Offshoreonly.com - Rapid Fire Spark Plugs

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I agree with OB.. used them two years.. less soot .. easy starts..great performance....:cool: :p

I think there fantastic!!! I switched to them 2 seasons ago, and the start ups, and no wake runs are smoother. They never fouled, and I havn't seen any black soot ever sence.:D :D

All plugs "can" foul. With today's high voltage electronic ignitions, though, most any spark plug of the proper heat range will be incredibly foul-resistant when compared with plugs in the "leaded fuel and points and condenser" days...

About the only time you will see plug fouling in a modern unmodified motor is when the plug wires, coil, or other ignition component is breaking down (failing), when the fuel mix has become horribly rich, or if the motor is passing oil into the combustion chamber.

splitfires have two electrode tips from which to spark. Completely unneccessary when the "one" you normally have is not contaminated with gunk of some sort.

Clean up idle quality? Maybe. Won't argue with that.
Give more topend HP? No way. I don't buy it.

Now, if you are comparing NEW splitfires and wires to OLD plugs and wires, then sure, I'll buy that. If you compare NEW splitfires with NEW AC's (or Champions or NGKs or Motorcrafts...) then I just don't buy into it.

Whatever you use, get resistor plug equivalents to the Merc plug.

By the way, I've got an old Husqvarna 390 with a Motoplat CDI ignition and a Bing side-float carburetor. Bring me any plug you want and I promise I can foul it for you... (Hyper, this bike was outdated before you were even born).

I ran them on my last boat. I was a 502MAg. They made the idle smooth out and I swear they added a touch more response. Black transom crap was greatly reduced. I would not hesitate to use them again.

I have run Rapid Fire #1's for 3 seasons, they DID reduce Black Transom Disease. Really no performance improvement.

454 MAG MPI.

Jan

Has anyone tried them in a HP500EFI? Thanks, Denny

So the Rapid Fire #1 is what will work in my '99 502 Mags???
These are probably available at Auto Zone or Discount Auto, Right?

I do get nasty transom soot on the platform and glass.. It's worth a try.. I know they're about $6.00 each... Man, I''ll have to pass on that case of Guinness. $