Twins with Twins, Anyone?

kidturbo

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Jul 21, 2010
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Got a couple more days of testing in before rain. All the post inj work went out the window. But learned a bunch... First post and pilots key off 100% off main mm3. Second by default, the low axis on post injection tables is 1700R by default. This can be changed outside of EFIlive. Also they typically only run Post2, which has no Quantity table by default.

So I get all sneaky and hard code lower Post2 RPM Axis. Find the post2 quantity tables and jacked that around a bit, thinking I got this figured out. Load tune with post2 tables enabled, take boat for a spin, logged it kicking post2 on for about 1second total out of 4 minutes.. WTF...

Ended up going back to old tune and by spinning the piss out of them, got up on plane several times. Actually reaching 67mph pretty easily. But then noticed Port engine cut out. Well it didn't cut it, it just dropped below 2000r, lost boost and wouldn't spool back up again. Even though boat was running 62mph... Was pretty cool to see just the other engine easily keeping up the boat speed.

Come back in, and get on phone with Mark for a bit to go over what hadn't worked with post inj. He recalls that maybe B0795 could be fuel limiting. So for shits an giggles I knocked 15% out of the rows below 2400, and ran it on the bench. The main mm3 increased from 60 with no boost, to 75mm3. I loaded changes and headed to boat ram before dark..

First video is from base tune we've been running since Feb. Second video, same tune with Lambda lowered. Response is much better down low. Now I need to fine tune and try to guess what calcylair value it believes it's running at without a MAF. Then clean things back up from there. Any starting points welcome.

Source: https://youtu.be/t9AOpPKCn5U



Source: https://youtu.be/kYaWjjHMuiU
 

kidturbo

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I'm learning why I don't like surface drives. Like driving on ice with bald tires. But after still fighting small issue on port engine, it can maintain plane, and accelerate with only one engine pushing it. Have some good data logs of port engine at 2000r no boost, starboard engine at 3500 and boat accelerating.

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2004LB7

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Dec 15, 2010
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Hay, you promised us rooster tails! I didn't see, not even one 😭

Maybe you can lower the B7095 table to it's lowest amount allowed and then adjust the PW or torque to limit smoke as needed. That way you know you won't be limited by that table. Or tune it based on EGT
 

kidturbo

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Hay, you promised us rooster tails! I didn't see, not even one

Maybe you can lower the B7095 table to it's lowest amount allowed and then adjust the PW or torque to limit smoke as needed. That way you know you won't be limited by that table. Or tune it based on EGT
I have a good video from today with roost. However I left the sound off, so gotta make your own engine noises.. Uploading now, slowly..

Lowering that sections of B0795 just 15% looks to have unlocked all the mm3 that main fuel table is requesting. As demonstrated in video below.. So we'll see how it does Sunday. I also happened to run accross the location of those axis tables you mentioned in other topic on B0795. A friend found them, not me.. I'm currently experimenting on the bench and will let ya know if stable.

Been fighting something weird issue that's pulling fuel out once in high gear at around 3200R, and only on Port engine. All the misfires are gone with the different ECM. Now out of the blue she just yanks the fuel down to around 40 mm3 for a couple seconds for no reason.. Then try to relight it at 60mph. Fun times indeed.. Will hash it out tomorrow.. Been up 40hrs so here is link to Rooster Tails. Should be done loading by now..


Source: https://youtu.be/s52kvcyPRjI
 
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kidturbo

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Believe I found my randomly missing fuel issue in Hi gear..

Currently both engines have TCM's connected, watching driveshaft speed. However, only Port engine has the VSS signal wire from the GPS unit connected. So my question is, which one of you jokers left this options turned on in my tune file ?? I'm Pissed!!

Ah wait a minute, I did say MY tune file didn't I... Yeah just never really think about checking the speed limiter tables in a boat.. 🚤

Best one of the week by far. She pulls that fuel out smooth a silk, and won't give it back until you slow down 5mph. Well this is a cool addition I guess.

Speed-Limit-Enable.jpg

Speed-Limit-Enable-Capture.jpg
 

Chevy1925

don't know sh!t about IFS
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Oct 21, 2009
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Believe I found my randomly missing fuel issue in Hi gear..

Currently both engines have TCM's connected, watching driveshaft speed. However, only Port engine has the VSS signal wire from the GPS unit connected. So my question is, which one of you jokers left this options turned on in my tune file ?? I'm Pissed!!

Ah wait a minute, I did say MY tune file didn't I... Yeah just never really think about checking the speed limiter tables in a boat..

Best one of the week by far. She pulls that fuel out smooth a silk, and won't give it back until you slow down 5mph. Well this is a cool addition I guess.

View attachment 104425

View attachment 104426

You had one job....
 

kidturbo

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My GM Tech buddy had just two jobs,, wire up both TCM's to the GPS with diode as discussed above. Had he wired up both units, the problem would have become evident more quickly moment both engines cut out at same time. So I'm blaming him.. LOL

When I jacked those PPM calibration numbers around in the TCM tune to match the GPS calibration, I never thought about the ECM reading the VSS output off the Bus.. Only wanted the speed info for data logging.. Seems GM uses that data for other purposes. On my first 67mph run, I'd forgot to turn on the TCM's so I have no recorded data that run. Ever since, fastest I can reach is 64mph with TCM on... To freaking funny...

ECM and TCM on bench so gonna verify the issue, AND calibrate the ECM to match.. OR maybe I'll just click that Disable button above and say the hell with it..
 

DAVe3283

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Why not both? Get the VSS on the databus accurate, if at all possible, then regardless disable the speed limiter.

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kidturbo

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That's what I'm playing with now.. The VSS according to TCM is spot on. Yesterday I logged VSS on ECM just to see what it sees, and that was nothing on the pid. So I didn't think it was active. But I learned last year playing with this on bench that the ECM either uses it's own VSS signal wire and tables, or it uses what it gets from TCM over the bus. I was trying to find the "bit" switch to makes it use the pin on ECM, haven't found that one yet.

Here's what's funny. The VSS kmh/mph reading out the TCM is spot on to true boat speed. And in table pic above, shows that ECM has speed limit set at 158kmh. I reaching no where near that speed yet. So ECM must be reading the actual pulses, and not the values after converted to speed VSS #..

Ran into something similar one time before on a truck. Friend had a 08 Southern Customs lifted. I loaded the ECM with file from a different truck, and then about 20 miles later it, it actually limped due to speed input mismatch error with TCM. Seems someone had calibrated both for the larger tires. When I changed the tune file, it became pissed off over the mismatch. Re-calibrated the ECM with data from old file, and it never popped up again..
 

kidturbo

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Got another run in Sunday, and stepped up to 76mph this time. Was pulling hard, then I looked back and saw this..

Left oil line AN reducer fitting to the turbo loose when I relocated the lines Saturday. This is example of why boats must have insulated or jacked exhaust pipes.. 5 quarts in under 30 seconds...

1d2c8cb2f1f358b3828f084bc6d92015.jpg


16a801a6782589aef605c651b5cd827b.jpg


077ef5449253f273d720ea86f7ccd3e2.jpg
 
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kidturbo

Piston Tester
Jul 21, 2010
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And both engines ran perfect with the TCMs unplugged. I killed the autocal linked to the ecms on the bench Saturday. So unable to modify the settings in them until I get it back. For now am going to data log TCMs pids on a separate canbus so as to not deal with the limiter issue.

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LBZ

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Ugh oil in a boat bilge sucks to clean up.
Meh. Hot water and a lot of dawn or Palmolive dish detergent seems to do the trick ok for me. When I change the oil in my boat I just dump it in the bilge and wash it out after. Takes about 5 gal of hot water. Better than trying to suck it out the dipstick hole.
 

2004LB7

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Dec 15, 2010
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Meh. Hot water and a lot of dawn or Palmolive dish detergent seems to do the trick ok for me. When I change the oil in my boat I just dump it in the bilge and wash it out after. Takes about 5 gal of hot water. Better than trying to suck it out the dipstick hole.

Where does this bilge oil go?