MicroSquirt.com read only forum (Jan.15,2018)

Hi , ive read that we can trigger coils directly with microsquirt. I have a CB750 1975 motorbike to convert to EFI and i wanted to go EDIS. After reading some i came across the possibility of driving coils directly with the Microsquirt. What i am wondering is would this direct coils driving only need a trigger and a VR sensor? The timing advance map is controlling the direct drivers just like the map is controlling the EDIS module with the PIP/SAW ? I also want to control the injectors seperately and i dont have a cam sensor so i think the 36-1 trigger is the best option. Please correct me if im wrong!

I also read that driving the coils directly is making lots of noise so i will shield the wires accordingly.

I MSquirted a 1990 VW 2.0 16V Turbo with The full EDIS setup years ago and it worked pretty well but the motorbike build asks for the least added parts possible so if i can ditch the EDIS module i'd be happy

Thanks

Oliver

Oliver,

You can run either EDIS or 'direct drive' coils with microsquirt. Either would be wasted spark on a four cylinder engine (because microsquirt only has two ignition outputs, and the EDIS does not have a cam sync signal).

For details on how to set-up wasted spark on a 4 cylinder engine, see 3.a here: http://www.useasydocs.com/details/dualspark.htm (be sure to read the notes too)

For more information on using coils, see: http://www.useasydocs.com/details/coils.htm

Lance.

Humm , does it means i can use my Dyna S double pickup on the crank to drive MS? Its a 1975 CB750 motorcycle and has mechanical advance wich twists the magnet holder on the crankshaft to give the advance. i could weld it solid so it keeps the base timing. Im not sure this is the best way of doing it since MS wouldnt have any clue where the camshaft is but would be alot cheaper and less complicated than the trigger wheel install.

Thing is that my engine is aircooled L4 and the center cylinders are way hotter so i would like to be able to run them a bit richer than the exterior so controlling each injectors independently would be preferable and i think MS has to know where is the cam to control the sequential injection , correct me if im wrong theres so many possibilities within Megasquirt sometimes my head starts to spin.

So , do i need the 36-1 or im just complicating the install for no reason? I actually found a perfect 2" trigger wheel and an ajustable sensor but didnt ordered em yet.

Thanks for the links

Hi
Isn't your CB750 the SOHC model?
Can you not fit a cam trigger off the timing chain, I'm sure there is room.
If you did this, you would have wasted spark, 1&4, and 2&3 cylinders like stock, and wire your injector likewise, so 1&4 is INJ1, and 2&3 (aka the hotter middle cylinders) would be INJ2. Obviously, you'd use the Dual Tables set up to independently control INJ1 & INJ2.

I'd also mention there are some great single fire & wasted spark coils out there, on cars admittedly, so would be bulky, but they are a lot cheaper than some of the aftermarket stuff. Some of the GM 2 x 2 coils set ups have low voltage triggering, ideal for your MicroSquirt v3, and it's a lot less than buying a separate ignition module too.

Just a thought
Mike

PS For a compact 4 x 1 single fire set up with 5V triggering and a built in module, have a look at a VW Bora Golf Beetle coil 06A905104 or RUF484.
and for a compact 2 x 2 wasted spark set up with amplifier, GM 90443900 or Bosch 0-221-503-001

Yes it is the SOHC but seriously installing the 36-1 is gonna be real easy , the cam sensor would be alot more work so im gonna install the 36-1. I already have the Dyna coils wich are wasted spark , already installed in the bike's stock location and they give plenty of spark i think theyre 3ohms i have to check so i will use the direct drivers .

Only thing to confirm now is that i dont need the 36-1 trigger paired with the EDIS module . Trigger talks to the MS and MS drives the coils and his advance , thats it? (For the spark section)


And the dual map sounds like something to look into , could start with exact mirror maps and then trim the cylinders using my wideband in the #1 then equalising the afr in #2 . I am putting a O2 bung in every primary header tubes for fine tuning and one after the second collector of my 4-2-1 header for everyday tune.

Thanks

Peoplecanfly2 wrote:Only thing to confirm now is that i dont need the 36-1 trigger paired with the EDIS module . Trigger talks to the MS and MS drives the coils and his advance , thats it? (For the spark section)

It really is that simple. The association of EDIS with the MS family dates back to the early days when there was only a single ignition channel - the original MegaSquirt was designed with big silly cage engines and their distributors in mind, after all ...

If you're going to run dual fuel maps, you might consider a second WBO2 sensor. The Spartan by 14Point7.com is an integrated sensor + controller, and runs $105 each.

dontz125 wrote:... you might consider a second WBO2 sensor. The Spartan by 14Point7.com is an integrated sensor + controller, and runs $105 each.

+1 on the Spartan, I got the $125 CAD detachable version, so I could change the sensor, and if it was no good, at least I had an O2 sensor!
($146 CAD shipped & £24 taxes to the UK).

It just landed the other day, great product and it really is great value for money. The TechEdge stuff I have on the dyno is good too, but I'd thought I'd give 14point7 a try, as they have been going for so long too, and the reviews seemed positive.

Mike

Great! The install is gonna be cheaper than i thought , just the EDIS module connector runs for 60USD+ship.... And means less parts to hide in the bike , now i have to find a very compact fuel pump... I found a MSD pump wich is rated at 45gph (i dont need to feed 500hp..) but the body is 2" dia , i wish i could find a smaller inline pump. Too much flow will heat the gas and draw too much amps for my 1975 charging system...

Wow thats a pretty good deal!! I have the basic Innovate kit i used on my previous MS install on another projet. Car is sold and the engine sits in the garage so i will throw it on ze bike , anyone knows if MS will ever just read them straight without a controller?

Peoplecanfly2 wrote:anyone knows if MS will ever just read them straight without a controller?

Almost certainly not. WBO2 sensors, for all their simplicity as a device, are actually very involved to operate and interpret. Most aftermarket WB controller vendors do nothing else - it's too specialized.

That said, the Spartan controller is built into the connection, and all you're facing is four wires that you hook up like a NB.

I forgot to say the price included a Bosch LSU 4.2 and controller, with the controller only being $75 CAD. They also do OEM $40 controllers too, that are tiny, and can be integrated into an ECU case. I quite like the look of the 14point7 $199 CAD iDash too and the EGT stuff.

If your concerned about your fuel pump running all the time, why not fit a PWM fuel control system, this way it doesn't need a return, and only pumps what you need. You might find this link useful

Obviously using PWM fuel control is more expensive($100-150 depending on cost of fuel pressure sensor), but it does give you a current reduction (which you need), and also avoids heating & aerating the fuel unnecessarily.