Injectors Vs Fuel Pressure

[BLG355]

This is my latest .bin, remember it's $0E. Criticism constructive or destructive welcomed. Anyone welcomed to copy and paste any part you like!

I took the AE vs TPS difference! It's seems to work great. I had an issue with the trucking going into AE when idling, it would surge at an idle. Well, once it did it would puff black smoke and the idle would really surge. I got the idle settled down, but when cold I would bog majorly when trying to pull out from a stop. So I put the stock settings in and it got a better but it didn't feel quite right yet, I was sure if it went too far the other way and now it needed more, but then I tried yours, and it seems perfect. From cold to warmed up it has excellent throttle response.

I will look through it more this weekend, we have somewhat similar builds so maybe I can learn a little from it. Thanks!

[brian617]

Roadknee

I haven't tried to get too carried away with timing being a manual truck and simply just a old 4x4 work truck, plus with small chambers and flat tops it has a decent static compression. The combustion cambers just looked like Vortec copies. Hardest I've run the engine was about 5100rpm, its really quite a dog from 3500 up, probably caused by my stock intake. Anything past 4k and feels like you're pulling a parachute lol. Doesn't help with tall tires, 3:42 gears and crappy ratios in the Getrag 5 speed. Have the wideband fitted, great tool for tuning, specially AE stuff.

[brian617]

Barry

Seems with the small injectors at high pressure the AE tables actually have to be reduced. I also had to split the AE on time on the A/C clutch engage too. My truck did that same crazy AE surge at idle, almost as if it were over correcting. The wideband was priceless for tuning that AE stuff. My .Bin is far from perfect, but its the best my truck has ran since I built the engine 2 years ago. Haven't changed anything all summer, mainly just too busy with other projects, but at least now its reliable.

[BLG355]

Barry

Seems with the small injectors at high pressure the AE tables actually have to be reduced. I also had to split the AE on time on the A/C clutch engage too. My truck did that same crazy AE surge at idle, almost as if it were over correcting. The wideband was priceless for tuning that AE stuff. My .Bin is far from perfect, but its the best my truck has ran since I built the engine 2 years ago. Haven't changed anything all summer, mainly just too busy with other projects, but at least now its reliable.

Right now my truck runs fabulous, until I make another change then I think it is just that much better again. lol. I've been tuning for a few months and I have learned so much, every time I see someone post a BIN or a log I take a look. I've seriously considered several times giving up and then I get something figured out. I actually bought a 454 Vortec two weeks ago(complete engine less ecm and wiring harness and good 4x4 4l80e trans for $300), I also have a 454 tbi intake...I though about just ditching the small block and running a stock 454 setup. But the last week or so I have made several adjustments and I am learning what things are doing a little better.

I will post my BIN or at least my fuel tables later today to see if anyone has any suggestions...I am having issues getting a "smooth" fuel table. I am going to pull some plugs for inspection and recheck the header bolts(I love headers!). I am getting a huge spread at 40kpa and 800rpm. it shows as a spike on the graph. 35 and 45kpa it will be fine, but it shows it is always adding fuel at 40. What is acceptable as a range? the BLMs now go as low as 120 and up to 138. am i trying to be too perfect? the 40kpa at 800rpm really seems to change the idle, if I leave it set high the open loop idle is a little better, rich though.

Right now the truck runs and feels good so I am going to just keep at it and do some minor tweaks every couple of days, i'll put the big motor on the back burner for now.

BLG

[Roadknee]

Guys - What causes the ae to activate at idle, and what did you do to correct it? Thanks.

[Fast355]

Guys - What causes the ae to activate at idle, and what did you do to correct it? Thanks.

Could be MAP or possibly IAC AE

[BLG355]

Guys - What causes the ae to activate at idle, and what did you do to correct it? Thanks.

With mine, I am certainly sure it was because of the MAP signal. The idle would surge and the KPA would go and down, and there is a setting I saw that it will activate with so much change in KPA, and I could see on the log mine was definitely going over that. Once it did it once it would the AE would come on, which at that time it was way too much fuel and just make it surge worse. I was going to change this value but I figured I'd try to get it to stop surging and if it still did it, I'd change it. This is what it looks like in $0D.

MAP AE.JPG

[BLG355]

is it normal to have a spread in range like this?

Attachment 7633

BWT, I swapped out the roller rockers for roller tip rockers, knock counts went from 3000 to 30 over a 10 minute run. sometimes more, sometimes less, but overall, knock counts are way lower. Also, the surging is still present under no load conditions, but seems to have improved greatly while driving. Each time I run a log and mess with the fuel table, it seems to get better. I'm just not sure about some of the cells, I have such a large spread, I guess once I get it in the middle it will be ok.

BLG

I actually found how this is happening. When it idles, it is at 40kpa and 800 rpm. When coming to a stop, from like 18mph down, it hits 800rpm and 40kpa, but goes rich, BLM goes to 112 or so. So I guess there is a way to fix this, I'm just glad it wasn't all during idle and fluctuating that much. Maybe there is decal settings I can mess with.

BLG

[Roadknee]

Roadknee

its really quite a dog from 3500 up, probably caused by my stock intake. Anything past 4k and feels like you're pulling a parachute lol. Doesn't help with tall tires, 3:42 gears and crappy ratios in the Getrag 5 speed. Have the wideband fitted, great tool for tuning, specially AE stuff.

That is surprising. The ramjet 350 with that cam is rated 350 HP at 5200, although it does use 1.6 rockers. The HT383 peaks at 4600 rpm with that cam using a 4bbl carb. Both engines run vortec heads. I would have thought even flowing through the stock TBI your engine would make around 300 hp at 5,000 rpm. I have a vortec 350 in my shop now I'm building up for my 1995 K1500. I was considering the Ramjet cam, but your experience makes me think perhaps something like Barry is running might be better. Could you remind me what injectors you're running? Also, what's your injector duty cycle at 5,100 rpm WOT? Thanks.

[brian617]

That is surprising. The ramjet 350 with that cam is rated 350 HP at 5200, although it does use 1.6 rockers. The HT383 peaks at 4600 rpm with that cam using a 4bbl carb. Both engines run vortec heads. I would have thought even flowing through the stock TBI your engine would make around 300 hp at 5,000 rpm. I have a vortec 350 in my shop now I'm building up for my 1995 K1500. I was considering the Ramjet cam, but your experience makes me think perhaps something like Barry is running might be better. Could you remind me what injectors you're running? Also, what's your injector duty cycle at 5,100 rpm WOT? Thanks.

I doubt its the cams fault, 1.6 rockers and a better intake would probably be the key. I'm running 305 injectors @ 22psi for roughly 73pph. Last IDC% I can remember recording was around 75% WOT which makes me think I'm only making around 250-275hp.

[BLG355]

I am running stock 5.7 injectors at 22psi, so about 80-82lb. I set it up to shift a little higher, 5600. it doesn't really fall off, but it definitely is struggling a little. The cam is only good to 5200 I think. the KPA is around 88 at 5600rpm @ WOT. I did the lid flip before and it made zero difference, I guess it just needs more air if I decide to try 5500 rpm shift points.

IDC.JPG

[BLG355]

Here is the stuff I said I was going to post the other day and didn't. if anyone wants to take a look and give me some feed back I'd appreciate it. I didn't smooth the fuel tables as I should because it changes them right back pretty much every time I run it, so they I just sort of let them a little rough. The truck runs good, after about 1/4 to 1/2 throttle over 2500 rpm it feels a little weird like something is a tad off, but it seems to smooth out then. the fuel table is probably a mess and needs a makeover. But it idles good cold and drivability is good. If I tucked the ECM back in the dash and didn't tell someone it was a work in process, they probably wouldn't even notice by driving it. Since I used brian617 AE settings and they smoothed out al that stuff, I have been trying so many different things just to see what it does when I change it...I should take a break for a few days and just drive around with it instead of changing so much...but it is so much fun!

[Fast355]

I doubt its the cams fault, 1.6 rockers and a better intake would probably be the key. I'm running 305 injectors @ 22psi for roughly 73pph. Last IDC% I can remember recording was around 75% WOT which makes me think I'm only making around 250-275hp.

The 395 marine cam is barely bigger than a stock L31 cam. Stock L31 witha few bolt ons and headers with a good tune is around 280-300 hp. The LT1 cammed L31 in the 99 Suburban is making roughly 350-375 hp worth of fuel disappear. Running 8 x 23.9 lb/hr spider injectors at 92-93% duty cycle at 5,400.

[Roadknee]

The 395 marine cam is barely bigger than a stock L31 cam. Stock L31 witha few bolt ons and headers with a good tune is around 280-300 hp.

Is that 280-300 HP with TBI or Vortec MPFI?

[Fast355]

Is that 280-300 HP with TBI or Vortec MPFI?

With either really...At that power level neither really restricts anything if tuned properly. The vortec CSFI and dual plane TBI intake both fall off sharply around 5,500.