Megasquirt is on the way.

[bjl4776]

JonK took the trip up and bought my M50 off of me today. I have been plannin on put megasquirt on my 95 325is for sometime, but have lacked the motivation to spend the money on it. We'll I finally ordered it today and the parts should be here within the next week. Im using MS for both fuel and ignition, and Im doing it on a vanos motor that is relatively stock for now. So if anybody wants to try this on a M50 i will have the base fuel and ignition maps for the stock motor. Hopefully I can figure this thing out without too many headaches, but we will see. And all this just a few weeks away from picking up my 95 Dakar yellow M3, so much automobile fun so quick. My wallet is just burnin away.

[kyleN20]

about homew much are the e36 m3s running for now?

[bjl4776]

Iv seen them for 9-19k. If you want the the OBD-II low mileage, your looking at spending over 15k. I wanted the OBD-I, so 95 was my only option, and mileage wasnt as much of a concern as condition as I don't mind the maintence. The one im pickin up is 9.5k, but has a mint body, paint, and all service records. I havent seen many 95s in this kind of condition, but the guy just needs to get rid of it, but he isnt advertising it. I heard about it because he is a friend of a friend.

[bahnstormer]

boo on odb2

[kyleN20]

thats sweet, id like to drive one of those

[Booster]

Very cool BJ.,
I plan on using MS ,but only to run dual added injectors via a boost signal/MAP sensor. From all I've read, most installs have gone great and they love them.I know of at least 7 built cars running them now for over a year and no regrets yet !
keep us posted..........Vinny:)

[Jon K]

Very cool BJ.,
I plan on using MS ,but only to run dual added injectors via a boost signal/MAP sensor. From all I've read, most installs have gone great and they love them.I know of at least 7 built cars running them now for over a year and no regrets yet !
keep us posted..........Vinny:)

Brandyn, nice! I knew you mentioned buying it but I didn't think you would be doing it the day after I bought your motor :) Nice man, the most fun part is building it honestly. Still putting my car back together. You said you will have the base maps for fuel for the M50? I'd like to see those. Timing as well.

Booster - you want to run additional injectors supplemental to the the stock DME? That's a bad idea - MS is not really designed to do that - it can, but the whole purpose of the unit is to standalone control the fuel and or timing. You will have a hell of a time dialing in the megasquirt while the stock DME is adapting the stock injectors...

[Booster]

Brandyn, nice! I knew you mentioned buying it but I didn't think you would be doing it the day after I bought your motor :) Nice man, the most fun part is building it honestly. Still putting my car back together. You said you will have the base maps for fuel for the M50? I'd like to see those. Timing as well.

Booster - you want to run additional injectors supplemental to the the stock DME? That's a bad idea - MS is not really designed to do that - it can, but the whole purpose of the unit is to standalone control the fuel and or timing. You will have a hell of a time dialing in the megasquirt while the stock DME is adapting the stock injectors...

Hmmm. I see what you mean. I was wanting to avoid commiting the car to a standalone for now and just use the MS as a seperate signal reader for when the boost is signaled.
Are you saying that the stock ECU will sense boost or perhaps be unable to operate under boost ?
I was hoping it wouldn't recognise any boost and the MS could control additional fuel needs to the supplimental injectors alone ? AM I wrong here ?
Maybe I should just follow your steps carefully while you do the MS install and do the same. Afterall........its not as if the car is new for crying out loud. How can it devalue its self if it runs strong and is properlly tuned ? It won't really..IMHO,anyway.
I won't run boost above 10 psi for my needs .....so talk to me about this.Please.....;)
..........Vinny

[pyro]

quick q about ms... Can you ever plug in your stock ecu to smog your car?

[Jon K]

Hmmm. I see what you mean. I was wanting to avoid commiting the car to a standalone for now and just use the MS as a seperate signal reader for when the boost is signaled.
Are you saying that the stock ECU will sense boost or perhaps be unable to operate under boost ?
I was hoping it wouldn't recognise any boost and the MS could control additional fuel needs to the supplimental injectors alone ? AM I wrong here ?
Maybe I should just follow your steps carefully while you do the MS install and do the same. Afterall........its not as if the car is new for crying out loud. How can it devalue its self if it runs strong and is properlly tuned ? It won't really..IMHO,anyway.
I won't run boost above 10 psi for my needs .....so talk to me about this.Please.....;)
..........Vinny


The stock ecu uses a MAF, which understands air flow but not air pressure. The MS ecu uses a MAP, which understands air pressure... The stock ecu will operate with boost etc, many people have a chip burned for their setup. However, i wasn't talking about hte stock ECU not working under boost, but what happens is, your car monitors the O2 sensor and add/subtracts fuel to make sure the output is stoichiometric, or close. So if you have MS adding fuel to the engine and stock ECU doing fuel as well, the stock ecu will see a rich condition and subtract fuel, which is going to really throw off the MS unit since it is adding fuel and the stock is subtracting and the AFR is going up and down at similar times.

Also - the stock ECU adapts... meaning, at full throttle it runs from a pre-programmed fuel map but sometimes in part throttle it runs off of AFR-target, sort of. So, gradually, over miles, it will trim or add fuel by instinct and with MS doing its thing, it will get real confused.

Also - something you probably have not though of yet - you can't just hook MS into stock injectors. You would need to add injectors... but since the motors are direct port injection... you'd either need to add 6 additional injectors, one to each port (good luck) or do throttle body injection which is really a step backwards in technology.

Finally- just because you use MS does not mean you're running a "standalone". You can run MS for JUST timing, JUST fuel, or time AND fuel. So, you can literally got the wires from the stock ECU to the injectors, and splice them into the megasquirt. Stock ecu won't even know they're missing, it will send signals over dead wires. Meanwhile, MS is triggering your injectors and you are ready to go. If you're running 10psi I hope you have 30# or larger injectors.

[Jon K]

quick q about ms... Can you ever plug in your stock ecu to smog your car?


No, the MS is not plug and play with the stock ecu, meaning you cannot just throw the stock ecu back in. You can, however, lean the car out if you want to get it smog tested. I am lucky and know someone who can take care of my emissions for me.

[bjl4776]

I ran 10psi with the stock ECU on a stock M50. I used 30lb injectors, rising rate FPR, and SMT-6 piggyback, cause the MAF didnt like reading boost at all, as soon as it detected boost it would through a CEL, and start running rich as hell, the SMT allowed me to alter the O2 and MAF signal back to the ECU and trick it into thinking it was doing something else. I couldnt run the fuel 10psi unless I was running a half tank of race gas, and half tank of 93. I didnt run 10 that often, I mainly used 6-8psi, unless goin to the track, or after getting a good enough paycheck to spend 5/gal on gas

[bjl4776]

I wasn't gonna buy it, but since I was working on it, it got me into the mood, and since I had some extra cash I figured now was as good a time as ever. I don't have the base map currently, but when I get it running I will tune it to a stock M50. I am pretty sure I am going to get a 36-1 wheel machined for it and just use the Ford EDIS control module to run the ignition.

[Booster]

The stock ecu uses a MAF, which understands air flow but not air pressure. The MS ecu uses a MAP, which understands air pressure... The stock ecu will operate with boost etc, many people have a chip burned for their setup. However, i wasn't talking about hte stock ECU not working under boost, but what happens is, your car monitors the O2 sensor and add/subtracts fuel to make sure the output is stoichiometric, or close. So if you have MS adding fuel to the engine and stock ECU doing fuel as well, the stock ecu will see a rich condition and subtract fuel, which is going to really throw off the MS unit since it is adding fuel and the stock is subtracting and the AFR is going up and down at similar times.

Also - the stock ECU adapts... meaning, at full throttle it runs from a pre-programmed fuel map but sometimes in part throttle it runs off of AFR-target, sort of. So, gradually, over miles, it will trim or add fuel by instinct and with MS doing its thing, it will get real confused.

Also - something you probably have not though of yet - you can't just hook MS into stock injectors. You would need to add injectors... but since the motors are direct port injection... you'd either need to add 6 additional injectors, one to each port (good luck) or do throttle body injection which is really a step backwards in technology.

Finally- just because you use MS does not mean you're running a "standalone". You can run MS for JUST timing, JUST fuel, or time AND fuel. So, you can literally got the wires from the stock ECU to the injectors, and splice them into the megasquirt. Stock ecu won't even know they're missing, it will send signals over dead wires. Meanwhile, MS is triggering your injectors and you are ready to go. If you're running 10psi I hope you have 30# or larger injectors.

So let me see if I'm reading this right ? Your saying that the O2 sensor will read an over rich condition even though the boosted signal requires the additional fuel and SHOULD burn it ? AT least as long as the AFR is decent/acurate ?

It would make sense that my idea is far from "most efficient" compared to a full "stand alone", but I thought it would be workable. Perhaps your putting your foot down and saying "No" ?

I guess I should ask....what are you planning on continuing using , such as factory A/C etc. What functions must continue with the factory ECU ?

I would like to build this so I don't have to struggle with fuel choices if at all possible ?:(

[bjl4776]

The computer can compensate to a certain extent, but after that it goes crazy. The MAF can't read boosted air. And if you want to boost high, a piggyback won't even suffice because it can't do anything beyond the capability of the DME. When you boost a MAF setup you have to move the MAF infront of the blower, and then it gets peaked out easily under boost. The most efficient setup would be a full standalone, but you can make do with other setups.

[Booster]

I do like the idea Jon mentions about using 30lb injectors signaled by the MS and deadheading the stock wires signal.
Does the stock M50 come with any knock detection factory ? I believe I read that the MS does have means for knock retard.
But considering that the MAF placed in front of the compressor will peak out quickly, it really sounds like using the MS to control spark and fuel is the way to go.
What functions should be left to the factory ECU to control ?

[ArtemLepilov]

Stock M50 has a knock sensor, no matter when the engine came out.

-Artem

[hakwuzhere]

Stock M50 has a knock sensor, no matter when the engine came out.

-Artem

Im probobly pretty uninformed here, but I thought that the NonTU M50 didnt have knock sensors.... they started in 93..

[ArtemLepilov]

Nope, all M50s had them

[Booster]

Nope, all M50s had them

Guys.........is it possible to utilize this stock sensor in relationship with the MS ? IS it made to work within the same parameters ?

[bahnstormer]

it may be
the MS has inputs so just figure out what voltages the oem knocks put out and config

in theory at least...

[bjl4776]

the M50 non vanos did not have knock sensors, only the M50tu. You can use the stock knock sensors on MS. There are a million and one different things you can do with MS. It came in the mail today. It isnt bad at all to solder the PCB, I built the stimulator and I got the power supply on the board workin and it took me like 2-3 hours, with plenty of roomate interuptions.

[Anton CH.]

bjl4776,
Can you follow up on your MS install? I am debating on wether to have my Bosch DME tuned or just buy the MS unit.



Knocksensors are pointless in my opinion. They are not reliable for high RPM, meaning you want them off at high rpms. So kinda useless on a boosted motor when all the boost is at high RPM.

[Jon K]

bjl4776,
Can you follow up on your MS install? I am debating on wether to have my Bosch DME tuned or just buy the MS unit.



Knocksensors are pointless in my opinion. They are not reliable for high RPM, meaning you want them off at high rpms. So kinda useless on a boosted motor when all the boost is at high RPM.


Actually, currently MS does not support knock sensor reaction. All it can do is datalog knocking, which is actually VERY useful for tuning your car... but knock isn't too hard to hear. If you have doubts about whether you're knocking or not, you're already running too lean.

[bjl4776]

Yea, im going to be trying to get the board updated on the install. The building of the unit is really easy, the kit I got has everything labeled. I got the power supply working and im ready to test the serial port, and prossesor, but im at work right now and dont have my laptop. I went to a machine shop this morning and tried to figure out how to make a 36-1 tooth wheel from the 60-2 wheel. As soon as I get the wheel thing straightened out ill order the rest of the parts such as sensors, and wiring harness and such, and try to get it going. JonK said he got his current motor running with fuel only from megasquirt already, so it gives me more confidence.