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Superior engine and UREM37BY

RedRaider94

Active Member
Wanted to get some thoughts. I have a Superior XP-IO-360-B1AD2 and some folks have recommended the UREM37BY plugs over the 40E plugs I have been running (for the slick mag - running IK27 with the light speed).

On the Tempest chart, they do not show any plugs acceptable for Superior engines except the 40E.

Can I and should I run the UREM37BY in this engine or not a wise idea? I hear they foul less but is there any other benefit over the 40E or just stick with the 40E?

Thanks!
 
I like the fine wires, not as prone to fouling and last a long time..
UREM38S is what I use.
 
Walt, I guess my question is whether there is any issue with using something other than the 40E in my superior engine? I got concerned because Tempest doesn?t show them as approved so is it possible I might mess something up or will they work fine in my engine model? They don?t show the 38 fine wires as approved either.
 
Walt, I guess my question is whether there is any issue with using something other than the 40E in my superior engine? I got concerned because Tempest doesn’t show them as approved so is it possible I might mess something up or will they work fine in my engine model? They don’t show the 38 fine wires as approved either.

The 38 and 40 are basically interchangable, the 38 is one range cooler than the 40 is the only difference, the 38 is pretty much the standard plug in the 360 series engines.
Have no idea why Superior would only approve the 40 unless they tend to foul plugs more than any other 360 out there?

Edit: When all else fails, found this in Superiors MM:

Consumables:
Spark Plugs 5/8”- 24 Thread
Unison Industries UREM40E (Massive)
UREM38E (Massive)
UREM38S (Fine Wire)
UREM37BY (Projected Nose)
ChampionAviation
REM40E (Massive)
REM38E (Massive)
REM38S (Fine Wire)
REM37BY (Projected Nose)
 
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Thanks Walt - that helps a ton. Not sure why Tempest doesn?t list those as acceptable. I will give the fine wires a try as you suggested.
 
37BY's are my plug of choice if not converting to automotive plugs and wires running off a mag.

I started running 37BY a number of years ago and never looked back. The 37BY is my plug of choice unless auto plugs are used.
 
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UREM 37BY plugs in Titan engines

The 37BY spark plug was developed originally for Lycoming O-235 engines that tended to fowl plugs, particularly in flight school environments. The projected electrode design did help alleviate fowling. We at Titan engines often supply our engines that have piston compression ratios of 8.5 or less with them if the customer chooses magneto ignition, Of course, we supply our Bendix magnetos as the first choice. We do have Slicks as well. We have experienced a slight power increase using the 37BY plugs. For higher compression engines ( 9.0:1 in the Titan 340 and 9.6:1 in the Titan 370) we use the regular 40E massive spark plugs. The 38S work fine in those applications too.
 
Fine Wire Plugs

I've recently moved my RV8 with O-360AIA to an airport that requires a lot more taxiing. And I'm apparently experiencing more plug fouling. If I want to change to fine wire, is the Tempest UREM38S the plug I should be using.
 
The 37BY spark plug was developed originally for Lycoming O-235 engines that tended to fowl plugs, particularly in flight school environments. The projected electrode design did help alleviate fowling. We at Titan engines often supply our engines that have piston compression ratios of 8.5 or less with them if the customer chooses magneto ignition, Of course, we supply our Bendix magnetos as the first choice. We do have Slicks as well. We have experienced a slight power increase using the 37BY plugs. For higher compression engines ( 9.0:1 in the Titan 340 and 9.6:1 in the Titan 370) we use the regular 40E massive spark plugs. The 38S work fine in those applications too.

James, my Titan O-340 (9.0:1, carb) shipped in 2014 with 37BY's. Should I not be running those now? Why did the 9:1's stop shipping with 37BY's?

Can't say I've experienced any bad behaviors during the 350 hours I've run it so far, aside from a single random lead bridge forming on one plug in flight.
 
37 BY spark plug

The option to use the 37BY's is an economic one as well as performance. They cost less and work well. Sometimes when quoting the engines and configuring for a customer, I don't remember to mention them as an option. They are just that optional spark plugs for the engine. You can also use the
38's or 40's.
 
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