16197427, BJYKOriginally Posted by brian617
16197427, BJYK
See if I can explain this and make sense lol. When connected to ADLD and streaming data click on the little icon looks similar to a clock "show data history tables" same one you use for BLM data. With the window open click on the drop down menu that generally has "idle VE BLM" Now you should see "off idle VE BLM, spark advance open throttle, then injector duty cycle''. For accurate maximum duty cycle you then want to click on the next drop down usually starts with "most recent sample" then click on "running maximum".
89 K1500 Scottsdale 5.7L 5spd 3:42 RamJet cam Dart iron TBI heads 427 PCM swap
95 C2500 Cheyenne 6.5L turbo diesel 4L80e 4:10 DB2-4911 Manual pump conversion 0411 PCM trans control 2Bar COS
05 Outback XT 2.5L turbo gas auto
I was unable to find this, but I ran another log using different ADX and XDF files and I was able to see it. Is there a way to tell which definition files I should be using? I used these this time, http://www.gearhead-efi.com/gearhead...ro%20RT%205.0/, the $0D ones. I ran a log with these and it shows my injector DC only at a max of 46% at higher RPM and WOT. Could this be right?
Possibly?
The stock $OD adx files were done with excellence along time ago and it was already set in Internet Stone how IDC% math was to be used. Now the Internet is off again forever, just like injector sizes... To bad it worked for MPFI and was only half of what was needed for TBI! There's a long thread around here somewhere when I found the problem but needed some serious math help to make sure my answer was correct. Here's what we came up with.
I'll attach a $0D .adx file with Inj DC% conversion set up correctly " (X*4*Y)/1200 " Now if you were running this for MPFI the conversion would be "(X*2*Y)/1200"1. TBI (X*4*Y)/1200
X= BPW and Y=Engine RPM.
TBI IDC (%) = [4 * IPW (ms) * RPM]/1200
2. MPFI (X*2*Y)/1200
X= BPW and Y=Engine RPM.
TBI IDC (%) = [2 * IPW (ms) * RPM]/1200
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
I'll give this a try. My confusion comes from changing fuel pressure and the Inj DC% doesn't change. I ran a log at 28 psi, and one at 21 psi, the Inj DC% went to a max of 46% on both runs. I would think it should change with less or more pressure. I will try this one and see what happens. Thanks Mark.
Did you increase the injector rating under scalars when you raised the fuel pressure? If not, the calculated duty cycle will be the same.
If you are running the same chip it will have the same BPWC and will not change unless your BLM reading is higher than 128 when you go into WOT.
ok, it is on the same chip. I got a chip from Mark, I'm not burning my own, yet. But I think I am soon going to, the more i am learning the more fun I am having. I am monkeying around with injectors and don't want to run out of fuel. I have aftermarket 7.4 injectors but i don't know what they flow, I am sending my 5.7 injectors out to get checked out. The truck seems to run better with smaller injectors at higher pressure than it does with the big injectors, but it could be the injectors. they are Napa replacements. They could be garbage so i want to get a set of GM 7.4 injectors and try them. The trucks runs OK with the Napa ones, but it smells gassy, and even in the exhaust it smells like fuel. I'm thinking the injectors aren't that great. I thought that it was showing the injectors use based on the demand and the adjustments it makes. I'm very green with this fuel injection but I'm learning fast thanks to you guys.
I was assuming based on where my BLM's were trending on the 7.4 injectors, and where they are now with the smaller injectors and more pressure, it's close. I did notice on the O2, it starts out at 925mv and slowing fades down to low to mid 800's. Is this ok to assume it could use more fuel at WOT or should that be left to a wide band o2 sensor for WOT info?
The narrowbands seem to be all over the board at WOT. I think my Express starts out around 825 and climbs to 950 at wide open throttle but my tune is setup to go richer after 10-15 seconds at WOT with catalyst overheat still active. Air/Fuel drops from 13.2 down to 12.0:1 at WOT and timing retards about 4-6*.
I have a set of 61lb injectors I am going to send out to get cleaned and checked...I swapped my Napa injectors back in so I can still play with the truck. They are supposed to be 80lb replacements, and at 14.7psi they should flow around 88.5 lb/hr but they just don't seem to have it like the little ones do. from around 4200rpm and up it feels flat with them. Running the smaller injectors at 22psi gives me 82.6 lb/hr, but it pulls better in upper rpm range. So once i get my 61lb injectors back, i am going to ditch the napa ones all together and try a set of GM 80lb injectors, that i know are good. is it normal for the bottom of the injector to be wet without starting the engine? with the fuel system primed, i have some fuel there, unless that is normal.
I am going to get the things i need to start burning chips, Mark got me very close and I am able to run my truck after TBIChips.com pretty much robbed me. But I like to tinker, and it seems from what I am seeing I will need to make changes to the tune when I play with fuel pressure and injectors and all that. I want to way thank to everyone that has given input so far, I'm learning a lot and I appreciate everything.
Does anyone know what can cause excessive knock counts? I get a few hundred when first starting the truck, and several at a shot for no good reason. It doesn't seem to give them to me under high rpm or anything like I would think. I just removed R44LTS plugs and am trying R42LTS plugs because I already had some. I read on another forum, Fast355 recommended them to someone who was asking questions about plugs and heat range. I usually like to use a colder plug on carb'ed engines, but maybe that doesn't work as well with fuel injected engines. The truck seems to run better strangely enough. I thought they may be too cold but what the heck. At an idle, the truck sounds better and it seems a little smoother. The tone out of the exhaust sounds different too, maybe because the engine doesn't shake as much or something, seems to be more distinct. I ran a datalog tonight, if anyone wouldhave some extra time to take a peak I'd appreciate it. The new plugs really changed the BLM and lowered the mV on the O2 readings at WOT versus previous runs. You can see the knock counts take off pretty high right away. I never hear any pinging or noise at all. This engine is build well and I always run premium fuel so I was hoping not to have any. I will run them for 250-500 miles and look at a few.
I wanted to order from moates.net, but they are closed this week. So I have to wait to get my stuff to burn chips, so I am again tinkering around.
Barry
knock during starting probably isn't knock, the way the knock filter works, it can think of it as such though.
1995 Chevrolet Monte Carlo LS 3100 + 4T60E
Ok, I finally did this, here is what I found. I guess this is too high?
BLG
It's higher than I would like to run at the upper RPM there, but not terrible.
The man who says something is impossible, is usually interrupted by the man doing it.
I agree. Now if that motor see's anymore RPM then that? Or if during more tuning you get some more spark advance in there? Well it will use more fuel... your short and need another 1-2 PSI fuel pressure. 90% is the amount I like to keep it under.
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
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