I just purchased a 240Z and it has both a Pertronix Ignitor and a MSD 6AL. I've owned other 240Zs and used the Pertronix system with just a regular coil. What's the advantage (if any) of the MSD 6AL and the Pertronix? To be honest ... I'm not even sure the MSD 6AL is even hooked up.

The 6AL has a rev limiter. One way of checking if it is hooked up would be to try to rev the engine past the limiter. There is a little "pill" as MSD calls it plugged into the side of the MSD box that shows what the limiter is currently set at.

The advantage of MSD is more power, less plug fouling, better mileage, etc. A buddy of mine did back to back dyno tests with stock Nissan EI and MSD and found an 11 whp increase (on a 510 no less) with MSD vs without. Pertronix gets rid of your points, so it too is very beneficial to have.

I agree with Jon, I have never bothered to dyno the car with and without the MSD but I find that the car idles better and has better throttle response. Plugs read better when you pull them out for change etc...

ditto what they said.....I've had them in my 240 (3.2L NA motor) for over 6 years and a lot of hard driving. No problems, no issues, no worries.....