I have been thinking, ( Yes, please stand back, way back).
I'm using the 1835 cc VW engine with a Slick mag, ( have you looked at the prices lately ? ) . Since I fly over some very rough terrain where there is no place to land except in the tree tops, I have been wanting dual ignition for the engine. But the kicker is, I don't have an electrical system and don't want the weight of one. I do use a small gell cell model airplane starting battery to power my handheld radio, elevator trim servo and oil temp gauge. So stand back, here is my idea.
Thinking about using GP's low height fixed timing secondary ignition system, ( http://www.greatplainsas.com/cat2014I1.pdf ) . Since I was thinking of just using it for take-off and landing and when over the worst of the terrain to make the battery last as long as possible and if the Slick mag went out quickly turning the secondary ignition on before the engine stopped. But since I'm an old fart and don't do anything fast, I was thinking of something else. I have some differential pressure sensors that I can use to sense the manifold pressure and make a circuit that will turn on the secondary ignition when the manifold pressure get down to a set limit, say 15". So I will have a toggle switch to turn the secondary ignition on (with a indicating LED) after start up with the mag, and if at cruising manifold and want to use the dual ignition turn it on with another toggle switch ( with another indication LED), but with this switch off the secondary ignition will come on automatically anytime the manifold pressure gets below the set amount.
What do you think?
Dan
I'm using the 1835 cc VW engine with a Slick mag, ( have you looked at the prices lately ? ) . Since I fly over some very rough terrain where there is no place to land except in the tree tops, I have been wanting dual ignition for the engine. But the kicker is, I don't have an electrical system and don't want the weight of one. I do use a small gell cell model airplane starting battery to power my handheld radio, elevator trim servo and oil temp gauge. So stand back, here is my idea.
Thinking about using GP's low height fixed timing secondary ignition system, ( http://www.greatplainsas.com/cat2014I1.pdf ) . Since I was thinking of just using it for take-off and landing and when over the worst of the terrain to make the battery last as long as possible and if the Slick mag went out quickly turning the secondary ignition on before the engine stopped. But since I'm an old fart and don't do anything fast, I was thinking of something else. I have some differential pressure sensors that I can use to sense the manifold pressure and make a circuit that will turn on the secondary ignition when the manifold pressure get down to a set limit, say 15". So I will have a toggle switch to turn the secondary ignition on (with a indicating LED) after start up with the mag, and if at cruising manifold and want to use the dual ignition turn it on with another toggle switch ( with another indication LED), but with this switch off the secondary ignition will come on automatically anytime the manifold pressure gets below the set amount.
What do you think?
Dan