08 silverado 5.3 sloppy stage 2 cam; professional tuners pls review files

truck is pretty much stock, but it does have a port matched intake manifold, polished 243 heads with upgraded valve springs, new LS7 lifters and pushrods. the cam specs are 228/230 with 112 LSA. its got the stock 4L60e trans and stock converter right now but i do plan to get a circle d 2800 stall converter soon and try to do any upgrades i can to my trans. im pretty new at tuning and ive been working on getting this truck to run decent. this is the first data log that ive recorded that ive been pretty pleased with. the truck seemed to do great at WOT and its nice and healthy at cruising in town speeds too. attached is my current tune file and most recent log. if anyone with some professional knowledge could please review the log and tune file and let me know if anything seems to need attention that would be great. i appreciate any input. thank you all.

What power adder? If there's no power adder, how is MAP reading 120kPa?

This is still a LY5? Using stock LY5 injectors? Either injectors have been changed and injector data not updated right, or injector data was changed without changing injectors.

2008 LY5 MAP sensor should have linear 94.43/offset 10.34. Your 128.20/-.030 is for the later LS3-style MAP (also used on trucks, but only '09-up).

Top: 94.43/10.34, bottom: 128.20/-.030
Attachment 128987

the map sensor on my intake manifold is absolutely the TOP sensor in the above pic. there are no power adders. injectors are the stock injectors (as far as i know) but I'm the 5th owner of the truck so i guess there is a possibility that the injectors could be different. what would the correct injector data need to be? this is exactly why i am asking for input from professionals. i would like to learn how to get this tune dialed in for the best performance possible. i do not currently have a wideband, although i just ordered a PLX wideband kit that i will be installing the minute it arrives. any information on how i can get the correct injector data would be greatly appreciated

i have been having hard startups sometimes, like it wants to stumble and die 5 seconds after startup. eventually it does stay running, but could incorrect map sensor offset be the cause of that? i just replaced the MAP with a brand new sensor earlier this evening. it was an Advance Auto part but it seems to be working better than my old MAP

The correct injector data depends on what the injectors actually are. They should have part numbers on them. Don't just fling some stock data at it and hope it's right, there's no way to know whether just the injectors or just the data was changed (or maybe both, with both done wrong) by somebody before you.

Go grab all (or several) 2008 Silverado/Sierra 5.3 files in the repository, look through them until you find one with 'J' as the 8th VIN digit. That's a LY5.

And, any tuning done before now will have to be re-done, since that was based on having the wrong MAP & injector data.

Attachment 128992

Attachment 128993


these are the only values for the injectors that i found different on a stock LY5 tune vs my current. ive changed the values in my current tune to the stock ly5 values though.

Leave Desoot off. I would've changed only Injector Flow Rate, after I'd confirmed the injectors are stock LY5 and not some other random whatever. The other critical injector data was still stock, the other stuff is not injector data.

Injector Flow Rate, Min Injector Pulse, Offset vs Press vs IGNV, Short Pulse Adder are what's related to the physical injector hardware.

okay, i usually have my Injector flow rate set at 22kpa for the minimum and i see alot of tunes with the Min injector pulse set at 0.750 as opposed to the factory setting of 0.797, is this better or should i leave my injector pulse at .797? what would you recommend that i do to the Offset vs Press vs IGNV table to improve my tune? and also what should i set my short pulse adder to? thanks. i will verify my injectors first thing tomorrow

Injector data is injector data, it is not a tuning aid. It is like MAP linear/offset, or cylinder volume. It's not something you fiddle until it runs good. If it needs changing then it wasn't correct in the first place.

got it. thanks. i usually compare my current (at the time) tune to a tune with similar cam specs. what id like to learn how to make adjustments to are things like EQ ratios, spark table adjustments, trans tuning, fueling, ETC adjustments (if there are any) i know i need a wideband to get my tune dialed in right for my specific vehicle, but i want to learn anything i can that involves writing performance tunes and fuel economy tunes

new log file to review as well as tune revision. input is greatly appreciated. is there any way i can get the truck to stop surging when im at a red light for example? it shakes the truck so much youll spill your drink if your not careful lol

Something like https://forum.hptuners.com/showthrea...e-tuning-guide ?

You're not logging near enough stuff for starters. I'll attach one of my random channel configs. Download - right click - show in folder - save - go to where hpt is in your computer - go into scanner - channels - paste here then you can open it from the channel area of your scanner. I would also start by adding 10% minimum to your entire MAF curve before you drive it anymore as it's very lean. You'll want to tune in your VE and MAF both before you go any further or destroy anything. For the idle - a lot will smooth out with correct fueling, but you can also shift your adaptive spark tables to the right 1 cell to help.

If they are the stock LY5 injectors they should be 19421333/12580681. Those flow 29.4 @ 400kPa, NOT 40.8. An LY5 will have 'J' as the 8th digit.

PLEASE tell us what the numbers are printed on the side of your actual injectors.

Do you have cats installed, or no? Downstream O2 codes are disabled (and for some damn reason, about half of the upstream O2 codes as well), but catalyst codes are not... Post O2/Catalyst tests are also still on.

this is the only numbers i can see on one of my injectors at this moment without pulling the rail. can you ID this injector? and yes, i do still have cats but i plan to remove them in the near future.

Quote:

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Originally Posted by blindsquirrel

If they are the stock LY5 injectors they should be 19421333/12580681. Those flow 29.4 @ 400kPa

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Attachment 129027

I re-enabled the upstream O2 DTCs, left the downstreams alone, also did not change any of the catalyst stuff. I suspect you disabled the MAP codes from when it had the wrong linear/offset settings in it? That's... not a good process to use, those codes were trying to tell you there was a problem, and there was.

Quote:

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Originally Posted by blindsquirrel

Top: 94.43/10.34, bottom: 128.20/-.030
Attachment 128987

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Heads up.. there are some random clip in style map sensors with the 128.20 scaling and they seem to be sprinkled in 2008-2009's only. A part number is the only way i'd trust I have one or the other.