The Val

[vn5000]

If the ecu controls the dwell can you adjust how it controls dwell? ie adjust duty cycle.

[VL400]

Its all done for you automagically, maximizes dwell when you need power and less when not. Its also battery voltage compensated. Dwell is also not really applicable to CDI systems though.

[vn5000]

Ive bypassed the cdi module and coil and used a car coil.
$12p seems to have no probs running a single cyl 4 stroke wich is good.

[Holden202T]

im not suprised the pit bike struggles without the ecm, its probably getting 10 degrees everywhere!

[VL400]

Long time since this thread has been updated. The engine came out for a freshen up a very long time ago, got it all back together with a few more go fast bits and made some changes today.

Had a few things that were a problem, the biggest being the MSD ignition was causing false triggering when using the dizzy pickup. Went to a MSD flying magnet setup and it still was getting some high RPM spikes. That was when the engine came out so got back to it today. Moved the ignition module to the engine plate and used a different dizzy (holden V8 to suit a chrysler) with new(ish) leads.

Trigger.JPG (309.14 KiB) Viewed 7537 times

Overall.JPG (182.85 KiB) Viewed 7537 times

The old dizzy trigger was like this on a good day...

DizzyPickup.png (22.46 KiB) Viewed 7537 times

Fired it up using the crank trigger and was a huge improvement but still not perfect. With the new setup and the crank trigger looks like this when loading it up on the trans brake...

12P_1.png (20.26 KiB) Viewed 7537 times

Getting closer Played around with triggering the system using an frequency gen on the reluctor input of the ign module and was perfect to 7k RPM. From that testing though it showed that the camira module did stupid things if the voltage level was not right, it needed a fair bit of level but not too much. So moved the crank trigger pickup away from the trigger wheel and fired it up again which resulted in ...

12P_2.png (23 KiB) Viewed 7537 times

Finally a nice clean rev. Only issue to solve now is getting that sweet spot of just close enough to still start but runs well at higher RPMs.

[Holden202T]

good results, i wonder if thats the same issue i have with the 202 crank trigger, it worked ok but was hard to start, but then spiked when racing with it!

[VL400]

Yeah I reckon its exactly the same, just need to solve the issue now!

[Holden202T]

so your having issues with is not wanting to start now with it further away ?

[VL400]

It's a fine line between missing cranking ref pulses but no spikes when it does start, and starting ok but high rpm false triggers.

Got a few things to try before giving up on the camira module.

[charlay86]

Maybe just needs some low pass filtering to stop the voltage getting too high when the revs go up.
if it is already close to working you might just be able to move the sensor back in to where it is happy to start and put a series RC filter across the reluctor