need help on for a start up and idle tune on a lq4

[[email protected]]

i have a lq4 with a btr stage 4 cam and 60 lb injectors that was swapped into a 69 camaro running a th400 trans deleted vats for initial start up just trying to get some advice to get motor idiling decent and fueling right and not run so rich


2000 lq4 6,0 truck motor
317 heads
tbss intake
60 lb injectors
1 3/4 long tube headers
90 mm tb
btr stage 4 cam 244/230 .553/.553
standalone gm harness
factory 6.0 truck pcm with vats deleted

6.0 stock tune.hpt

[5FDP]

One of my favorites things to read is just the injector size with nothing about who's injectors they are.

And you kinda need to input that data into the tune, doesn't really work with stock injector data. Thus the running terribly.


Raise your idle way up with a huge camshaft like this, it's not going to be happy at 550rpm. Try like 800rpm when warm.

Needs more base running airflow too, probably add 15-20% just to start.

Turn off EVERYTHING that isn't being used, rear o2 sensors, EGR, cat codes, disable all transmission codes, evap codes etc etc etc.


There is so much more than that, would take forever to type the rest out. This is an older computer/OS too, I'd highly suggest applying the speed density OS and ditching the MAF sensor to make tuning easy.

[Ben Charles]

That’s a 224 not a 244… but if you need help with remote tuning let me know!!
Love 69 Camaros

[[email protected]]

Well that's the thing about the injectors idk what they are all I got is the poundage that's why I'm asking any help or advice of what would be proper for this engine setup to optimize it like changing to smaller or certain injectors

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And yes Ben I slipped up it is a 224 not 244 my bad

[blindsquirrel]

12613411 - 5.3L LMG, 38lb @ 58psi, $51/ea
12613412 - 6.0L L96, 51lb @ 58psi, $21/ea

Please note that if you just go to ebay or Amazon and search those numbers, you will find hundreds and hundreds of listings of cheap Chinese fakes that do not use the same data as what you find in stock tune files - so you'd be no better off than you are right now.

[[email protected]]

So the 12613412 injectors would work for this setup blindsquirrel?

[blindsquirrel]

Either part number should be a direct fit to a TBSS/Gen4 truck intake, fuel rails, and electrical connectors; I don't know what you're using other than "tbss intake" which can mean different things to different people. Making them fit, physically, is a lot easier than trying to use injectors that have no data.