I think a few data logs and leaning the lower MAP areas of the VE table will straighten that out. If not, you can increase the AFR's in the Open Loop Idle Lean limit vs. Temp table.Originally Posted by BLG355
I think a few data logs and leaning the lower MAP areas of the VE table will straighten that out. If not, you can increase the AFR's in the Open Loop Idle Lean limit vs. Temp table.
i'm not used to an injector flowrate value being called a BPC..... that is normally reserved for the ECMs that have a table of 0-255 values referenced against % of airflow is EGR.
1995 Chevrolet Monte Carlo LS 3100 + 4T60E
Well, I ran the engine after readjusting the valves and still have glowing manifolds. I switched back to the R44LTS plugs, still have glowing manifolds. It pulls 20" of vacuum at idle, can't find and leaks in anything. I'm really stumped. I'm attaching a log that show how much spark knock I get in a short time (10 min). I did run another chip, It was brian617's timing table, stock everything except the injector flow was changed to match the actual flow. With this, cruising around, there is no visible glow, but if I run it even half hard, the manifolds glow. I am reluctant to try the new distributor, but I think that has to be the next thing I try.
I did manage to get a good look at them on a dark back road, they aren't glowing right off the head, but down more toward the log after the elbow off the exhaust port. and the whole log glows, front to back. if anyone gets a chance to look at the data log, I really appreciate it. I don't understand how I can have 3,000 knock count and it isn't showing it's pulling timing, unless I'm looking at it wrong. Thanks again.
BLG
The knock retard doesn't bother me much. There are over 7000 lines of data in that log and less than 60 with knock retard; the highest being less than 2 degrees. The rate of increase of knock counts must meet a threshold in order to activate knock retard. So you can have counts without retard.
What is odd is that the spark advance reported in the log does not match Brian's timing table. The actual is retarded several degrees, and varies by amount throughout the table. For example 2800 rpm and near 50 MAP in your log is 25 degrees, yet Brian's table has 35 degrees. Might be worth checking with a timing light at various rpms to verify whether actual timing and the log matches up.
if you read the disclaimers at the top of the xdf file the adx needs editing to suit base timing to display properly
I'm sorry I wasn't very clear about the log. I put the starter chip I got from Mark back in to run the log and see how it went because it runs pretty much plain awesome with that chip...then later i tried the other setup to see if it would settle down. the log is on the chip from mark which is different timing than Brian617's table.
I did check the timing versus what computer is showing, but i didn't get real involved but i will check it at varying RPMs. But when cold it is more advanced and all just like on the computer.
BLG
Hello Everyone. I decided, against my better judgment, to try an experiment, and it has me very confused. I took the BIN I had than had pretty much zero glow while drive easily around town, which consists of Brian617 timing tables, and the stock tune with the fuel flow adjusted to match actual flow. I then proceeded to advance the base timing 10 degrees(not in the tune though)...and go for a drive. So when I am actually showing 35 on the computer, I am actually at 45. Anyways, here is a log, it didn't pull timing like I thought it would(I thought for sure it would have all kinds of knock retard, it is also very responsive. So once the sun goes down I am going to take it for a burn and see if I have glowing manifolds again, if not I am going to throw the good chip in and try that and see if they glow then. I can't believe it would need all this timing. Does the ignition module control any of this stuff, like if it was going bad or anything? I only know then to totally kaput when they go bad.
BLG
With the NAPA module its hard to say what latency your'e getting. Read this thread http://www.gearhead-efi.com/Fuel-Inj...-timing-curves
The 369 GM module will match the latency setting in the $OD and $OE bins.
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
Well, I got tired of waiting until it got dark, I pulled the old distributor out and out a new GM one in. I did have an old module here that is a 369, the one in the distributor was actually a GM module too, but it is the new part number for the 369 module. The new distributor module has part numbers that don't do anything.
So, I set the timing back to zero with new distributor, still glowing. I advanced it 10 again, no glow at cruise and light load, WOT I have a glow although not as bad. I did notice since I turned the fuel pressure back, the O2 is dips into the 840's MV range at WOT, where as before I was well into 930-940MV. So the first thing that comes to my mine is now it's lean, although I know I shouldn't trust NBO2 for WOT data. I am amazed that it didn't pull more timing away. I though for sure it would be pulling timing all over the place, but it didn't. I did verify again with a light, when revving the engine, the computer matches my light for advance.
I noticed it's only going into the high 60's for the injector duty cycle, if I lower the flow ratings by a few pounds, will it make the open loop richer at WOT?
here is the log, if anyone wants to take a look at it, I appreciate it. I'm still using the same ADX that has been posted earlier. With this log, the base timing is advanced 10 degrees, but not in the BIN, so it's 10+ what it is showing. I would love to find something wrong with this thing. I think I am going to relax for a night or two and clear my mind and start digging into it this weekend. There has to be something wrong somewhere. My big injectors come back from Mr. Injector tomorrow, so I will put them back in and maybe pull the intake and look for cracks or something. I have a Bosch O2 on it, I am even thinking about replacing it with a Denso or Delco. Have a good night and thanks for everyone's help thus far. You guys are all great. Thanks.
BLG
You can still look at accurate Spark Advance by going to that value and changing the conversion to X * 0.351563 + 10.000000 see the end where it add's 10?
Looking at your log your light Cruise Spark Advance is at 40* +...
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
I decided to change the O2 sensor, I am getting somewhat different readings than I was before. I had a new Bosch in, but took it out and put in a AC Delco sensor which looks very much like a Denso. I didn't have any glowing cruising around, at my usual first stop to check there was absolutely no glow where there always was before, well none that I could see. But at WOT I still do, but it isn't near at bright tonight. But I noticed with the new O2, I am now very low 800mv, dipping to the high 700mv range on the O2 at WOT. At some points it was as low as 746mv. After a good hard pull, say from like 45 to 80mph, once I let out of the throttle, the mV linger in the 400-500 area for a few seconds before dropping off to pretty much zero for the next 8-10 seconds as I come to a stop...would this be lean enough to get the manifolds glowing or is this something that is normal. I haven't noticed it before if it is normal.
Has anyone dealt with the throttle body being worn at the shaft? I have no play, but when I wen crazy with the brake clean the idle dropped way off when I sprayed around the TPS sensor. I'm not sure if it was from a vacuum leak or that I could have gotten some break clean in the throttle body, I had the lid off. It kept raining tonight so I am going to dive into that more tomorrow. I did manage to pull almost another full inch of vacuum at an idle be making a block off plate for between the EGR and the intake. I think I had a leaky valve. It seemed to help some but I got something else going on I think.
I attached a pic, Bosch left, AC Delco on the right.
May just be the nature of the beast. I know for a fact the stock manifolds on my 5.7 Vortec Express would glow after an 80-90 mph sustained highway cruise with the stock engine and tune. The pipes between the manifolds and muffler were always bluish purple from the heat and I had a cracked manifold at 57k.
Also worth mentioning my Titan has a rediculous amount of exhaust heat. It has discolored the lower grade stainless T-409 IIRC from the manifold cat through the mufflers to the exhaust tips and even discolored my T-304 exhaust tips an ugly brown color.
Higher HP engines dump proportionally more exhaust heat out of them. The manifolds and pipes will get hot. My old 83 G20 had my doug thorley tri-y headers glowing so brightly one night towing a large enclosed trailer with a car inside that I had a Texas Highway Patrol car pull me over thinking I was on fire.
Last edited by Fast355; 06-14-2014 at 07:27 AM.
Well stop doing this! Your running lean, the NB is not accurate but it's enough to tell you that your lean at WOT. So either adjust your PE fueling so the numbers get back into the .9xx or plan on melting a hole in a piston...
I have tested O2 sensor new from the box and there is a slight difference in where they think Stoich is. I did four sets IIRC... I'll look up my results and they ran from .97 to 1.04 lambda with nothing else changed, so this can be expected.
Yes you could have a vacuum leak at the blade! Some more testing and it could show quite a bit on one side... is it your O2 side? Is the other side leaking too? I better safer way is a propane torch like for soldering. Watch that your not feeding the IAC inlet...
Or like Fast says it just may be your new built hot motor and some cheap exhaust manifolds designed for half the HP?
Either way all the BLM numbers have been well within O2 correction, some of the spark tables have been OK and some have been to much. You still get glow? So back to a couple things to check and maybe it's time for a good set of Ceramic Coated thick headers to get the heat out the exhaust pipe.
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
I thought I heard it change on both sides, I will try to propane today with the air cleaner on so I don't feed the IAC. I have heard of them leaking but I have extremely limited experience with it. I know people bush them when there is slop but mine seemed nice and tight, but seeming tight and pulling vacuum past are two different things so I will dive into it more.
BLG
This is the first performance engine I ever build that didn't have headers. As good as this thing runs I should just upgrade. I started it with the O2 sensor out to try to feel any backpressure, wish I had a gauge. to me, it felt excessive, but with a dynomax super turbo, they do create backpressure. Everything runs so well, maybe it's just too restricted, I have the stock crap y-pipe in there yet too. that should probably go no matter what I do.
BLG
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