fox plugs, any good?

I have been using the Fox R/C long plugs for years...they always seem to work fine for me in everything from .90 to .15 engines..... Have no idea of the "heat range" but they are good reliable and long lasting plugs...

Well, when someone comes up with a heat rating system that all the manufacturers will adopt, then it may be useful. Until then, I don't worry too much about a number other than how it relates to others in the same brand.

I have used Fox standard longs in many engines and they run just fine. My favorite all around plug is the K&B 1L. I have used it in everything from GMS 32 to YS 91.

I'm running a Fox long glow plug in my GMS .47 and it's running embarassingly well. I'm told that the GMS engines are the same as the TH house brand motors, but I honestly don't know for sure.

Nothing beats an OS plug, but the Fox plugs come pretty close. I prefer the one that has the idle bar, but the standard long is OK too.

The idea of specifying a heat range on glow plugs is a joke. What you should to is monitor the color of the filament and make sure you use a fuel with the proper oil content. Regarding nitro content, I use 5% since I don't feel much performance improvement with higher content.

Ciao,

Mr Akimoto

Has anybody really done a scientific experiment on the performace differences among varying nitro contents? I agree with Mr. Akimoto, i think it's simply the placebo effect people get knowing they spent the extra bucks on "better" fuel.

Secondly, OS #8's are so popular because they have no competition. Try and find another Long plug, medium heat, w/o idle bar.. Hard to find...

Thirdly, a question for Mr. Akimoto, you've told us what the filament should not look like, how about telling us what it should look like.

Seany1124:

It should appear as something between the two extremes of dark brown and frosty white:

Mine have a sort of worn metallic look.

Ciao,

Mr Akimoto

Those are relatively meaningless when compared to other brands. They are OK when comparing to same brand plugs. What is needed is a quantitative measure of heat range for plugs that all manufacturers can use. Of course, it will never happen!

The reason you don't see much difference in nitro levels is because you don't use engines designed for higher nitro. If you ran a four stroke, you would instantly notice the difference between 5% and 15% nitro. Idle would be smoother and more consistent and top end would be much stronger. Transition is usually a lot cleaner as well. I ran the typical YS 20/20 blend in my four strokes for sport flying and 40/20 for racing.

OK, Paul, try this one:

Is that better? :-)

Not really because the vague terms of hot,medium and cold are used but then later in the article, a plug that was termed hot is called medium (OS #8, etc)

This is not a standard that can be tested and used to grade plugs.

Geoff:

That's pretty good and useful information, and I believe it's the best summary you'll find regarding glow plugs. However, to find out what your needs really are, you'll just have to experiment.

For me the OS glow plugs, #8 and A3, last forever, but I really like the Fox plug with the idle bar. My engines just seem to throttle up better - could be my imagination? I also like the idea of the Fox Miracle Plug that can be used in both 2 and 4 stroke. One day I'll check it out.

Ciao,

Mr Akimoto

One seemingly obvious missing point in this thread is the simple suggestion that "When all else fails, read the instructions." In other words, start out by using the manufacturer's recommended plug -- then, if you are still experiencing problems, try some others. BTY, I find the Fox Miracle plug to be an excellent plug, and suggest it when all else fails -- especially with older somewhat worn engines.

Cheers -- \_________Lyman Slack________/ \_______Flying Gators R/C___/ \_____AMA 6430 LM____ / \___Gainesville FL_____/ Visit my Web Site at

I like the Miracle plug as well but I find it a little too hot for many newer two strokes. Its original intent was for four strokes which need a lot more heat retention (not necessarily hotter). My go-to plug is the K&B

1L when I can't resolve problems with tweaking. I know that almost any sport engine made will run on that plug. Maybe not at the absolute peak, but good enough to make sure that it isn't the plug causing the problem.