tips on starting w/ fuel and spark

[czb83]

Hey, I have a MS1 V3 MSnSE board that Im trying to control fuel and spark with. I have to start with both so its kinda hard. I've already spent about 30 minutes changing settings and cranking with no luck, had to stop so I didnt completely drain my battery.

I was wondering if any body had any tips on doing this. Im using direct coil drive with one coil. I'm not sure what the trigger angle. I've tried lots of numbers, basically in 5 degree increments but none give me the results I want. I've also been adjusting the cranking pulses. I played al little with VE and AE, but left those pretty much the calculated values. I'm running fixed 10 Degree ignition(time based).

What it currently does is when i first try to start is rumble like it wants to start but then dies. I can crank it again and it seems like it wont even try to start. I'm i pull power to MS to reconnect it does this again. It doesn't seem like it always has this behavior though. Sometimes if I crank for a couple seconds it might rumble while cranking. The closest i've got is i starting cranking and it immediatly reved up to like 600 rpm and quickly died. Most of the time it just sputters.

I figure trigger angle is important, but without it running I cant tune it with a timing light. Should I just like start from 0 and move up in 5 degree increments until some number to see when it behaves best? I'm hoping the calculated fuel values are good enough to get it started or close to it to narrow down things.

What about dwell settings, do these have to be very close to get it started?

One thing I was thinking about was AE. I figure when it starts to come to life its above the 200rpm i have set as crank RPM(it cranks at like 180). So does the fact that it wants to start mean that the cranking pulse widths are good and I should be messing with AE now?

Now that I can actually try and start my engine its getting excited

[thechuckster]

I'm in the same boat as you (having to tune fuel and spark at the same time) - but more info on your setup will help others contribute to this thread.

There's no point playing with AE - you just want the right Req fuel to idle smoothly and a correctly timed spark - then (and only then) shoudl you go onto tune other settings.

To get it started you should be playing with cranking pulse widths as well.

There's a good guide for dailing in your timing for MSnS with a dizzi:
-go here: http://megasquirt.sourceforge.net/extra/setup-msns.html
-scroll down to the section "Distributor setup"
-read and re-read

If you'e unsure of dwell (except you know if your ignitor is a dumb or smart unit):
http://megasquirt.sourceforge.net/extra/dwell.html

[PSIG]

Pull your spark plugs out so the engine can crank easily and ground the plugs. Remove power from your fuel pump so you're not injecting fuel. Now you can crank with less load and get your ignition set-up so you know it will fire when you get your fuel correct later. One thing at a time is easier for me.

David

[czb83]

Well, Im using dual trigge mode with two hall sensors. At cranking speeds its really hard to measure timing, but I don't know how to calculate it so it may be the only way.

The wheel is 12 teeth, not evenly spaced. There are 3 groups of 4 teeth each. Is there a way for me to measure trigger angle on an already running engine, maybe with a scope?

[PSIG]

Maybe I misunderstand - can you set your fixed angle to 10°BTDC and see that on your balancer timing marks with a timing light when you crank? The system must be able to spark properly at cranking speeds and you should be able to verify this with your light. IF it's sparking #1 at 10°BTDC like you set it, you should be able to leave it there for starting purposes or set it to -10° to use your own timing map right away if you have one loaded.

David

[czb83]

RIght now I have it set at 10 Degrees fixed. If I get someone to crank it with me holding a timing light, I cant tell where the mark is because it flashes so slow. I think next time Im going to mark with white-out or something the mark on the pulley and the 10 Degree mark, to make it easier to see when they match.

[czb83]

I marked the timing notch, and the 10 Degree window and it was easy to match it up. It actually started(after jumpering some relays), but died immediatly after. So hopefully, im set on spark and can move onto fuel. It seems there are plenty of resources on this board with tuning fuel, so I should be OK ;)