At 12:15 PM 2/20/2011, Max Wellhouse wrote:
>Spozed to be the latest greatest thing with built in capacitors to
>hold 1,000,000 watts of power.  In one of their "reviews, someone

Whee!  Ok, their claim is that by putting a capacitor into the spark
plug itself, they make available a [small] energy pool which is
discharged at the moment the initial spark ionizes the gas in the
gap, permitting an arc to form.  The total energy isn't large, but by
putting the cap right up at the spark gap they can get an extremely
rapid discharge, hence a very high intensity, or wattage, for that
very brief interval of a few nanoseconds.  After that the "spark
event" proceeds as it would have anyway.

Perfectly reasonable physics/electronics so far.  How about the
numbers?  They're claiming average 1000 amps for ten
nanoseconds.  That would mean 1000 coulombs per second for 10E-9
seconds = 1E3 / 1E-8 = 1E(3-8) = 1E-5 coulombs stored in the
capacitor; or 10,000 nanocoulombs.  Assuming breakover voltage of
10,000 volts that would mean a capacitance of .001 microfarad which
seems to me awfully high for a 25 kV capacitor in the space they show
(note that I'm neglecting various real-life things that would make
the numbers worse - I'd really be happier if someone would show where
I'd slipped a decimal and the capacitance should be a tenth or better
a hundredth what I said).  The actual of course is easily measured if
someone has one of their plugs and a cap meter.

Now, does it make any difference?  Cutting through the fancy language
they say it does, a little, and they point to some numbers they claim
to have generated and also to three magazine reviews here:

http://www.pulstar.com/pdf/PAAS_August2008.pdf

http://www.pulstar.com/pdf/dsport_march2008.pdf

http://www.pulstar.com/pdf/modified_April2008.pdf

The middle one seems the best-informed and least ghost-written of the
three, but they all show slight improvements in dyno testing.  Note
that none of the three are interested in economy, only in peak
developed power/torque.

Here's a less formal unsponsored real-world review that thinks
they're perfectly decent spark plugs but no other real benefit.

http://www.carbibles.com/productreviews_pulstar.html

Advance Auto Parts will sell you the platinum version for ten bucks
here (they also have the iridium version for thirteen):

http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_Platinum-Pulse-Plug-Pulstar_10001158-P_960_R%7CGRPTUNEAMS_1270271073___

A serious note:  It seems to me that even quite modest efficiency
gains such as are suggested by the Enerpulse people would of
necessity be accompanied by corresponding decreases in CAT
temperatures.  Am I wrong?

My impression?  Not obvious snake oil like so many other things, but
not likely to be of much practical benefit to us WBX owners.  If they
really are as good as claimed all the OEMs will be using them in a
few years, if for nothing else to allow them to maintain their
C.A.F.E. while continuing to serve the great god Acceleration.

Yrs,
David