TheOtherSide

I've heard lots of different stories... so I thought I'd ask and see what answer I get.

I have a Savage X RTR... stock motor. What glow plug should I use with it? I use 20% fuel.

One RC Store tells me to use the Real McCoy MC-59 plug (which I'm using right now as the original one just died the other day)

Another RC Store tells me the ONLY glow plug to use is the O.S. #8.

I have both... never put in the OS#8 yet...

Someone clear this up for me... I'm not a racer, just want to have fun and play around. Best results would always be desired!

Thanks in advance!

SpikeX

I use HPI R3 plugs in my Savage X. LRP and Rossi R3 plugs are also great too. I have never had any problems with them. I run 25% nitro.

JayC1968

My Feedback: (3)

The McCoy mc-59 is a long plug with a hot element. It's designed for use with low to medium nitro content..
The mc-59 is a HOT plug

The OS #8 is a medium/hot plug and is medium length..

Note:... The McCoy MC-8 is the equivelent to the OS #8

Rule of thumb is the lower the nitro content the hotter the plug

10-15% =Hot
16-20%=medium
25-30%-cold

Another rule of thumb is...

Use a hot plug with low nitro (less than 16%), and a cold plug with high nitro (more than 25%).
If you remove the glow starter from you idling engine, and notice an immediate drop in RPM, you may need a hotter plug or more nitro.
If your engine has a tendency to backfire a lot, you may be using a glow plug that's too hot, or you may need fuel with less nitro.

JayC1968

My Feedback: (3)

Hope that helps ya

TheOtherSide

So would you say that I"m good with a MC-59 with 20% fuel?

Thanks for the info!

SpikeX

What does backfiring mean? The HPI ones I use are HOT ones and I use 25% nitro as stated in my other post. Is this bad for my engine?

R.s.D

i got another plug Q
im using odonel medium hot plugs in my k4.6 with 20% nitro but its getting cold for winter should i step it up to a hot plug?

rushrtr3

My Feedback: (1)

I've been using OS A3's and getting great results.

46u

My Feedback: (3)

This may help but do not use OS plugs in it as they are to short.
http://www.osengines.com/accys/choosing-glowplugs.html

Wizz Kid

McCoy MC-9 for 20% and MC-59 for higher nitro.

46u

My Feedback: (3)

I do belive if you check you have that backwards. The MC-59 is hotter then the MC-9

Wizz Kid

i know

Flaming Tire

I use MC-59 plugs in my Savage with a sts .28 and my RS4 3 18SS. Its the best plug ive ever used.

TheOtherSide

Lotsa info coming... keep it going.

Nobody here is using the O.S. #8 I see...

Chronic

I ran OS #8s for a long time. I've been experimenting with other brands/heat ranges just to get experience with them, but the OS #8 is my standby plug. The stock .25 in my Savage LOVED that plug with 30% nitro. I know that technically it's too hot for that fuel, but that's just how it ran best. Just about all of the racers at the local track run that plug and that's where it was recommended to me. The OS #8 also works very well in my modded Mach 427 and LRP spec 2 with the same fuel.

Disclaimer: I'm not too concerned about engine life... I'm more concerned with maximum performance. I also pay very close attention to the tuning, so I can deal with the smaller margin for error. Run a med-hot or hot plug with high nitro content fuels at your own risk, don't come back blaming me if you kill your engine.

SpikeX

What does backfiring mean? The HPI ones I use are HOT ones and I use 25% nitro as stated in my other post. Is this bad for my engine?

46u

My Feedback: (3)

All I know using a hot plug with anything over 20% goes against all the recommendation of all the articles I have read like the link I posted above as well as running a hot plug in a big block. I run the recommend plugs and do not have a problem and the plugs last for 2 to 3 gallons and most of the time I change them before they go bad after many gallons as maintenance.

Size matters to glow plugs. What size is your engine? A .12? .15? .21? Big engines have more mass and retain heat better. Smaller, lighter engines don't, and need the help a hotter plug can offer.
The smaller the engine, the hotter the plug.

What's the nitro percentage in your fuel? High-nitro fuels produce more power than low-nitro fuels, but also produce more heat.
The higher the nitro content, the colder the plug.

Smart modelers tend to keep a variety of glow plugs on hand. The reason? Because the "right" plug for your engine can change with the temperature. To achieve top performance, your choice of plug needs to change, too.
The hotter the day, the colder the plug.

SpikeX

My engine is a F4.1 (.25). When I first started using hot plugs the temperature outside was about 15-18 degrees celcius. Now, here in Hamburg, in the morning there is 0 degrees C and during the day there is about 7 degrees C, so I think I will stick with the Hot ones for now.

It is strange though, because with the R5 glow plug my engine came with, the engine just would not start whatsoever. As soon as I changed to an R3 plug, it started up on the first try.

In the 2 months that I have used hot glow plugs, could my engine have sustained any serious damage. After winter, I will use R4 (Med-Cold) plugs.

Wizz Kid

all i can say is when my dad and i switched to 30% on 3 different trucks and motors, we put 59's in and it ran and held a tune twice as good as the 9's

46u

My Feedback: (3)

Changing glow plugs affects the timing, which can affect performance and the life of an engine. I have no problem with my engines holding a tune.
Bottom line run what ever makes a person happy.

TheOtherSide

Cool... I think I've got all the info I need at this time.... I'll stay away from the OS #8's... and keep with the MC-59's...

[8D]

redman1

I just started running the MC59 plug in my TNX.After
going through 3 brands the MC59 is head and shoulders
above the rest.

lonelydogg21

sorry for bringing up an old thread, but I'll throw my results in.

brand new Axial 32, 20% nitro.
MC59 runs absolutely fantastic. starts on second pull. solid smoke from idle to wfo. temps around 240-260 on 90 degree(f) days. and fast...
swapped in an OS8 as a trial. feh, what a pig. three tanks and the MC59 is back in, and needles back to where they were.

TheOtherSide

Cool... thanks for that info....

Haven't had too much time to RC this summer.... so I still have a bit of 20% to burn before I go to 30%.

munro300

Check this out

http://www.maxxtraxxusa.com/Glow_Plu..._in_herre_.cfm