Number of injector per channel

jeeptoylander · Post by **jeeptoylander** » Sun Sep 17, 2006 11:55 pm

hi all, Lance.

Very simple question :
How many high Z (15 hom) injectors I can drive with let's say channel 1, and how many high Z (10hom) injectors on channel 2.
My intended set up is for 8 injectors gasoline on channel 1 and 8 LPG injector on channel 2 using dual table switching and B&G for MSII, not Extra.

My set up is MS V3 and MSII using latest softs.

Regards,
Eric

dridders · Post by **dridders** » Mon Sep 18, 2006 1:48 am

In this setup it might be useful to use the MS2 to control some power transistors or mosfets which drive you injectors, don't know if the MS2 can handle this current itself while not in PWM mode.
What kind of LPG injectors do you want to use? I'm going to do a similar setup, but with LoZ injectors and only 6 of them. But I'll try another way, put LPG and gasoline in parallel to bank1 and 2, so cylinder 1-3 of LPG & gasoline are on 1, 4-6 on 2. And then use a relais which cuts 12V from LPG or gasoline injectors and sends a signal to MS2 to switch the table.

jeeptoylander · Post by **jeeptoylander** » Mon Sep 18, 2006 3:16 am

dridders
I will prefer to stay stock whereas starting to modify the board with things I do not really understand, I am not an electronic wizard and do not want to f..k up. So, I would like to know if somebody try 8 Hi Z on each channel first. Unless you have a comprenhesive diagram of improving the MSV3+MSII injectors driving ability and power.

I may use Voltran brass injectors. They are les expensive than others like Keihin that cost an harm.
The way you want to merge the gasoline and LPG is the way Voltran is doing for its latest ECU. Gasoline and LPG are flowing at the same time. I do not want to mix gasoline and LPG and prefer to separate both systems on each channel in order to meter them with each VE/AFR table.
For the table switch I will use the same system as you intend, a relay switching in or off the correct channel at the same time of the LPG valve and VE.

Regards

dridders · Post by **dridders** » Mon Sep 18, 2006 3:38 am

No, you got me wrong, I will not be injecting gasoline and LPG in parallel. The ground-line (the switched one) is connected in parallel to both, but the 12V line is only connected to one of both, depending on the mode. Using that you do only have 4 injectors per channel.
If I see it right the fets on the board can supply 20A max. So you should also be fine with 8 injectors on one bank each having 10Ohm.
By the way, Voltran is also injecting a small amount of petrol during each cycle, and this is mostly only used on direct injection engines to cool down the petrol injectors.

jeeptoylander · Post by **jeeptoylander** » Mon Sep 18, 2006 1:59 pm

dridders
Sorry, yes I misunderstood and I will investigate your way...too...
20A max, that's what I had in mind too, but not so sure somebody experiment that already. . .as it may represent 16 injectors in staging/2 channels.
Other than cooling fuel injector Voltran claim also that by injecting fuel with LPG you can save the investment of another pressure reductor or big engine capacity... not so sure about that but ...
Anyhow, thanks for the reply.

Cheers,

Bye

dridders · Post by **dridders** » Mon Sep 18, 2006 2:08 pm

It's 20A per bank, as each bank has one mosfet. But it may need some more cooling, watch the heatsink.
You're right, I read something like that too, but... I think it's only interesting for engines with a high per cylinder power, which cannot be fitted with one injector of largest size. The reductor isn't that expensive, so it makes more sense to mount a second one if really necessary than to use petrol... no one likes to use petrol if he can use gas ;-)