BlastinSideways12A

Question:

I built both, the VR and Hall effect circuits on the 3.0 board. The only thing that I haven't done is build the jumper to decide which circuit to use. I THINK that I will be using the VR circuit. I will be running with fuel only for a while. Is this correct?

muythaibxr

IF you're ever going to use the MS for ignition... you'll want to hook TSEL to VROUTINV, and hook the tach input to the VR sensor conditioner circuit.

You can adjust the vr sensor conditioner potentiometers for triggering off the - terminal of the coil.

Or you can just change the jumpers later, and use the normal hall input (which was originally designed for triggering off the - terminal of a coil)

BlastinSideways12A

Good, when I built the circuit I followed the steps used to trigger off of the - terminal of the coil. Changing jumpers is no problem. This brings another question, does it matter whether I use the leading or trailing coil?

muythaibxr

I would use leading if you're going to use the - terminal of the coil directly... I think others here have triggered from other wires on the trailing though.

BlastinSideways12A

Thanks. I'm starting to get all of this figured out.

BlastinSideways12A

Another question, will I need to install the diode "D2" (1N4001)? Or should I jumper it?

BlastinSideways12A

And another question:

Do I need to "populate the high current ignition driver circuit"? This seems to me like it is used for ignition control and that I won't need it.

muythaibxr

are you reading this:

http://www.megasquirt.info/ms2/V3assemble.htm

Most of your questions are answered there... you don't need d2, jumper it, and you don't need the high current ignition driver even if you are going to run ignition on the MS

BlastinSideways12A

Thats the assembly instructions I am following step by step. The part that threw me off about the D2 was that it is sometimes used.

emohn

I thought I'd piggyback this question in on this thread, rather than cluttering things up with a similar thread.

I plan on running MS on my GRM $2006 Challenge car, which will be powered by a bridgeport 13b. I'd planned on initially controlling fuel only with MS to keep costs and complexity low. My plan is to build a v2.2 MS and pick up the ignition off of the negative side of the leading coil, using a distributor to handle ignition w/ the stock s4 NA coils. Later I can add the *error board to pick up the two LM1815 circuits if I want to add ignition control at a later date. I know that it would be easier to just use a v3 board and only have to add one LM1815 circuit later on, but the low price of the 2.2 kits and the fact that a friend of mine has successfully built several of them has me leaning that way.

So my question is, is there any flaw in my logic/plan so far? Or am I way off base?

Thanks in advance for advice and for the great resource you all have already created here.

-Erik

muythaibxr

you should be able to do what you want... I personally would go for the v3 board just because it's better at keeping you from shooting yourself in the foot, but what you want to do will work fine.

jayroc

How do you plan to control the coils using the distributor? Kent Abel sells a circuit that works well for this..
http://www.rotaryx.com/index.php?a=1002&b=283

Better hurry if you want one, though. Ends in 12hrs, and I don't know if he's going to relist.

Oh, there is no means to control trailing with the circuit.. I run leading only on my "racecar" without problems or lack of power...

muythaibxr

yeah, there's no problem running leading-only... running trailing actually hurts emissions a little but helps fuel economy... (This is from one of the original rotary design docs that's posted in another thread in the megasquirt section somewhere).