N/A Megasquirt Thread

[NC325iC]

I know that myself and others would benefit from having a thread where we could come and ask questions about Megasquirt for N/A engines in our cars. There is plenty of background for the FI guys but not so much for those of use with atmospheric pressure. I know there are people on this board with alot of useful information to give here, and i think putting it into one place would be helpful for everyone. (see DOHC thread)

Please if you have any tips/tricks/tables/maps/advice post it here.

[NC325iC]

To start id like to ask a question.

I have been looking on DIY autotune, so far i havent contacted anyone there, at the necessary components to build the MS i want. My desired setup is to be able to tune fuel and spark, with the option open to run a wasted spark setup, fan control, and PWM idle control, all within the original motronic box. Looking at the site i believe i know what i need: a MS2 kit, motronic adapter board, fan control chip (transistor?), PWM mod kit, and in future the ignition driver.

I would like to have someone look at that and tell me if that seems correct, the only thing thats making me doubt it is looking into the DIYPNP section of that site they have a motronic 55 pin kit that uses microsquirt, this doesnt mean i have to use microsquirt to fit it in the kit does it?

[e30rapidic]

ditto!

[Gruelius]

for motronic do this

http://wiki.diyefi.co.uk/index.php?title=BMW_E30_Megasquirt_%26_Wasted_Spark_Conversion

dont buy any of the boards just wire some stuff up yourself.

if you buy a MS II 3.57 all the stuff you need is there. The only negative is that its smd (better quality but harder to fix stuff if you slip with the iron when playing with it) and that it costs more.

when you order MS II 3.57 ask the guys at diyautotune to wire the outputs you need to the extra db15 connector (3 sparks, and the optional outputs.) A list of the options is here. http://www.msextra.com/doc/ms2extra/...htm#ms2options

Anyway this should be a more generic thread. There should be a megasquirt map thread for NA users and general quesitons asked in here.

also id have the megasquirt in its own case ontop of the motronic box with wires coming out of the motronic box. As you can see from the diyefi page its a bit of a squeeze to fit it in.

[lifeiskaos]

You're on the right track. I've built over 20 plug and play MS kits for e30's, like this one:



Email me at lifeiskaos@gmail.com and I'd be happy to answer questions you've got. I've got tuned NA and turbo MSQ files too.

[nando]

there is no difference between an N/A MS and a turbo MS other than your VE and timing maps won't go above 100kpa. Well, some guys might have boost control or something set up, but that's an extra feature that doesn't affect you anyway.

if it helps here's a harness chart I created a few years ago. I update it when I find new information.

http://www.325ix.com/megasquirt/MS_to_Motronic/ms_to_motronic.html

[NC325iC]

there is no difference between an N/A MS and a turbo MS other than your VE and timing maps won't go above 100kpa.

I understand that the hardware is the same (with possible exception to MAP) but i would have expected pretty much all of the tables to be different.

[NC325iC]

for motronic do this

http://wiki.diyefi.co.uk/index.php?title=BMW_E30_Megasquirt_%26_Wasted_Spark_Conversion

dont buy any of the boards just wire some stuff up yourself.

if you buy a MS II 3.57 all the stuff you need is there. The only negative is that its smd (better quality but harder to fix stuff if you slip with the iron when playing with it) and that it costs more.

when you order MS II 3.57 ask the guys at diyautotune to wire the outputs you need to the extra db15 connector (3 sparks, and the optional outputs.) A list of the options is here. http://www.msextra.com/doc/ms2extra/...htm#ms2options

Anyway this should be a more generic thread. There should be a megasquirt map thread for NA users and general quesitons asked in here.

also id have the megasquirt in its own case ontop of the motronic box with wires coming out of the motronic box. As you can see from the diyefi page its a bit of a squeeze to fit it in.

that was very informative, those boards look like theyd make life alot easier, but there are no prices listed on that site, and i bet shipping them from england wouldnt be worth it.

[nando]

I understand that the hardware is the same (with possible exception to MAP) but i would have expected pretty much all of the tables to be different.

not really.

you don't really use other people's VE maps except maybe as a base to get started. It's going to be tuned to your engine with a wideband.

AFR works basically the same between them - stoich at cruise/low loads (maybe slightly leaner in cruise areas), ~13:1 at full load. It's just that full load on an N/A engine is 100kpa, and a boosted engine 110-200+kpa. The only difference is the load axis. Lots of boosted guys like to run a little richer (12:1 is fine), some of them like to go too far (10:1, 11:1). But that would be up in the 200kpa range where your N/A engine will never see anyway.

timing maps work basically the same. the biggest difference is the shapes of the curves (and usually a lot less timing under boost). but again, a major difference is load axis goes higher on a boosted engine. Both should be tuned on a dyno for minimum best timing (this is an ideal and doesn't always happen, lots of people street tune their maps with sucess). What really takes time is getting driveability and fuel economy tuned, here there is basically no difference between N/A and turbo.

You could load a turbo VE, AFR and ignition map (assuming it was tuned, I've seen lots of bad maps), and run it on your N/A car without knowing the difference. I started out this way. Tweaked the VE map a little to get the car "safe" (it was waaaay rich), drove it to work. My timing map went up to like 250kpa and was retarded quite a bit. My current map looks nothing like it (I modeled the curve after the stock maps)

And other than maybe adding settings for bost control, there are no other big software differences.

the only real hardware differences (aside from maybe boost control) would be if you were running more than 1 bar of boost, you'd have to upgrade the MAP sensor to something that can handle more. But again you can still use it with an N/A engine. My map sensor goes up to 4 bars.

[gearheadE30]

fwiw I'm about to install MSII on my M42, so if anyone wants specific info on that, I'll see what I can do to help. I don't have maps or anything yet, as it will probably be in the car in the next few weeks.

[nando]

for the M42 you can do a lot of cool things - true COP, sequential injection, individual mapped cylinder trims, etc. There's not enough I/O to do sequential injection on a 6 cylinder in MS2. But there is in MS3 :)

[weaksauce]

ok, there seems to be alot of stuff that is assumed with these installs.
I'd like some help to get me pointed in the right direction.
First off, i am going to be running a M30 with a 5 spd.
I also want to run a direct port nitrous kit (which i have already and piped up to the intake manifold)
I'd also like to run external coil packs (term wasted spark?)

what do i need to order to make all this work on my swapped car?

A MSII version 3?
what else?

[nando]

running an M30 is exactly like running an M20. ms2 v3.0 would be fine. you could do the diypnp kit as well and use the factory harness.

dunno about the nitrous kit, there are probably diagrams in the ms2extra manual?

[weaksauce]

running an M30 is exactly like running an M20. ms2 v3.0 would be fine. you could do the diypnp kit as well and use the factory harness.

dunno about the nitrous kit, there are probably diagrams in the ms2extra manual?

looks like the v2 daughter board is what i need.

so I'm at $315 for the ms and daughter board.
then i need a wideband and some dyno time. right?

[Cyrix2k]

subscribing to this... I'm going NA MS on my eta soon, but will be adding boost soon afterwards.