Spark Plugs

[kidturbofan]

Hey All'

Just tryin' to tie together a little info from the "pinging" and "high rpm miss" threads.

As I stated in a previous post, I noticed the the motor started pinging right after I installed Champion RE14PLP5 platinum plugs. Thanks to all who chimed in with info about the platinum plugs running hotter, leading to preignition in the high-temp, high-pressure world of a turbocharged motor's combustion chamber.

I talked with a tech guy from Champion today, and he told me that their regular non-platinum plugs, RE14MCC5, have the same heat range as the platinum ones, which I believe is indicated by the "5" at the end of the part number. This make me wonder why, if two different plugs have the same heat range, one might cause the ping and the other would not?

I was wondering if anyone knows the heat range of the OEM plugs from a Mopar part number? The ones I pulled out of my motor where Denso, I believe. I'd like to find a plug that's a little "colder" to help eliminate this issue in the future.

[:I]

[MX-5]

All PTs, including the turbo use Champion stock number 440 copper plugs. They are RE14MCC5 plug number.

The reason the copper cools better in the same heat range in because the tiny platinum tip is made to run hot enough to "self clean".
The copper plug naturally runs cooler.

There is a single platinum plug that's one heat range colder. Stock number 3032.
The standard copper #440 plug is perfect for the turbo PT. It never fails to ignite the fuel under normal operation.
I use the #440 with my 115hp nitrous setup. I'm the guy who got the #7440 RE14PLP5 double platinum plugs to market. The old-timers here may remember that it took me over a year to get Champion to market those.

[Ptturbine]

Champions really are garbage, but they work in this setup.? Platinum and the NGK double laser platinum are too hot and have too fine a point for nitrous use.