MoTeC Global Forum

Hi,

I have always run waste spark ignition with blown methanol. I want to change to Motec ignition, what is the advantage of sequential ignition (CDI 4) over waste spark (dual channel motec CDI)?

If I use CDI 4 I will need either single tower coils or COP. I need the biggest spark energy available running big boost and methanol, which is best?

Can you give some millijoule examples of the coil output you suggest, what can I expect?

Thanks for your help.

The benefit of sequential firing using individual coils over wasted spark are below:
-Big charging time is possible to coil spark between a fire event to next event (if you have one coil to fire multiple cylinders, in very high rpms and depending the number of cylinders, you can loose charging time during events)
-Higher spark plugs life; remember that each spark event, you loose material from central and ground electrodes. In wasted spark, you will always wear one plug without need (firing in pair, but just one cylinder will combust).
-Higher life of coil; if you have one coil to each cylinder, each coil will work less times than one coil to fire multiple cylinders


Regards,


Matheus

Although Motec CDI4 is good, for drag racing I would seriously consider M&W Pro-Drag4 unit. Crane LX92 coil is a known performer in hi boost methanol and hi boost ethanol use.

How many cylinders ? What sort of rpm's will you be using ? ie, how long do your coils have to charge ?


The IGN-1A coil is highly recommended, and doesnt require any external ignitors or require long dwell times to produce a great spark.