Little help with M84 spec /options please

[tricky]

Hi all,

First post on the forum so be gentle with me I'm fairly new to aftermarket engine manegment but I do have a good understanding of fuel injection and the operating principles.

I'm provisionaly looking at using an M84 as it seems to have everything I would ever need for my 4 cylinder turbo application. What I need some help to understand before I buy and indeed what to buy is the following ;

A> Looking at the wiring diagram the M84 has a single dedicated EGT input on pin B20, to use this input with an EGT sensor is a seperate thermocouple amplifier box needed or can the sensor be wired directly to the ECU ?

B> I'd like to run four pen coils (COP) in a CDI system obviously one per cylinder, my question is can these be wired directly to the 4 ignition outputs on the ECU or do I need another CDI / ignition amp box ?

C> Can the ECU be configured to display A/F ratio instead of Lambda ?

Thank you in advance,

Richard

[JamieA]

The EGT input allows for a Thermocouple input, but it has to come in with a thermocouple amplifier. The ECU cannot read a thermocouple directly.

As for your ignition question.
You should verify whether you really need CDI. I am running a 4 cyl turbo at up to 30 psi with bosch inductive coilsand a bosch module with no problems.

You should only run CDI if you engine needs it.

Anyhow, here are your options.

1) run inductive. you need a module channel for each coil, as the ECU cannot drive a coil directly, unless the coil has the module built in, some new coils do. Find you coil, and look for this.

2) run CDI. You will need a CDI module, we sell a 4 channel CDI module, this will be able to run 4 individual coils. Again, the ECU cannot run the coils directly.

Hope that helps.

Jamie

[tricky]

Thanks Jamie, that does help clear up a few points.

So I guess I need to decide wether I really need CDI or if two inductive (wasted setup) coils will do the job, please tell me what's your opinion from the details.

9.5:1 C/R
8000 RPM
Fiat / Lancia 4 cly 16v turbo
98 ron pump fuel
Boost level un known, but to make the 500 bhp maximium target I'd take a guess about 22-25 psi.

Any comment on point 'C' ?

Thanks so far, Richard

[Scott@FP]

Keep in mind on most good strong inductive ignition setups when in waste spark you will run out of adequate charge+recovery time (~6-8mS) somewhere above 8000 RPM, so if you plan to rev higher than 7K-8K or spend a lot of time at high RPM think strongly about going 4 channel right off the bat.

If you insist on COP the Bosch P100-T is highly recommended and has the high current IGBT transistor built in, direct hookup to ECU ign outputs.

[tricky]

Well Scott, I don't plan on spining it much faster than 8k nor holding that engine speed continualy but if that is on a good system then I suppose it can only get worse from that point, so it would make sense in that case to use a 4 channel / 4 coil setup.

I do like the COP idea, The bosch coil you mentioned I just looked up it's data sheet but I will have to measure up the plug holes because I have a feeling it will be too short to reach but thanks for the ideas.

[Holmz]

...
If you insist on COP the Bosch P100-T is highly recommended and has the high current IGBT transistor built in, direct hookup to ECU ign outputs.

I found a gem there in the Bosch catalogue - do you have any place that you recommend to get the coils that are more motorsports oriented?

[tricky]

JamieA, going back to part of my original question - I found this thermocouple (R1000) in the Motec catalouge http://www.motec.com.au/filedownload.php/?docid=3271 .

The description says a sperate amplifyer is not required and it can be connected to any aux temp input, can you confirm or deny that for me please ?

Rich

[John Reed]

JamieA, going back to part of my original question - I found this thermocouple (R1000) in the Motec catalouge http://www.motec.com.au/filedownload.php/?docid=3271 .

The description says a sperate amplifyer is not required and it can be connected to any aux temp input, can you confirm or deny that for me please ?

Rich

You can use that sensor directly, without an amplifier.

[tricky]

Cheers John

I'm starting to get a nice list of stuff I need to order now, it's just the coils.

So, apart from physical dimensions and if the coil has a built in IGBT amp or not, what should I look for in a pen coil, electricly ? ie; The bosch p100-t posted earlier has a spark energy of 100 mj is that good for an inductive coil ?

[Chris Wilson]

The P100-t is VERY powerful, you would not want a belt off one They seem capable of firing big plug gaps under loads of cylinder pressure. If you don't need that much oomph I use Toyota coils with built in amps, I discussed them in this thread, and there are photos and part numbers. At that time I didn't realise they had built in amps. They seem a cheap, popular and effective option if you don't need massive spark energy. HTH.

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