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125cc twin

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I've got this thing starting  OK now but I can't get my head around a few things.

There seems to be quite a delay with data being displayed on the laptop at times. "Setup Logging" can be slow and swapping between PC and ECU logging can be slow as well. It's probably my old laptop. Configuring gauges is slow to bring up parameters.

The engine easily spins at 800rpm just turning over at start. From what I understand this means the starting enrichment jumps straight to "post start enrichment" then to "warm up enrichment". Making adjustments in these tables hasn't been having the effect I expect. I know this engine when using another system liked 3ms injector pw cold at start. I've cranked in bigger %s but without the increases I expected in pw. It'll start but is very sensitive to throttle while cold. It will happily idle at 2500rpm typically if that could have an effect

Just starting out I'm not sure of the best basic setup. Currently using Traditional method which I'm happy with and the Equation Load source is MAP which I'm really unsure about and MAP vs RPM for the main fuel map. This seems to be easily tuned on my rolling road at fixed load points. However on the inertia dyno where nothing is steady I see problems. With a smaller throttle(25%) the AFR can go lean through load cells where if throttle is at 50-75% through the same cells the AFR is fine. This engine barely pulls any vacuum at anything under 5-6000rpm. The attached log files are from a run in the garage warming it up and looking for an oil leak. There also seems to be a regular cycle to the MAP reading which has a period of about .14s which doesn't seem to coincide with anything that could cause interference. In any case the ignition which would be the usual suspect runs along one frame rail and everything else is along the other. 12V is supplied by a car battery without a battery charger connected so a good stable supply.

What I wonder about is changing the Equation Load source to BAP/MAP. I see a problem though where at a particular throttle setting the turbo could have spooled up but MAP may not have exceeded BAP so certain throttle settings may have different airflow rates dependent on the turbo, or have i missed something. The help files are good but I just can't see how that will work.

Excuse the fuel map, we were playing and it's pretty lumpy. We parked it before we got anywhere with it due to the oil leak.

Suggestions about where to look greatly appreciated.

18_4_2 FZR125 at home logging on.pclr

2018_4_2 ECU log.llg

2018_4_2 PC log.llg

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Thanks, I've been leaning to MAP over BAP. The other thing I have a concern about is the vacuum lines to the MAP sensor. Having individual throttle bodies I combine lines from each port and then have a longer hose to the sensor. I was thinking about either a small canister or a longer/fatter hose to provide smoothing of the pulse. It'll be a balance smoothing and lag.

I'm interested in a small class of bike racing. The 4-stroke limit used to be 125cc but there were no decent engines around when I started this. I scored an FZR250 4 cylinder and using a mates bandsaw and my own little lathe cut cylinders 1&2 off, cut the crank and cams and eventually got it running with carbs and a GSXR ignition. The sound with open pipes at full noise on the dyno gave me shivers. I also had a supercharger and turbo. The turbo was chosen simply because I could fit it with the gear I had in the garage. I also found that an Ecotrons EFI for a Kawasaki GPz250 plugged straight in. Disappointingly, despite me asking and getting assurances, this system was limited to about 15,000rpm and even then I think it wasn't handling it well. So it's a 125cc twin cylinder, 4 valves per cylinder, DOHC, watercooled, turbocharged, full engine management engine. It ran to 19,000rpm on the dyno with the carbs. With the Ecotrons system it was making boost from about 10,000rpm so quite useful range if it would rev out.

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Sorry Im short on time tonight so only had a very breif look at your map.  Most of your set up is fine but you need to change your fuel table axis to TP since you have unstable vacuum.  You may need to enable a 4D table later depending on how restrictive the turbine is but start tuning without it and only add it if needed.

Your AFR target table looks a bit lean for a boosted engine so fix that up as it is used as part of the fuel calculation.

aBUZDGo.png

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Now set to MAP/BAP x-over, main fuel table axis is TP, 4D table activated with MGP on the axis. Very quick run as it's still leaking oil and it starts and runs fine up to about 5000rpm,which is as far as I went, and 20% throttle. The target lambda is just a number I put in. I'll run it on the inertia dyno and see what it actually likes and enter that value. The turbo is an IHI RH31B which is about as small as it gets but I don't see it being restrictive. I'm leaning toward tuning the main fuel table on the inertia dyno to have values which work for a dynamic engine state. If I do it on the rolling road brake the turbo will spool up fully for that load and need more fuel to match. In reality it is more likely to be less than fully spooled up, be flowing less air and need less fuel, in normal operation. I'll tune the 4D table using the rolling road at fixed loads as once you get to boost it'll just vary the MAP/MGP value. Maybe.

Thanks for checking it over

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Read my post again, for the equation I would suggest MAP rather than MAP/BAP unless you cant get it to idle satisfactorily using MAP equation.  Also leave the 4D table turned off (or zeroed) for initial tuning.  With 4D off you then fully tune the whole main fuel table at the lowest boost (wastegate spring pressure).  Once the main table is done you then increase boost and do another run - if Fuel mixture doesnt control at the target at higher boost then turn on the 4D table and use that to fix any area that has become too rich at higher boost.  Usually, if the turbo is reasonably efficient you wont need the 4D table at all.  Only if efficiency drops away at higher boost you will need the 4D table to pull a little fuel out at high rpm/boost.

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