Phil;

Maybe you missunderstood...I have nothing against electronic VRs...in fact that is one of the BIG advantages of modern alternators. What I seriously question is the use of ADJUSTABLE VRs...mostly it's for people who blindly believe that if bigger is better, then more voltage is better too...if fact, it probably masks another problem in the system. The way things are wired up.

The problem of blowing bulbs is an interesting one which (without seeing the car and taking some voltage measurements) I might explain by stating the response time of an electronic regulator is faster than a relay unit, however a voltage spike problem MAY have been exaserbated by where (electrically) the relay and lights were powered from. A lead-acid battery is a very effective voltage clamp due to its low impedance...which means: It will not allow the voltage across its terminals to get much higher than 13.6 (that's one failure mode of a battery...if it does, it means a high internal impedance so maybe it's time for replacement). Therefore, any voltage sensitive load must take its power (with heavy cables) from the battery terminals...the further away, and the more other load currents are combined in the cables, the more voltage can be affected by load-shedding and other spikes.

The best thing one can do to assure that no voltage surges occur in the system and kill bulbs etc. is as simple as checking the battery occasionally, and keeping all connections clean and tight! In your case, installing an electronic regulator likely didn't cure the voltage spiking, but by working on the system you may have cleaned up and improved a marginal connection which did...yes, it could be as simple as that!

...and if your car starts right up after sitting for six weeks, great! It means that your charging system is fully charging the battery as it should.

Cheers