Sun engine analyzer?

[bruce]

So I'm at an auction today and I picked up an older Sun engine analyzer for a few bucks. Anyways my thoughts on this item was to use it while running one of my engines on the dyno to watch the ignition system, not all the time just to help in diagnostics. My engines are single cyliner and the unit only goes down to 2 cylinders I would assume the my rpm indication would be off on this unit, which is not a problem since the dyno has a digital tach.

Any comment on my thoughts? Am I off "my rocker"?

[larrycavan]

Off your rocker? ....No further than the rest of the gang I'd say

It certainly can't hurt to have a look at what's going on in the spark system. What kind of ignition system is on those units? What are the rules limitations? Are those motors large bores? Can you benefit from a dual plug setup in the heads?

Just thinking outloud...

Larry C

[bruce]

I run a homebuilt crank triggered ignition using mostly GM HEI parts. I plan on testing on my dyno (when its finished) dual plugs along with various other ignition parts. I want to see the difference if any between the HEI and a standard coil. Most of our engines run a point/coil setup so hopefully the analyzer will be a good addition to my testing.

[larrycavan]

Here's a little something I'll pass along on.

On 4 cyl bikes with dual coils and 180 cranks, the coil fires both plugs at once. One just fires harmlessly on exhaust stroke and the other is firing on compression.

When they fire, one plug fires groundstrap to center electrode and the other fires center electrode to ground strap.

Now I don't have any idea if that information is worth a hill of beans to you but I thought it was interesting to note that one plug's firing path is reversed....

Larry C.

[JRM]