no it doesn't need to be marine grade, no such thing really. The traditional oil filled or epoxy filled coils is what they all are.<br /><br />Yes you can use it with your existing coil.<br />All that would happen is you wouldn't achieve maximum possible spark than with using their brand coil or other quality coil of same performance. When I first bought the ignitor 1, I used my original coil with no problems then upgraded that later on. A warning watch out for coils advertising high performance for $30-60. I bought a no-name one from jcwhitney which was junk, it was a 60k volt one for $39. I figured less expensive, more than the 40k volt flamethrower, good deal. Motor would sputter after 5 minutes running at 3k rpm. Coil would overheat and temporarily fail till it cooled. Put my $10 coil from points ignition back in an no problems till I finally got around to buying the flamethrower 1.<br /><br />what you also have to watch out for is the internal resistance of the coil. Lower internal resistance, such as 0.6 or 1.0 ohms versus 1.5 or 2 ohms, will flow more current (power) and in the case of points would cause them to burn out quickly. If you flow too much current, it'll burn out any electronic ignition module also. This would happen for instance if you used the flamethrower 2 coil at 0.6 ohms with the ignitor 1 instead of the flame 1 coil at 1.2 or 1.5 ohms which the ignitor 1 was designed for. For this reason, buy the ignitor 2 and then you can upgrade to almost any coil safely later on. Plus the ignitor 2 has more features and just worth it in the long run.
