[rxstephen]

Hi,

Thinking about this one way, if you have not modified your car because of WI then you should run hotter plugs because the combustion temps are less. However in practice, you will have modified your engine to take advantage of the WI and will be running more advanced spark, higher compression or higher boost. In which case you run either standard heat range, or more likely a colder heat range.

I have a turbo charged rotary. Rotaries are notoriously harsh on spark plugs because they fire twice as often as a 4 stroke piston engine, and also have no intake stroke that flows cool air past the plugs. However I have been running WI for 2 years now, and have significantly increased the life of my plugs. Generally they stay cleaner, otherwise you wouldn't notice any difference when running WI. This may also be thanks to the leaner mixture I can ran.

The only gottcha with WI and plugs, is that there is a higher chance the flame can blow out, I have had to change to a different style plug and run a smaller gap to prevent missfires. Also it helps to have a mapped WI that delivers the right amount of water across the rev range.

HTH
Cheers
Stephen