Tempest fine vs massive w long electrode

[RLCarter]

1 hour ago, PilotCoyote said:

Yes, at least in my A2D I can. You also get the benefit of having your compression ratio raised by 0.002.

With this new found compression does that mean I can crank in more timing to get the FULL benefit? 

[bonal]

Pulled them plugs was 3/4 on the leads so REM is correct fit.  Number one was a little oily and a couple AP's at LASAR took a look and said they'd seen far worse and didn't think was bad enough to cause a bad misfire also pointed out the electrodes were a little out of round indicating it's time to replace them anyway.  I'll  have to review the logs to see when I installed them can't be more than a couple hundred hours on them.  Went with the REM37BY so hopefully will improve this occasional issue.

Thanks for all the replies 

[cferr59]

On 7/27/2020 at 2:04 PM, bonal said:

Still having occasional plug fouling even with very aggressive leaning on startup and taxi.  Looking to replace with either fine wire or possibly long electrode massive.  Would naturally  prefer to spend the much lower cost for the massive any experience with these would be appreciated.  Also looking at the application table there is a few options for the o360 a1d not sure which is correct part number.

Suggestions and advice would be appreciated 

I have Tempest UREM38S fine wire plugs in my O-360-A1D.  I have never fouled a plug in 80 hours I have flown the plane.  They were installed by the previous owner so I don't have a comparison basis for another plug.  Fine wires seem expensive, but last a lot longer than a massive electrode plug, so the total cost over time doesn't seem that different.  

[bonal]

On July 27, 2020 at 12:45 PM, MB65E said:

REM37BY in the tempest or champion variety work really great! They don’t last as long as the fine wires but burn clean and are cheap. 
double check your spark plug lead size prior to ordering. 
I had all BY plugs in my engine for awhile. Switched to all fine wire to see what the rage was about. Bottom plugs started to fowl. Switched bottom plugs back to BY plugs. Problem solved. 
-Matt

Spoke with Dan at LASAR and he said the extended BY massive are a good choice also Matt above seemed to have good luck with them so that's the way I'm headed.  Existing tempest  REM38E had only about 150 hours on them so yes they don't last as long but fits my fixed income better.

[stevesm20b]

I switched over to the BY plugs in my O-360 and it ended fouling problems and ran smother.

 

[Pasturepilot]

I went with BYs on the bottom a few weeks ago. They certainly load up a lot less now. Figuring on fine wires up top next year, then rotate them to bottom once the BY's start to wear, and run fine wires in all positions from then until overhaul. I'd have gone with fine wires all around, but I'm minding my pennies right now. Pandemic and all - haven't been to work since March.

A side note, for doghouse-equipped Mooney owners: I noticed at annual that my spark plug socket wouldn't fit the spark plugs installed, and for some reason the ignition leads were pretty tight against the doghouse roof. I scratched my head and wondered how in the world something like that had changed in the years since I had been away. 

What HAD changed, is someone had installed Tempest spark plugs. The barrel/top insulator is just a tad longer than the champion spark plugs. In any other make of aircraft, it's probably a non-event, but on my C model it had the leads pushed up against the doghouse. I had one plug that had to be replaced and I just grabbed a Champion from my local supplier. Once I had the two side-by-side the difference was obvious. a UREM40E and a REM40E might be interchangeable but they're not identical.