general setup questions but not anything i see reference to

[Joshua11]

hopefully these are not stupid first i am a 30 year mechanic ( in a shop everyday since i was 16, 47 now) i am working on a 99 chevy 6.0 ls that was an iron head until a week ago) did rings, bearings, heads and small torquer cam 511 lift 202/202 dur and 111+1. also when i did this i stuck a 0411 ecm from a 2001 Silverado in it. when comparing files from 99 to the 01 it shows firing order in different places (same order but different locations) does this matter it seems to runs albeit adding 5-6 in stft at an idle when maf unplugged and pulls fuel when maf is connected. but before i make any corrections the injector setup is quite different also like minimum injector pulse width in 01 0.760 across the range but 99 was 1.505 till 2000 rpm but then tapering down to 0.684 after that. the default injector is setup in the same manor. has anyone seen this? is this because there is some difference in the injector? and should i put those values in the 01 ecm. just don't want to adjust anything if the base calculations are wrong and make things harder or have to start over. anyway hope these aren't stupid questions and someone knows the answer. thanks for any help

[5FDP]

I didn't look it up but if the injector part number is different from 1999 to 2001, I could see that being a reason for the minor differences.

The firing order stuff doesn't matter, just leave that be. Also remember that the MAF has the IAT sensor in it, so what it does for the fueling can't really be trusted because the IAT goes to -40 with the MAF unplugged.

A camshaft is going to change the fueling around idle no matter what. You'll have to do minor adjustments to the base running airflow and alter the fueling in the MAF/VE table around idle to clean it up.

[blindsquirrel]

If a stock tune file has injector flow rate & offset tables with all the columns the same, then that file came from something with a vacuum-referenced fuel pressure regulator. If both those tables are sloped, it came from one with a 'returnless'/non-referenced fuel system. Even if the injectors are the same part number, if the regulator type is different the injector data will be different.

[Joshua11]

it has a return line and vacuum reg on rail unplugged goes up 8-10 psi

[Joshua11]

is there a more recommended injector i could get down the road that would work better for my combo. engine is in a 2000 k2500 obs crew cab weighs 7000+ used 5.3 heads with the cam i described it pulls car hauler and wanted more bottom end it never sees over 5000 rpm

[blindsquirrel]

Can't tell you if you need different injectors without knowing which ones you have now.

[Joshua11]

i wouldn't think so without tuning and watching your duty cycle to make sure its not too high, but ive heard of people putting bigger injectors in stock trucks and them running stronger but ive never tried it i don't know. ive done carbs for years worked in old school speed shop for a while but on my own now and am hoping to learn how to modify with fuel injection. lol

[Joshua11]

21.5 i believe, too dark now will try to get the number tomorrow after i get a diff done for a customer in the morning.

[5FDP]

If they are indeed only 21lb/hr, get bigger ones for sure.

8.1 injectors are 31lb/hr and gen3 flex injectors are 33lb/hr.

[blindsquirrel]

With the vacuum line removed, check the pressure in the rail with a mechanical gauge. The base pressure will make a difference in how you use the injector data and what the new injectors came from. The 33lb L59 injectors are only 33lb because those trucks (and the data in their tune files) have a lower base pressure than the non-flex fuel trucks (51psi vs 58psi). Not a problem to get the data set up right once all the variables are known.

[Joshua11]

i know I will need to change the connectors to an EV6. Will they fit my 6.0 stock rails? and/or will I need any other modifications as far as fitment?

[blindsquirrel]

innjector dimensions.jpg

[Joshua11]

so looks like they are taller and i would need a rail spacer to raise the rail, other than that and the plug I don't see anything. the top Oring difference only 0.001 difference so nothing there

[blindsquirrel]

Injectors do not normally hit a hard stop at the bottom, it would probably just put the lower o-ring a little farther down in the hole. If it didn't fit as-is it wouldn't take much of a spacer to raise the rail, like only a single flat washer per bolt.

[2xLS1]

You don't go into any details on why you swapped the PCM to the 01 0411 or what calibration is in it. Give me some details on that and I may have an answer for you.

[Joshua11]

I heard they were more reliable than the 99 model as far as not frying while flashing, plus a speed shop did a base tune 10 yrs. ago and I wanted to start fresh. Its a has a 2001 Silverado 2500 6.0 4l80e factory tune in it. Which I thought would be the same programming but didn't match the iron head programming at all, even though they both had return lines and 21.5 lb injectors. Even the trans tune is different, and they are both 4l80e/MT1 transmissions. When I pulled the engine 2 wks. ago (330,000 miles) to refresh it I put a cam and heads on it as well, calculated 10.6:1 comp. The truck is super heavy and wanted more bottom end power. I have a couple other engines I'm working on for going fast , lol. I thought I would learn a bit on this one (tuning fuel injection) as it's a pretty mild build. Anyways, any help is greatly appreciated.

[2xLS1]

This probably won't be popular here but I've been doing this a long time.
First are you sure you know what you have? Only the 99 4.8L and 5.3L used the 21.8 lb injector. 99 6.0L are rated at 24.8 and the 01 6.0L are rated 25.2. I have a lot of those stock files for both of those years and all the different engine sizes. That is what they all have for injectors. The cam you are using is not that big (202/202). It is only 11/10 degrees different duration than the 99 6.0L cam (191/190) and 6/-5 degrees different than the 01+ 6.0L cam (196/207). The 99 6.0L injectors are 24.8 and the 01 6.0L injectors are 25.2. So they are a different part # but they are close enough that in your application and use it won’t make any difference. The other injector data is also slightly different but it won’t matter for your use. You can look at GM stock calibrations for 01-02 F-Bodies and 01-04 Vettes that use the exact same injectors (same part numbers) and you will find more differences in the data used by GM calibration engineers for those different vehicles with the same injectors than the differences in the 99 vs 01 6.0L injector data. Don’t let the injector police here make you unnecessarily spend money on bigger injectors you don’t need for your application. Also there is nothing wrong with the 99 4896 PCMs. I think you might be confusing them with the 97-98 Vette and 98 F-body PMNs that have a bad reputation. But I've never had a problem programming those either. If you really think the 0411 hardware is better (debatable) you can always write entire the 99 calibration to the 01 PCM with a Write Entire.

[2xLS1]

Here are a couple of stock 99 and 01 60 files for comparison.

[Joshua11]

Thanks just didn't know how the 9.5 to 10.6 compression jump or the cam was going to affect the fuel injection system. I had some small knock show up in first three drives (1-2 deg), but I took some of the data from 99 and put it in the 01 computer and it hasn't come back yet. Still seems to pull fuel at one end and add at the other rpms, but I've had a rough go tranny wise and haven't been able to collect much, if any useable data, had the tranny rebuilt about six weeks ago but now if I go 10 miles and shut the truck off it won't go back in gear and the direct drive starts screaming. I've tried calling the guy for three weeks now and no answer, so I bought a used one and am going to R&R over the weekend. so hopefully I can get some data soon. I just want it to run as good as it can till I can get my other engine finished.

[Joshua11]

0k went out to truck and got the injector numbers off the truck. Apparently the salvage yard paperwork was off too (only by a year} and the engine is a 2000 it was complete manifold, injectors etc..... the injector number is 25320288 and is specific to 2000 only. when I looked them up (injector planet) they say 20.5 lb./hr. not sure if that rating is correct but I don't know the best source for that info.