LH2.4 to MS2 [MAF based]

[DailyDriverMods]

So... I decided that switching to a MS2 in my daily driver is a great idea that shouldn't be too difficult and couldn't possibly go wrong.

The setup is going to be a B230F which running on both petrol and LPG. (dual fuel, altough not at the same time) Table switching will be very nice in this case so i can use a different AFR and ignition table for LPG which should give more performance and better fuel economy than just running it with a petrol tune. (especially with a turbo that will added later on)

The idea is to put the MS2 in a LH2.4 housing so it is relatively plug&play and i can switch back to the LH system if i want to. Once the MS2 is dialed in and i'm satisfied with the tune i can start to install it more permanently and add things like a TPS and IAT and continue the +T swap.

At first i'm going to use all the stock sensors, including the stock MAF sensor. Only a MAP sensor and a wideband will be added. The fueling will be MAF based, the ignition and acceleration enrichment will be MAP based. So it's going to be a MAF/MAP mix tune which will hopefully give a nice adaptive tune that will be great for daily driving. No VE table will be neccessary.


https://tweakers.net/fotoalbum/image...KCSNsTSAZx.jpg (bigger picture)

The ECU is an EFIgnition46 unit which is a Dutch high quality MS2 clone. I created a little daughterboard to help the ECU with the system relais switching, table switching (based on the LPG solenoids opening/closing) and the burn-off procedure for the MAF sensor. There is also an additional connector for the extra sensors and such later on. (just a standard atx 24pin)

I'm still waiting for the 14point7 wideband and the ECU connector. Once i've got them i can wire it all up and try it out. In the meanwhile i'll be trying to make a base tune and figure out all the options that MS2 has.

[TurboDutch]

Why not make everything map based and ditch the damn maf... I have the feeling that you are making your life too difficult ... Anyway more difficult than neccesary, if you allow me :p

[DailyDriverMods]

Well, i've looked into it and actually prefer the MAF tuning stuff since you directly measure the amount of air that enters the engine. It can always be ditched if it doesn't work out, i just don't really get it why people generally are so eager to ditch the MAF sensor...

[linuxman51]

its not a 0-5v device, so that's going to be the first problem you'll run in to

[Cwazywazy]

I found using the MAF with my MS2 was easy once I got a decent curve mapped and it meant I didn't need a TPS since acceleration enrichment wasn't really something I needed to worry about. I ditched the MAF simply because they kept breaking.

[DailyDriverMods]

Originally Posted by linuxman51

its not a 0-5v device, so that's going to be the first problem you'll run in to

I was planning to use a buffer opamp and a resistor voltage divider to keep it nice between 0-5v but i'm afraid that it may add too much noise to the signal. Since the car is NA, it probably won't ever operate above 5v. (or at least expect usable data in that range) So adding that circuit will only give extra trouble. Once the turbo will be added, i will switch over to a Bosch HFM5 maf that is nicely 0-5v and doesn't need the burn-off procedure. The are used in the Volvo 850 and such so they are easy to get.

@Cwazywazy
That sounds promising, except for the breaking part. What MAF sensor did you use?

[linuxman51]

then make the switch up front. don't overcomplicate this. (although, if you're using a maf why bother with the map)

[Cwazywazy]

I really don't think you'll hit 5v with an NA. Maybe with a killer 16v setup. Most I ever saw was about 4.9 or 4.95v with my 007 maf at around 22psi. And if you plan on switching MAFs, it probably makes sense to do it now if you can save the connector, wouldn't be too much work to swap back to the stock one if you want to switch to the stock ECUs.

[linuxman51]

the 016 and 012 mafs both maxed out on my stock 940 turbo at 15-16 psi back when I played with it. at idle they sit around 2.5 or 3. if the plan is turbo and a different maf, go ahead and get the different maf now

[DailyDriverMods]

Swapping the MAF straight ahead indeed makes more sense.. then i only would have to make the MAF map once. But i just have the tendency to overcomplicate things. The additional MAP sensor will still come in handy for the AFR table, ignition table and boost control through the MS2. This way, the calculations aren't depending on the volumetric efficiency of the engine and i don't have to guess when the engine is on or off boost based on a load number. (when the turbo swap is finished)

The HFM5 MAF sensor looks nice:
https://members.rennlist.com/jandrea...%20Sensors.pdf
Volvo used the Bosch 0 280 218 108 (HFM5-6.4) with their ~250hp 5 cylinder turbo engines.

[Dirty Rick]

I don't think that is a licensed MS2 derivative, if so it is not legal to use B&G or MSextra firmware on it.

http://www.msextra.com/doc/pdf/licenses.pdf

[TurboDutch]

Yes I agree there is nothing wrong with either maf or map... but the stuff comes with onboard map so why not use that.

I really like maf tunings too, and if you are planning to use a 850maf you could easily convert it into 3.25 in turbo application we are doing this in M44 worlds :P

But yeah... about over complicating things... :P and even with maf we are using VE maps... so... yeah :P

The ecu you are planning to use (efi46) is indeed not licensed it is an unlicensed copy... but they seem to work nice...

I'm going microsquirt :D also with LPG :D

[DailyDriverMods]

Yup, i saw that it officially isn't allowed to use the MS firmware on it. But they won't license anything other than their own hardware (which isn't better than some of these "clones"), and they don't offer a "pay $50 and YMMV" option to support their work either. So i can't really do anything about that. I really appreciate their work and brilliant firmware, but we already had this ECU laying around for a couple of years, otherwise i would have bought a microsquirt kit or something. But i'm not going to replace perfectly working hardware.

The brand new 16T also arrived today, they are so shiney when they are new.

[VB242]

I've thought about hooking up the Ford Lightning MAF, I believe MS2 already has the curve setup. I would think it would cover as much airflow that my B23T could generate

[linuxman51]

at the end of the day, load is load.. if you have load coming in from the maf, it doesn't matter if it's "in boost" or not, that'll just be a load point on the map.

[TurboDutch]

Originally Posted by linuxman51

at the end of the day, load is load.. if you have load coming in from the maf, it doesn't matter if it's "in boost" or not, that'll just be a load point on the map.

Can't argue with that...

[bobxyz]

To drop the LH2.4 MAF voltage, you can just use a 2 resistor divider. I'd try a total resistance around 50K to keep the load on the MAF low.

Your bigger problem is that LH2.4 uses a hot-wire MAF that needs an occasional burn-off cycle. I don't know how you'll do this with megasquirt. It would be easier to find a more modern thin-film MAF that doesn't need a burn-off cycle, preferably one with a good MS calibration chart already available. (I think ipdown still has partial datasheets for the 012 and 016 AMMs.) Or just use MAP like everyone else suggests.

[DailyDriverMods]

Originally Posted by bobxyz

To drop the LH2.4 MAF voltage, you can just use a 2 resistor divider. I'd try a total resistance around 50K to keep the load on the MAF low.

Your bigger problem is that LH2.4 uses a hot-wire MAF that needs an occasional burn-off cycle. I don't know how you'll do this with megasquirt. It would be easier to find a more modern thin-film MAF that doesn't need a burn-off cycle, preferably one with a good MS calibration chart already available. (I think ipdown still has partial datasheets for the 012 and 016 AMMs.) Or just use MAP like everyone else suggests.

The MAF burnoff cycle would be done as following:

The MS2 got programmable outputs. One output would go high when:
runtime -> 20 minutes

This signal will be fed into a ATTINY microcontroller. Once it detects that the signal is high, it will trigger the following routine:
- Once the signal goes low again (that's when the engine is turned off), the system relay will be kept turned on and the MAF buroff signal will be sent for a period of time. (somewhere from 5 to 20 seconds i saw in the documentation)
- Once this time threshold is met, the burnoff signal will be low again and the system relais will be turned off. Easy as that. (LH isn't really that complex)

But since i'm probably going to swap the MAF right away, i won't be using this.