Printable View
New to HP Tuners......Installed a factory GM crate LS3 525 crate in 2003 Sierra. Using factory 6.0 intake for break in motor. Can't get motor to idle. Stock 6.0 injectors and MAP and injector settings. Original motor was 5.3. Computer untouched.....any advise on settings needed?
What did you do about the crank trigger differences?
The LS3 is a GEN 4 engine.
Is VATS turned off?
Are you talking LY6/L96 MAP sensor and injectors settings because the LS3 uses square port heads so I assume you are using the newer intake.
Yes motor is Gen 4. I've installed Lingenfelter crank trigger switch. I'm using stock MAP sensor from LM4. My intake is stock with cathedral port. I have adapter plates from square heads to cathedral intake. I plan to later install high ram intake with boost. Once motor is broken in.....Quote:
Originally Posted by 5FDP
Vats is turned off. Engine will not idle without me holding throttle at 1000rpm.
For sure that larger engine is going to need more base running airflow and likely more fuel too.
Get a wideband in the exhaust or take your best guesstimate based on what your fuel trims are saying.
I don't know what your plan for breaking in the engine is. 30 minutes of run time is about all I'd do. If you plan to drive it a few hundred miles you'll need to do a lot of tuning just to get it idle and behave on the road.
Thanks for the reply. As for break in..... I plan on running the truck for the summer and over the next winter I'll add a turbo kit I've purchased. I was hoping to get the truck to at least idle so it can be moved around. I read so much on the form on adjusting the MAP and fuel trim along with other trims I'm honestly overwhelmed what I should do......
Fair warning here too, being that they are stock LQ4 6.0 just injectors they will support maybe half the horsepower that this new engine can give out.
So you will have to get much larger ones if you want to drive this engine at anything past probably half throttle. And fuel pressure needs to be able to keep up as well. I believe stock LS3 camaro's run injectors in the low 40 lb/hr range so figure you'll want something around that or larger if you plan to drive it.
For now add some base running airflow, maybe 10-15% and try to see how the fueling is doing. It's probably going to be way lean.
And don't forget to update the cylinder volume for the new engine size, it makes it's airflow/fueling calculations based on this value.
Thanks again. I did purchase an upgraded fuel pump I've yet to install. I figured I would need upgraded injectors and was unclear which ones to purchase...….For some reason I read the 6L injectors were 52's? Not sure? When you talk about adding running airflow 10-15% is that the MAF settings?
This project will be a challenge.....lol
Which generation 6.0 are the injectors from?
GEN 3 would be from a LQ4 pre 2007, those are only 24lb/hr. GEN 4 would be from a LY6/L96. The later GEN 4 injectors can flow up to 50lb/hr if they are flex fuel injectors.
Base running airflow is the table name. It's in the idle tabs airflow settings.
The MAF airflow vs freq and the Primary VE table control fueling.
Hello.....the injectors are wrong. I was given wrong data. They are from a 2004 and are underrated for my application I know realize. I'm going to have to order a set.
Here is the log file for this engine running....
Attachment 98369
Fix your coolant temp sensor, it's going to overfuel when it's at -38 degrees.
Anyway to bypass?
Why not just install/fix the sensor? No idea how you'd get that circuit to duplicate what a ECT sensor can do.
That is a key factor is determining how much fuel the engine needs.
He says he can fix it. Broken clip.
Yes broken connector. Just replaced it.....difficult to find replacement....