Tempest Fine Wire Model for Conti IO-550-G

[Jeff_S]

Hey all,

I am working with Tempest to get the set of 12 fine wire plugs for my IO-550-G that I picked up at the Mooney Summit.  On the application chart, there are two models listed for this engine:

-URHB32S and URHB36S

I quizzed the Tempest guy as to the difference and which one to get. He said the difference is how hot they run, and since Conti engines tend to run hotter he suggested the 32S but that I should check with my A/P to be sure. So I've checked with both my A/Ps and neither one of them had a clue that there even was a difference, or which they would recommend.  One of them suggested that he'd always want a hotter plug, while the other was noncommittal.

So, open to the group...anybody who's put fine wires on the IO-550 or similar, do you remember which version you used or do you have any advice/recommendations?

Thanks!

[jerryg324]

I swapped earlier this year to Fine Wires and installed a new wire harness. Couldn't be happier with the "32S"

The heat rating of a plug measures the ability of a spark plug to transfer heat from the spark electrodes and insulator nose to the cylinder and engine cooling system while resisting carbon fouling. TEMPEST® Aviation Spark Plugs are available in a range of heat ratings to meet various engine and operational requirements. The use of terms “hot” or “cold” in reference to spark plugs is often a source of confusion when selecting the proper spark plug for an application. For a given engine series, hot plugs are usually specified for the lower horsepower engines and cold plugs for the higher horsepower engines. The terms actually refer to the plug’s ability to dissipate heat. By definition, a cold heat range plug dissipates heat more rapidly. Likewise, a hot heat range plug has a slower rate of heat dissipation. The primary factor in whether a plug is hot or cold is the length of the insulator assembly core nose. Hot plugs have relatively long insulator noses and, therefore, a long heat transfer path. Cold plugs have relatively short noses and thus transfer heat more quickly. All other parts of a part number being equal, you can tell if an TEMPEST® Aviation Spark Plug is hotter or colder heat range by the numbers in the middle of the part number. For instance, comparing a UREM40E with a UREM38E, the UREM40E is a hotter plug because “40” is larger than “38”

[Jeff_S]

Thanks Jerry. You’re the second person who suggested the 32Ss for my setup...the third if you count the Tempest guy himself. I’ll order the 32s!

[LANCECASPER]

If your oil consumption is up a little go with the hotter plugs (36S). If not go with the cooler ones (32S)