Why are the os brand glow plugs so exspensive? Is there a way to buy plugs, or a place that is good but enexspensive? It kills me to pay allmost 8 bucks each at the hobby stores. Im just useing a normal # 8 plug.

There are many good plugs out there. I like the K&B brand plugs. A little less money than OS. I was shocked at how much plugs had gone up. I'm recently back from a 10 year layoff form the hobby...... I think the last plug I bought prior to my hiatus was less than $3.

Ken

My understanding is the cost is high due to having platinum in the plugs. That is one very precious metal nowadays. Dunno if OS has more platinum in theirs than others though! Jon

That's part of it. The platinum coil is also hand fitted. I rum four strokes for the most part, you want sticker shock!!! I buy YS plugs or H-9 when I place an order. There are a lot of brands I have found that work just as well and less then half the price. I have noticed they don't last quite as long.

Look at Fireball plugs on *bay.

I have found that the Fox plugs (American made) work as well or better than most of the other brands. Their Miracle Plug is excellent for 4 stokes as well and are usually less expensive than the competition.

I have Saito, OS and Supertiger engines and run OS plugs in all. Everyone of my engines runs for gallons of fuel on the same plug, seems to me $8.00 every other year is not worth worying about. If your plugs are not lasting very long I would re-evaluate my fuel mixture settings. I have tried Fox and had good luck, they seem like great plugs as well. Just be careful, don't be afraid topay fora good plug.

Well im not afraid to pay for a good plug, especially when thats my only option when Im at the hobby store. It just kills me to know that 2 plugs is allmost 20 bucks when I buy them. Now is there a differance made with the plugs as to what kind of fuel is used with them? And I mean longevity of the life of the plug.

I also use the FOX plugs sometimes and have had good luck with them. So far I have never noticed any problem with the fuel effecting the plug {store bought}. If you tune to the lean side the plugs don't last as long. As an engine starts to wear out the plugs start to short out.

Don't know about different brands of fuel. Do know you want to be careful not to tune too lean. I always tune for approx. 300 RPM rich of peak, if you don't have a tach get one.

Generally, the more nitro, the faster you'll toast a plug.

If your engine has high enough compression to run 0% nitro and fly the airplane OK (power will be off some), the plugs will last longer, but you may need to switch to a hotter plug and tweak carb/idle setting with 0% nitro.

I Use Fox plugs in all my engines with great success. Helps to get them from Tower six at a time. I just include them with other stuff when I'm ordering.

BDZ65 nailed it. If you're using more than one plug a year on a plane you fly regularly then something is wrong.

K&B, and Fireball are old standbys.  The Fireballs had some bad seals for many years but the cool plugs took the high nitro and high compression well.  We epoxied the seal before using them.  There are Merlin plugs, O'Donnels, Fox and Rossi, and likely more that are likely OK too. I had bad luck with CS plugs.   Most plugs are long or short.  Since OS came into the picture they make it necessary to take the head off to check for flush in the inside of the head because they are in between the long and short size.  I put 2 washers on the long plugs on the OS motors just to use up my long plugs.  Just pick hot med. or cool for your purposesand most plugs are pretty good.

I have no problem with $8 for a plug. I don't know what I am doing right, but my plugs last forever. I have OS and Enya plugs that have be in use for years and been through many gallons of fuel and they are still good. I wear out engines faster than I wear out plugs. The only bad plugs I have had in 10 years of flying were when I accidentally connected one to 12 volts and when a bearing cage broke apart and the shrapnel crushed a plug's coil.

We were using 80% nitro and raising compression for more performance.  A new plug for a race or record attempt etc. so $8 a plug as well as performance mattered back then.  Now things are limited to 10% nitro so it isn't as big of a deal.  A sport engine is more geared towards a good idle and longevity.  Most plugs are pretty good now if the heat range is chosen properly.  Heat ranges vary by manufacturer as well, so it is experimentation.  Everyone is familiar with OS, so it is an easy choice to get the #3 or #8 because they are so popular.  They are OK, but a bit pricey.