Microsquirt

[sunnysr]

Im building a turbo m20 2.5 motor in my e30 but being a bit skint at the time of buying I bought a microsquirt instead of a standard megasquirt ..its basically the same thing the dealer told me ..it runs the same systems as ms3x and it will do everything I need.
This seems to be the case but the wires are all different to ms (less of them different pin numbers etc) .....this linked with my crap electrical knowledge isnt going well for me, I need some help.
the main issue is most the write ups etc are for proper megasquirt.

bit of spec on my car ..its a pre facelift car but ive got a face lift engine in now. im using a holset, turbo , 440 injectors, ive got a GM map sensor, GM open element air sensor, e36 tps, using the e30 coolant temp sensor, ive got the innovate MTX wideband sensor.

Now where im stuck is coil side of things! how do i control the spark I know it will need to retard the ignition so im thinking the current single coil and distributor wont be much good for that and I will have to go wasted spark ? is this right or can i make the standard set up work

I really need someone who has fitted microsquirt to see what wires they went for I have the big manual and ive read it through a good few times but it talks about mx5`s, ford ztec stuff and loads of American parts .(is there any uk cars i could take the coil set up off that im likely to find in a scrappy..gm v6 isnt)

Also the (this could be a stupid question) icv do I need it ? I have read that without it the idle with be lumpy but to fit it i need some kind of modified board thing ..the car is for drag racing it literally starts runs for 15 min then is switched off for a hour then same again between weeks of sitting on the drive a lumpy tickover really wouldn't bother me just to get it going and racing again

This might be quite hard to answer because I dont really know what im stuck on myself, I want to get the car to a point where i can start it and have it ticking over just to check the engine out ( bought from a scrap yard) and check there is no daft water leaks etc before i take it for mapping.

Cheers for any help Ive searched through other peoples thread and on the internet but microsquirt doesnt seem to be used much and oftern you get people doing builds but never get any feedback if the bloody thing worked or was reliable

[chu346]

Standard spark system is OK to get you started.

Icv isn't required

Read this:
http://www.e30zone.net/e30zonewiki/inde ... g_Your_M20

Gut a motronic ecu and use the pin outs table from the link above. You should be able to get a table for the microsquirt pin outs on the microsquirt website.

HTH

[sunnysr]

Ive had a read of that page I used some of it but with mine being an early car the pin outs were all different. I got that all figured out thought I think it was mainly the spark side not sure how to control it from the microsquirt.

did you run one with no ICV ? how did it run would be nice to cut that out the system with confidence

[chu346]

IIRC one side of the coil goes to ground and the other goes to the the microsquirt. It should say in the manual.

The icv helps to start the car when cold by adding extra air. You can do that yourself by pressing on the pedal for the first 45 seconds or so. On a non daily driver I think you can do without it.

[sunnysr]

That simple !.. I think ive over complicated things in my head to be fair, reading too many conflicting things on the internet. I did the rest of the loom in a day and it was the end of the day i was looking at the coil and thinking about timing by that time my brain was melting..since then ive read more conflicting stuff and references to unobtainable parts by American and Australian chaps.
im a pipe bends this wire bending is really not my skill set ..im learning though . I need a base map to get it ticking over but its going to a pro for mapping.

thats reassuring about the icv Thanks

[gromgsxr]

how are you going to drive the coil as the microsquirt has no igbt, you will need a logic level coil or an external ignition amplifier. if you do want to use the icv you need a 35-40 ohm resistor 50W between ground and one coil and the microsquirt fidle out put to the other.

[sunnysr]

Ok thats probably where i was getting confused I didnt understand whats driving the coil ..is there another coil i can just swap mine for and keep the rest of the system or is this where is becomes easier just to take a full wasted spark set up of something v6.
probably look a bit daft here and like i shouldnt be doing it but as most people im on limited funds and would really like to do it myself so I understand the system so when something busts i can fix it myself, ive done everything else on the car from the welding/ swapping engines and stuff I would like it to be all my work

[gromgsxr]

if you want cheep use coil off a mk 3 golf it has an inbuilt igniter so the logic level signal off a microsquirt can fire it directly, im not sure if you may need to devise a lead from the coil to dizzy cap or if the stock one will fit though.

or

get a bosch 0 227 100 124 single channel ignition amp to go between the stock coil and the microsquirt

http://i.ebayimg.com/00/s/MTA2N1gxNjAw/ ... WW/$_1.JPG

[sunnysr]

thanks for the reply, still struggling to get my head around it all tbh not sure I fully understand but im going to get a mk3 golf coil and wire that into the microsquirt and connect that to my current distributor set up.
I really want wasted spark but not sure what works with the microsquirt I read the ford system does but they have a 60-1 tooth wheel so not sure if I would have to swap to that or if that can be changed in settings. also when i looked at golf coils i forgot about the vr6 motor maybe alble to use one of them coils
finally got it all plugged into the laptop the other day and the tps was reading 40% no matter where the throttle was..decided to just get all the wires in place and take it to the mapping chap to sort it out...wish i had just bought the megasquirt.

Im wirting everything down and making a list of all the parts used etc so when im done and it all works I will post it up incase anyone else falls for buying the microsquirt.

[steve_k]

sunny, there seems to be quite a few guides online for wasted spark with micro squirt.

so far found these.

http://www.microsquirt.info/uswiring.htm

http://www.useasydocs.com/quickstart.htm

http://www.useasydocs.com/details/coils.htm

they're just microsquirt in general, might be some help might not.

[sunnysr]

Thanks for the links, i printed one of them out last night i need to read it off the computer ..anyway It has been a big mental block on my part the info is there but i have been getting stuck with 4 pot stuff v8 things and a general lack of knowledge.

so today i went and bought a golf coil as the chap above sugested ive gone through the full loom again checked all my wires plugged the laptop in reset the tps ( i had missed a wire on that so it was always at 40%) (the dizzy plug lead fits btw ) cranked the motor and i have fuel and spark , im over the moon tbh so waiting for some electrical connectors and stuff to trun up to tidy the lot up then its off to the mapping man
Thanks for the help and im going to look into that wasted spark more once i get it running because thats gotta be a better way to go.

[gromgsxr]

i guess you will be running the msextra firmware on your microsquirt so i suggest you read the msextra manual

http://www.msextra.com/doc/pdf/html/Mic ... e-3.4.html

if you wanted wasted spark a coil pack off a vr6 has an inbuilt igniter so would work great spark c would require a 1k pull up resistor between wled and the tps 5v