it away when a knock event happened. It would go for 27 commanded and try to go to 30 and make it possibly knock worse. Make the high match the low for now but when speed density tuning is done remove like 4-5 degrees from the entire low table so it can use the knock learn factor to pick timing between the two tables if there was knock.


What tires are on this truck?

Really grippy tires and the fact that the avalanche has like a 5 link suspension from the factory, it makes them plant the tires and just move out. I'm sure if you had 4.10's and a nice stall converter it would rip right up into the power band and burn some rubber.

[tinindian77]

I did not know that the SD looked only at the low octane table. I assumed (based on what I had read somewhere else) that it gravitated to the appropriate table after fill-up. I will copy over.
The tires are standard stock style 17" AT's.
And don't get me wrong, I don't necessarily want to burn rubber. I'm just wondering why hooking up isn't a problem. LOL.