Motec M4 + Multiple Coils ?

[gnki'vlct]

hey!!! (ive made this topic everywhere.. but i shouldve done it here coz of the head im using)

bloody hell had to remake another account because i forgot my username, but hey I own a vl calais turbo and im just about to put a rb26/30 into my car..

the motor is out at the moment (i bought it off someone else who also had a vl) and just before i put it in my car i need to know what to do....

previously the engine was running off a microtech ltx12s (or lt12s if its the same shit whatever lol) and the car is still in its run in tune, at 10psi.

so having said this i could get the ecu off the guy aswell, and plug his into my car and away i'd be.

he also has a decent coil setup. but id probably give him my motec m4 and i'd pay less for the engine or watever ("cash adjustment")

now my dilemma.

im really confused and i have nfi what to do with my Motec m4 (which i still own)... it sez on their webpages etc that it can run upto 4 ignition drivers? then people said what u do is batch them or whatever..... but it wont be as good as the lt12s coil setup or whatever...blah blah

well this is what ive been told so far -

you can run a Motec 'ignition expander' (runs up to 8 coils) and use batch or semi seq fire for inj, no probs

Or if you want / like CDI ignitions, use the motec CDI-8 module, easy as. both of these interface directly with the M4 ecu.

and then..

"As trev and shazza said, if you dont wanna run the expander, just run wasted spark instead of sequential, with 3 Bosch coil packs and you'll have an ignition output spare.

I dont know who told you that batching them will make idle bad, but its totally not true if its tuned correctly. It just means that the coil fires during the power cycle of two cylinders, rather than just one"

i am soooo confused and dont know what to do ay.

all i know is i gotta buy atleast an "ignition expander" for 330bux or i could pay nearly 2grand for some CDI bs... which seems shithouse coz thats too much.

what do yas reckon is my best option.. go for the ecu which is good enough and is aleady tuned etc (microtech) or go the motec way???????

big thx.

ps - dont tell me to speak to my tuner lol, i will but its a public holiday on monday, so they wont be open and i NEED TO KNOW WHAT TO DO ASAP!!!!!

Edited March 3, 2007 by gnki'vlct

[Adriano]

I would get a set of EL falcon ignition coils and run wastespark, there is no problem with wastespark, as heaps of factory and high performance cars run it. Set your dwell time to 4ms. If down the track you find that you need more spark grunt, you can easily fit a 4 channel cdi unit($600)and the coil block which is quite neat is about $120 brand new from ford. The coils even have the cylinder numbers already marked on it to make it easy to hook up the coils to the spark plugs.

[rob82]

Just to clear a few things up wasted spark fires 1 cylinder on the compression stroke the other on the exhuast stroke.

4ms of dwell at 13v is a fair amount I would probably run around 2.5ms - so you dont burn coils out.

Wasted spark is not what I would be worried about. Its the batch firing of the injectors that I would be most concerned about if it is to be a street car. However the microtech in sequential mode is probly a little bit better than the motec in batch fire and its allready setup and tuned so I would be leaning on going down that path.

[T04GTR]

yeah. eithere get 3 double ended coils or get the igniotion expander.

[Adriano]

4ms wont burn out mitsubichi or ford coils, weve tested them extensively, and thats the point where they produce maximum spark energy, any more and there's no gain. Nissan coils will burn out in no time though.

[gnki'vlct]

so how much will i need on the side to spend???

get 3 coils? theyre 50each.... then the motec ignition expander? would this be all i need to spend? (the car will probably be making around 400-450rwhp and thats through an auto transmission)

coz im pretty tight atm... lol and this pisses me off all these things about "batch firing" and "sequential"...

*sigh* wish i wouldve just bought an m600 from the start

Edited March 4, 2007 by gnki'vlct

[Adriano]

falcon coils, no ignition expander. you will need igniters or cdi to switch the coils though. Have a look on the motec wewbsite, its fairly self explanitary