It's time for new spark plus in the Comanche (O360A1A). The Champion plug chart shows that The REM38E is the recommended plug but the REM40E is also ok. Currently we have the REM40E. They were there when I bought the plane. My understanding is the "40" plug runs a little hotter that the "38" but is there an advantage of using one over the other. From what I have read, the 40 is a little less prone to lead fouling but we have not had an issue with that, but of course that may be because we are currently using the 40's. So are there any other advantages/disadvantages of one over the other?

I have posted this question on another forum but the response has been somewhat tepid. I'm hoping to get some advice and info from the group here. I know some of you are partial to the fine wire plugs but we have decided to stay with the massive for now.

Thanks
Greg

Extremely happy with fine wire vs the 38 we had in the past

I use 40E's in my IO540 on my Comanche. My suggestion - if they run well and do not foul, why change? I also changed to Tempest 2 years ago. Newer design, lower cost - but mainly because the nickle plated plugs do not rust as quickly.

pat, are you using tempest fine wire ?
Thanks Tom c. PA 30C

Tom,

It has been 3 years, I can't recall. Does show $78.75 each in 2009 so I suspect Champion

Pat
Champions are now 93.75 ea tempest 49.50 so much for 3% inflation
pat do you have gamis ?
Tom c.

Tom,

Yes I put in GAMIs when I overhauled the engines in 2005. In the IO320 it didn't seem to make much difference ... but the engines were running well before overhaul so its hard to tell. We didn't have the JPI to do before and after measurements.

Pat,
Thanks for your input I think I'll go with tempest fine wires I'll post the
results after a while.
Tom c.

Tom,
I've run fine wires (Champion) for many years now and cannot say enough good things about them. They last forever....I run them 1000hrs then
give them to friends who run them some more....! I feel certain you will be happy with the fine wire plugs
Oh, I run IO-320's and an O-235 and previously an O-360.
Steen