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Megasquirt ON BMW m52 Engine

Posted: Fri Dec 23, 2011 6:28 am
by maxo-tt1
hello people :) i've just bought ms3x ecu and and wanna tune my car with myself :) (i've never done it before).

so if someone has any important experience, please share :)

except an ecu, what do i need to buy?

i have to buy this? http://www.diyautotune.com/catalog/quad ... p-481.html

i've seen wiring here http://www.msextra.com/doc/ms3/hardware.html

what's the difference between m50 and m52 wiring?

may i use this?
http://www.megasquirt.325ix.com/MS_to_M ... 3.3.1.html

any recommendation is useful for me :RTFM:

thanks

Re: Megasquirt ON BMW m52 Engine

Posted: Tue Dec 27, 2011 10:27 am
by lastermann
You don't need that ignition module, you ve COP on your car and you need to find a way to ignite your coils with MS3X spark outputs. You may also consider switching to a VW coils, they're logic level and you don't need extensive modifications. I am currently running VW coils (COP) on my M20 engine. I recommend keeping original wiring loom and using RS motorsport's cable harness instead, so you can switch to original setup at any time easily. A wideband sensor and its controller is a must, buy Innovate motorsport's LC1, and first of all make sure that you'll be able to control your Vanos, without controlling Vanos correctly your m52 engine will only go worse. In my opinion M52 engine is no good for playing, Its already perfect, If you really wanna play, buy a classic and setup MS3 on it.

Re: Megasquirt ON BMW m52 Engine

Posted: Tue Dec 27, 2011 11:34 am
by maxo-tt1
thanks for reply.

its now clear about ignition.

i've bought ecu and innovate lc1 kit allready. they'll arrive on 3'th of january :yeah!:

so i'll start as soon as possible. and will write here everything i've done.

yes, vanos is really headache. i have no idea how tu make vanos work.

so its better buy m50b25 non vanos head and rebuild yes?

can y help me finding proper "RS motorsport's cable harness"


p.s
i'm from georgia, sorry for mistakes :P

Re: Megasquirt ON BMW m52 Engine

Posted: Tue Dec 27, 2011 1:05 pm
by lastermann
http://www.diyautotune.com/catalog/1239 ... p-451.html
http://www.diyautotune.com/catalog/1239 ... -p-43.html

these are cable sets, you'll need both, don't try to build yourself, it will cost half price but with full of headache. 90% m50s have vanos, but single, yours have double vanos, (exhaust&intake) and it doubles the pain. m50 & m52 engines can also be tuned by simply reprogramming the motronic ECU, its much easier and better to do this way. MS is great for upgrading carburated and some older engines with oldest technology. Your engine has already COPs, O2 and knock sensors, Vanos etc., its a perfectly tuned engine with latest technology and I'd rather keep it original. and if you wanna modify just do it with stock ECU via connecting to OBD2 port on your car. However if your aim is to leaarn and experiment buy and e30 3.25i and play with this oldskool just as I do.

Re: Megasquirt ON BMW m52 Engine

Posted: Tue Dec 27, 2011 1:23 pm
by maxo-tt1
mmm... why not biuld it myself? its easy to get db37 conenctor and build the same wiring :roll:

yes i know about motronic, but i plan turbocharger soon, and i think megasquirt is better for high boost.


and i have another problem, cant find my stock siemens ecu (ms41.1) wiring diagram :(

searched the google but nothing. any idea where to find it?

Re: Megasquirt ON BMW m52 Engine

Posted: Tue Dec 27, 2011 1:45 pm
by lastermann
No idea about where to find it, however I want to emphasize once more, you may need your stock wiring harness if you want to revert back to stock ECU, so keep it. If you want to build your own harness you need to make soldering perfect, and require hundred meters of cable with no labelling on them, I bought harness ready and never regret it. And once more, m50 engine is not for turbocharging, its a well balanced atmospheric engine, I hope all your investments on it will pay-off.

Re: Megasquirt ON BMW m52 Engine

Posted: Tue Dec 27, 2011 2:24 pm
by James
Buy a wiring harness, it's so much easier!

Re: Megasquirt ON BMW m52 Engine

Posted: Wed Dec 28, 2011 12:37 am
by maxo-tt1
mmm, its better make new wiring?

i thought about getting X88 pin connector from stock ecu, and connect it to db37 with small cables...

like that:

Image

and if something goes wrong, it'll be very easy to return on a stock ecu.

:roll:

Re: Megasquirt ON BMW m52 Engine

Posted: Wed Dec 28, 2011 2:52 am
by James
That's a very good idea if all the wires are available there.

Re: Megasquirt ON BMW m52 Engine

Posted: Wed Dec 28, 2011 10:46 am
by hassmaschine

Re: Megasquirt ON BMW m52 Engine

Posted: Wed Dec 28, 2011 11:16 am
by maxo-tt1
hassmaschine wrote:wiring diagrams for BMW:
http://www.wedophones.com/BMWManualsLead.htm
wow. good job. thanks! :yeah!:

Re: Megasquirt ON BMW m52 Engine

Posted: Wed Dec 28, 2011 1:05 pm
by maxo-tt1
i started doing ms41.1 to ms3x wiring diagram.

can someone help me to check and complete it? (or maybe someone has it completed :roll: )

its a first half. i'll do full tomorrow.

Image


ms41.1(m52) wiring diagram:
http://imageshack.us/photo/my-images/815/ms4111.jpg
http://imageshack.us/photo/my-images/845/ms4112.jpg
http://imageshack.us/photo/my-images/860/ms4113.jpg


p.s
if i use this http://www.diyautotune.com/catalog/bosc ... p-230.html
can i use stock coils? or i don't need it?

Re: Megasquirt ON BMW m52 Engine

Posted: Wed Dec 28, 2011 1:26 pm
by hassmaschine
another reason I like doing it the way in the picture, is it makes working on MS much easier. I also don't like having the DB37 hardwired into the car - I did it that way last time, and I regret it.

Re: Megasquirt ON BMW m52 Engine

Posted: Thu Dec 29, 2011 9:53 am
by maxo-tt1
little updated version.

changed sparks and injectors like firing order

Image

dirrect img url: http://i39.tinypic.com/2ecq5ud.jpg

Re: Megasquirt ON BMW m52 Engine

Posted: Fri Dec 30, 2011 4:57 am
by maxo-tt1
ecu has been arrived today.

i wanna test it, how to connect it to computer?


its m3sx

i connected it with this cable

Image

but in which pin does 12v goes?

Re: Megasquirt ON BMW m52 Engine

Posted: Sat Dec 31, 2011 2:50 am
by howelll
Making a harness adapter from the old ecu case is how i did mine. My m52b28 is a single vanos, I used the obd2 m52 harness but i used a m50 cam sensor wired separate, the m52 uses CID cam sensor which i couldn't get to work. I used the old case to also hold the ignition drivers circuits to run the factory ignition coils. Your crank trigger should be in the neighborhood of 325 degrees but you should verify with a timing light. Is this engine in the original car or a swap to another body? just curious

Re: Megasquirt ON BMW m52 Engine

Posted: Sat Dec 31, 2011 5:03 am
by maxo-tt1
howelll wrote:Making a harness adapter from the old ecu case is how i did mine. My m52b28 is a single vanos, I used the obd2 m52 harness but i used a m50 cam sensor wired separate, the m52 uses CID cam sensor which i couldn't get to work. I used the old case to also hold the ignition drivers circuits to run the factory ignition coils. Your crank trigger should be in the neighborhood of 325 degrees but you should verify with a timing light. Is this engine in the original car or a swap to another body? just curious
yes the engine is in original car.

hm, useful info about cam sensor. thanks :RTFM:

to make my stock coil work, i gonna buy this
http://www.diyautotune.com/catalog/bosc ... p-230.html

its right?

can u share your ms41 to ms3x wiring diagram please? :roll:

Re: Megasquirt ON BMW m52 Engine

Posted: Sat Dec 31, 2011 8:40 am
by jsmcortina
maxo-tt1 wrote:ecu has been arrived today.

i wanna test it, how to connect it to computer?
All the info you need is in the manual.

Read the MS3 manual starting at the QuickStart page. http://www.msextra.com/doc/ms3/quickstart.html

Re: Megasquirt ON BMW m52 Engine

Posted: Sat Dec 31, 2011 8:57 am
by maxo-tt1
jsmcortina wrote:
maxo-tt1 wrote:ecu has been arrived today.

i wanna test it, how to connect it to computer?
All the info you need is in the manual.

Read the MS3 manual starting at the QuickStart page. http://www.msextra.com/doc/ms3/quickstart.html
thanks, useful link.

i just wanna know in which pin 12v goes(i care about that thing. dont want to connect it in wrong pin and damage something). is it 28pin (brown) on v3 mainboard?

thanks

Re: Megasquirt ON BMW m52 Engine

Posted: Sat Dec 31, 2011 9:14 am
by jsmcortina
Yes. Connect FUSED 12V to pin 28 and ground to any of the ground pins.

James