Dirty-Maxx after 600hp build regrets

[reese600]

not without numbers like piston protrusion and hg thickness but thats kind of a mute point as the dynamic compression ratio isnt really going to give you the answers you are looking for.

Ok, another problem.
With this thing running like a turd, I figured I'd hook my Snap On scanner up and see what the injector balance rates looked like. The injectors were tested at S&S, i have the sheets, but i have to figure this out. Of course, the scanner won't connect. I can use my EFI Live Autocal and it reads and clears codes, but the Snap On scanner just says can't communicate. So I check the pinout on the OBD2 port, and I have 12.5V on pin 16, pins 4 and 5.have ground, pin 6 CAN Hi has 2.9V and pin 14 CAN Lo has 2.2V and the resistance between pins 6 and 14 is 63.3 ohms. Anyone have a clue why my Snap On scanner won't communicate so I can check balance rates?

 

[2004LB7]

no too familiar with snap on scanners, bit they do need to have the details 9f the vehicle entered correctly to communicate

also, your Autocal should be able to read the balance rates

 

[1FastBrick]

Ok, another problem.
With this thing running like a turd, I figured I'd hook my Snap On scanner up and see what the injector balance rates looked like. The injectors were tested at S&S, i have the sheets, but i have to figure this out. Of course, the scanner won't connect. I can use my EFI Live Autocal and it reads and clears codes, but the Snap On scanner just says can't communicate. So I check the pinout on the OBD2 port, and I have 12.5V on pin 16, pins 4 and 5.have ground, pin 6 CAN Hi has 2.9V and pin 14 CAN Lo has 2.2V and the resistance between pins 6 and 14 is 63.3 ohms. Anyone have a clue why my Snap On scanner won't communicate so I can check balance rates?

Which Snap On Scanner? and what revision of software?

 

[reese600]

Which Snap On Scanner? and what revision of software?

it is an Apollo-D9 software version 21.2

 

[1FastBrick]

it is an Apollo-D9 software version 21.2

Ok, so it's newer. Assuming you have checked it on other vehicles to make sure it's functioning properly.

The other reason I asked is because I had identified a bug in the older version of software where it was not correctly Identifying and LBZ on a 2007 model. I believe it was rectified 2 updates later.

Unfortunately I have not updated mine in a few years with the pandemic and all.

 

[reese600]

Ok, so it's newer. Assuming you have checked it on other vehicles to make sure it's functioning properly.

The other reason I asked is because I had identified a bug in the older version of software where it was not correctly Identifying and LBZ on a 2007 model. I believe it was rectified 2 updates later.

Unfortunately I have not updated mine in a few years with the pandemic and all.

yup, tried it on the wife's 2019 Equinox, and it connected instantly.

 

[reese600]

Another tidbit to share, this is a 07 LBZ engine that I built and put in my 09 truck using the LMM harness and ECM, all tuning has been done for the LMM. The engine has all of the sensors on it from the LBZ, except for the mass airflow sensor, I had to use the LMM one. I keep wondering if there is an LBZ sensor that still plugs into the LMM harness, but gives different readings than the LMM sensor would.

 

[1FastBrick]

yup, tried it on the wife's 2019 Equinox, and it connected instantly.

Any chance you spoke with there tech support about this issue?

Another tidbit to share, this is a 07 LBZ engine that I built and put in my 09 truck using the LMM harness and ECM, all tuning has been done for the LMM. The engine has all of the sensors on it from the LBZ, except for the mass airflow sensor, I had to use the LMM one. I keep wondering if there is an LBZ sensor that still plugs into the LMM harness, but gives different readings than the LMM sensor would.

Interesting.... that's above my pay grade. However, I am curious. My understanding was that from an ECU standpoint they were similar but that doesn't mean that something didn't change as far as the values it reads between the engine models.

 

[Chevy1925]

Your issue with the snap on scanner isnt new, sadly. i know of a few shops that have had an issue similar to yours or having data being read waaaaay off from what it should be. They would wind up using a different scanner and have no issues.

 

[reese600]

not without numbers like piston protrusion and hg thickness but thats kind of a mute point as the dynamic compression ratio isnt really going to give you the answers you are looking for.

I do recall that i used GM grade "C" head gaskets. I am going to do a compression test as soon as the adapter for my Snap-On gauge comes in for a D-Max. If the numbers are low, I guess i will have to take the heads off and check protrusion.
I'm attaching a few pics of when i had the bottom end up on #1 prior to putting the heads on, just on the outside chance that maybe someone with more experience with these engines can spot something wrong. Do i want to tear it back down, obviously not, but if it is what I have to do to fix this engine, then that is what I will do.