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Now for a nice tune.


Dudeland

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So I ran some errands this morning.  I decided to put on the data logger and here is what I got.  You can download the sniper EFI tool (windows only) at the following link. The timing should be accurate to within a degree or so.  I am running a 123 so I can change the advance and vac curves.   This is all I know, I need to learn from here. 

 

 

https://documents.holley.com/techlibrary_sniper1.1.3installer.zip

 

 

 

 

Regards

 

 

 

 

 

 

sniper_0003.dl

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Installed it and took a brief look, seems to be working and I like the software, but we'll want more data to really get a feel for things.  My first piece of advice is that when you take a datalog, you want to get good long stretches of 'common' driving conditions.  So get a few good long idle sessions (this log has one or two, so that's OK), then you want some cruising at different but constant RPMs.  So cruise for a while at 2500, 3500, and 5000 RPM for say 30 full seconds each.  Then you want some full throttle measurements, so run through the low gears a few times with full throttle up to redline. Lastly, again run up through the rev range but at part throttle, like you'd accelerate in traffic but keep the throttle constant and let it rev all the way up.

Biggest thing I see from this log is that the acceleration enrichment needs some work; you're getting big lean spikes whenever you're rolling on or off the throttle.  Does the sniper autotune accel enrichment too and/or are there manual settings to play with?

Oh, and probably the best/simplest way that I like to view a datalog is as follows:

Start with RPM, MAP, and AFR graphs.  This lets you see the engine's 'response' (AFR) at a given speed (RPM) and load (MAP).  This gives the best overview, then you can add/subtract stuff to look at specifics in small areas.

Lastly, I'm definitely going to recommend changing your ignition timing a bit; 2.7 degrees at idle is kinda ridiculously low; you should be somewhere in the teens.  36-37 degrees all in looks pretty good though.  And generally you can run *more* advance at low throttle and *less* at higher load, and I think you have that a bit the other way around.  Hope this helps!

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Ok so overall it is feeling ok, but sitting at an idle. every once in a while it will just drop.   I see that the timing will drop to 0 degrees.  Not sure why.  You can see this sort of crazy ivan happening.  It is in segment 1414 to 2202.  Can anyone make sense of it?  It is almost like the dizzy is shutting off, or the MSD.   The signal goes from the dizzy to the MSD, then out of the MSD into the Sniper. 

 

I had a great datalog ready, but I was so excited that I shut off the car before I stopped the log, which means it didn't save it.  Attached is what was captured during the random drops. 

 

Will do more on my drive this afternoon. 

 

 

 

 

Sniper_0010.dlz

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Ok so my alternator just went for a shit.  Soooo I will have to get that fixed tomorrow. My fault, the connection got loose, connection fatigued and the wire broke loose of the connector. 

 

 

 

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I saw there's some discussion online that the MSD may overheat parts of the 123. I wonder if that  is happening.

 

Cheers,

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So what is actually controlling timing then, the 123 or the Sniper ECU? Clearly the Sniper *thinks* the timing is dropping to zero, but we need to figure out if it ACTUALLY is.  If sniper is commanding the timing, then it probably is, and we need to fix it in the tune.  However if the 123 is controlling the timing and just sending the signal to the Sniper, then it's more likely an issue with the signal.  Either way, I would suggest you break out the old fashioned timing light and see if you can compare actual timing (with the light) against the logged timing.  While you do that experiment, let me review the Sniper documentation again and see if I can determine all the options we have to work with.

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Ok, so reread things, and sadly it seems that the Sniper units cannot accept a toothed wheel input for crank signal and then directly control a coil.  I suspect this is because they're trying to get most people to pop for their dual sync distributor, and that's fine for most of their customers with 'Merican engines, but it's not quite optimal either.  The drawback is that it all cases, it takes the crank signal from the distributor (not the actual crankshaft), which means that any lash/tolerance in the whole valve train (timing chain stretch, sprocket wear, cam to dizzy gear lash, etc.) causes some inaccuracy.  In any case, for someone with a basically stock M10 ignition I'd recommend the MSD route with locking down the dizzy and letting Sniper control the timing.  However since you already HAVE the 123, you don't really have much to gain from this and instead I'd say just use the MSD to send the RPM signal out to Sniper but let the 123 continue to actually control timing (page 24, the Ignition Box Tach Output - No Timing Control setup).  You get to program you own advance curve either way, but having the Sniper do it would be a 'longer' chain (123 - MSD - Sniper - MSD - Coil vs. 123 - MSD - Coil) which just gives more possibilities for error, at least the way I see it.

@Holley Tech, please feel free to correct me if any of my understanding/assumptions are incorrect, and I'll just say I think it would be worth considering adding crank wheel input and direct coil control options in future versions! Granted I'm a biased fan of wasted spark setups, but I'm sure I'm not the only one!

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On 11/15/2018 at 4:16 PM, ray_ said:

I saw there's some discussion online that the MSD may overheat parts of the 123. I wonder if that  is happening.

 

Cheers,

I suspect that it was running out of juice, and the MSD was cutting out.   I never had a problem before with the 123.  The current draw on the 123 is around 2A coming from the MSD. The limit I think is 3A, so I am safely in the zone,  There is an issue using a MSD with Pertronix. If you leave the ignition on too long, you can burn them out (or so people say) 

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18 hours ago, AustrianVespaGuy said:

So what is actually controlling timing then, the 123 or the Sniper ECU? Clearly the Sniper *thinks* the timing is dropping to zero, but we need to figure out if it ACTUALLY is.  If sniper is commanding the timing, then it probably is, and we need to fix it in the tune.  However if the 123 is controlling the timing and just sending the signal to the Sniper, then it's more likely an issue with the signal.  Either way, I would suggest you break out the old fashioned timing light and see if you can compare actual timing (with the light) against the logged timing.  While you do that experiment, let me review the Sniper documentation again and see if I can determine all the options we have to work with.

So the 123 is setting the timing.  It triggers the MSD,  then the MSD sends a signal to the sniper.  My voltage was dropping well below the limit for the MSD,  I don't fully understand why, but when the voltage to the MSD drops they get super wonky. 

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17 hours ago, AustrianVespaGuy said:

Ok, so reread things, and sadly it seems that the Sniper units cannot accept a toothed wheel input for crank signal and then directly control a coil.  I suspect this is because they're trying to get most people to pop for their dual sync distributor, and that's fine for most of their customers with 'Merican engines, but it's not quite optimal either.  The drawback is that it all cases, it takes the crank signal from the distributor (not the actual crankshaft), which means that any lash/tolerance in the whole valve train (timing chain stretch, sprocket wear, cam to dizzy gear lash, etc.) causes some inaccuracy.  In any case, for someone with a basically stock M10 ignition I'd recommend the MSD route with locking down the dizzy and letting Sniper control the timing.  However since you already HAVE the 123, you don't really have much to gain from this and instead I'd say just use the MSD to send the RPM signal out to Sniper but let the 123 continue to actually control timing (page 24, the Ignition Box Tach Output - No Timing Control setup).  You get to program you own advance curve either way, but having the Sniper do it would be a 'longer' chain (123 - MSD - Sniper - MSD - Coil vs. 123 - MSD - Coil) which just gives more possibilities for error, at least the way I see it.

@Holley Tech, please feel free to correct me if any of my understanding/assumptions are incorrect, and I'll just say I think it would be worth considering adding crank wheel input and direct coil control options in future versions! Granted I'm a biased fan of wasted spark setups, but I'm sure I'm not the only one!

4

 

Agreed and that is the way I did it, I took the shorter option.   What kind of signal does the dual sync generate?  It states it has a hall effect, but that doesn't nail it down much.  Does it hall effect and output a 5v wave.   I don't think that is how it works, not to mention the crank angle and a hundred other things.  

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Oh yea,  two other things

 

1) The alternator is fixed,  just a diode.  They put in a new set of NTN bearings since they already had it apart. 

2) The "High output" BNR alternator at 95A is really 65A, We bench tested it using a digital meter with the equivalent of at least 7500 RPM.

 

 

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6 hours ago, Dudeland said:

So the 123 is setting the timing.  It triggers the MSD,  then the MSD sends a signal to the sniper.  My voltage was dropping well below the limit for the MSD,  I don't fully understand why, but when the voltage to the MSD drops they get super wonky. 

Ok great, in that case, once you have the alternator voltage stuff sorted out, check things with a timing light to see where you actually are at idle and then compare those results to what you see in the datalogs.

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What I have to figure out today is why the sniper software shows all the timing controls if it isn't doing the timing. You would think that they would grey it out. 

 

 

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Ok it still isn't charging,  Now to take the battery out and get that tested. 

 

F...K I wish I was at my other house in Toronto, my tester would have nailed it down for me. 

 F....K.  5:30 am, can't sleep might as well start wrenching. 

 

 

 

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Ok now I have 14.4 volts.  I took it for a nice drive on the highway.  I will have to double check my timing.  It is off and I need to set the static timing correctly so it will read correctly on the sniper. 

 

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Well I think the AFR response looks smoother than the first datalog, so must be making some progress!  Your target AFR band seems pretty narrow though, never going leaner than 12.3, and you really want to be leaner on overrun and part throttle cruising, more like 14-15 in those areas.  But aside from timing, things look pretty good under high MAP acceleration.  AFR still seems a bit noisy in transient areas (throttle opening or closing quickly); do you know if the the Sniper is supposed to be able to 'learn' those acceleration enrichment portions also or does that need to be more manually configured somewhere?

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Here is the config file that I have.   Thanks, AustriaVespaGuy for the table I will look at it soon. 

 

Here is the latest config file.  I noticed one possibly big mistake.  The system allows you to put in actual vs expected fuel pressure,  as well as changing the output in LBS of the injectors.  

 

I mixed the two, so the injectors were showing the rated PSI at 64 instead of 60  and the actual PSI at 60 instead of 64.  

 

Also, set the startup RPM VS coolant temp to 1500, took out some startup enrichment, and generally raised the target AFR from 12.3 to 13.5 and spread it up the rpm and map range equally.

 

 

 

BMW2002 v2w.sniper

 

 

Edited by Dudeland
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Sorry, it has been quiet.  I have been experimenting with different settings.  So here is what I have found out.   

 

1) You really really really need the cable that plugs into your laptop.   Once you update the firmware you can connect the laptop in and see where in the fuel map and desired AFR in real time and you can make changes and get instant results  

 

2) See #1 

 

3) I had a problem with the idle dropping out, and couldn't figure out why.   When you see where the car is idling, and are able to make changes in real time you can really dial in on any problem

 

4) I updated my advance curve and it runs stronger, less dependent on KPA and more on RPM. 

 

I will be playing around with it over the next week, but I really feel like I directly making changes with the laptop is much easier and more efficient.  I will post what I think is a good safe base tune shortly.  I just want to makes sure that the idle hunting issue is now under control.   What I found is that where the AFR was when decelerating with the pedal closed was way-way too rich, like target  AFR of 11.4.  You can't really tell unless you see it in real time using the laptop. 

Edited by Dudeland
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I am taking a hiatus this weekend to change the oil pump.  At idle the oil light wants to stay on, so this is the third time I have had the oil pan off.  The other two times was to make sure it didn't leak.  At least I have the process down. 

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