Help with 120lb injectors please
Thread Starter
Joined: Nov 2004
Posts: 1,273
Likes: 3
From: Rochester, NY
Help with 120lb injectors please Car is a turbo 5.3L with 2 Bosch 044s, boost referenced regulator, 120lb low imp injectors with Versafueler.
VE table was tuned pretty well into the 150kpa range. I only tuned it to that boost level on the 60lb injectors as that's where we were running out of fuel. Right now car is at 4 bar base on E85.
I changed the injector flow rate vs kpa table in HPTuners for the new 120s and didn't change anything else. Idle is good, PE is fine. The problem is a lean hole as soon as you crack the throttle. This makes it almost undriveable.
I've done some reading, and it's looking like I may have to dabble with the short pluse adder. I had to play with that a bit in my GTO to get my 160s to idle on the 370ci. I've also read about the transient tables but my GTO doesn't use those so I've never played with them. I also had to go to 3 bar base with the help of NicD in order to get my 160s running decent.
Will hopefully figure it out on my own this week, just looking for suggestions to maybe hurry this process along. One thing I did notice is that the STFTs are wayyy negative now and it used to be pretty close. I'm thinking I may have just missed something with the injectors.
Car is OLSD with STFTs enabled.
Thanks!
Adam
VE table was tuned pretty well into the 150kpa range. I only tuned it to that boost level on the 60lb injectors as that's where we were running out of fuel. Right now car is at 4 bar base on E85.
I changed the injector flow rate vs kpa table in HPTuners for the new 120s and didn't change anything else. Idle is good, PE is fine. The problem is a lean hole as soon as you crack the throttle. This makes it almost undriveable.
I've done some reading, and it's looking like I may have to dabble with the short pluse adder. I had to play with that a bit in my GTO to get my 160s to idle on the 370ci. I've also read about the transient tables but my GTO doesn't use those so I've never played with them. I also had to go to 3 bar base with the help of NicD in order to get my 160s running decent.
Will hopefully figure it out on my own this week, just looking for suggestions to maybe hurry this process along. One thing I did notice is that the STFTs are wayyy negative now and it used to be pretty close. I'm thinking I may have just missed something with the injectors.
Car is OLSD with STFTs enabled.
Thanks!
Adam
You should not have to increase the transient fueling for the new injectors to avoid a lean spot. Sounds to me like the voltage offset and short pulse adder table needs some work, this is assuming it was tuned with the correct injector data from before. Those injectors with the driver box are sloppy even though they tend to have a lower voltage offset than normal 60s.
Thread Starter
Joined: Nov 2004
Posts: 1,273
Likes: 3
From: Rochester, NY
That's where I will start then. That makes sense.
The following information was supplied with these injectors but I have not used it at all:
"I measured the dead time of the 120s on my flow bench:
volt ms
14.5 0.70
14 0.74
13 0.81
12 0.90
11 0.96
10 1.07
9 1.23
8 1.45"
Is this useful?
Thanks for your help as always Nic. You've really helped me out a lot in the past and I truly appreciate it!
The following information was supplied with these injectors but I have not used it at all:
"I measured the dead time of the 120s on my flow bench:
volt ms
14.5 0.70
14 0.74
13 0.81
12 0.90
11 0.96
10 1.07
9 1.23
8 1.45"
Is this useful?
Thanks for your help as always Nic. You've really helped me out a lot in the past and I truly appreciate it!
Thread Starter
Joined: Nov 2004
Posts: 1,273
Likes: 3
From: Rochester, NY
Played with the short pulse adder, limit, offset table, ve table, etc. Everything follows like it should, changes all make sense and do as commanded. The lean spot was unaffected by anything I changed. Any ideas?
I've attached a log. You can see when I tap the throttle, the MAP raises slightly and then you can see the narrowbands go lean as hell as the INJ MS goes up from like 1.9 to 2.4, then it clears up. I do have a wideband in the car that I'm using as well but it's not being logged. Changing short pulse adders, VE in this region, etc did nothing to change this lean spike.
I'm lost.
I've attached a log. You can see when I tap the throttle, the MAP raises slightly and then you can see the narrowbands go lean as hell as the INJ MS goes up from like 1.9 to 2.4, then it clears up. I do have a wideband in the car that I'm using as well but it's not being logged. Changing short pulse adders, VE in this region, etc did nothing to change this lean spike.
I'm lost.
Unfortunately without knowing if they are using a peak/hold driver like yours on their bench to get that info I can't say if it's useful or not. From my findings the offset seems to be a bit less than that and closer to the SD 60s using a versafueler peak/hold box on the LS1 PCM... but this is trying to remember from many years ago when I used those same injectors on my car without incident.
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Played with the short pulse adder, limit, offset table, ve table, etc. Everything follows like it should, changes all make sense and do as commanded. The lean spot was unaffected by anything I changed. Any ideas?
I've attached a log. You can see when I tap the throttle, the MAP raises slightly and then you can see the narrowbands go lean as hell as the INJ MS goes up from like 1.9 to 2.4, then it clears up. I do have a wideband in the car that I'm using as well but it's not being logged. Changing short pulse adders, VE in this region, etc did nothing to change this lean spike.
I'm lost.
I've attached a log. You can see when I tap the throttle, the MAP raises slightly and then you can see the narrowbands go lean as hell as the INJ MS goes up from like 1.9 to 2.4, then it clears up. I do have a wideband in the car that I'm using as well but it's not being logged. Changing short pulse adders, VE in this region, etc did nothing to change this lean spike.
I'm lost.
Does it have this same behavior at higher RPMs under a bit more load (cruise ~65-70 kpa then give it some gas)?
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Verdad Gallardo Thread Starter
Joined: Nov 2004
Posts: 1,273
Likes: 3
From: Rochester, NY
Yes it seems to act the same no matter the load/rpm. I will have to verify again tomorrow, but as of right now I'm leaning to a mechanical problem as well.
I think the next plan is to jumper the driver box and reinstall the 60s and flash the old tune. That will at least eliminate the wiring/map/everything besides box/injectors/tune.
Thanks again
I think the next plan is to jumper the driver box and reinstall the 60s and flash the old tune. That will at least eliminate the wiring/map/everything besides box/injectors/tune.
Thanks again
