BloomAce

My Feedback: (2)

What is the best glow plug for a TT 40 Pro for 424 racing?

Thanks

Bill Vargas

My Feedback: (5)

McCoy #9 always worked the best for me when I flew 424 back in the day


BV

Scorpion Racing

I like the K&B HD plugs. (part #7310) Same plug as they used in the ducted fan engines years ago, and will really take a beating and not break!

djlyon

OS #8 , mccoy #9

fizzwater2

My Feedback: (61)

I've been having good luck with the K&B 1L

ChrisAttebery

My Feedback: (15)

If you want a plug that'll last forever and make decent power the McCoy #9 and K&B HP plugs are great. I have run them up to 60% nitro and .90cu/in. They are heavy duty colder plugs though. My opinion is that you can probably make more power using a hotter plug that will advance the timing a bit more and help burn all of the fuel. The more fuel you an burn the more power you will make.

For instance, on my OS 46AX club racer I am running a 9.5x6 APC. With an OS #8 plug I get decent power and decent idle. If I switch to an OS A3 plug I have to richen the needle about 1/4 turn and it will idle much lower and smoother. If I switch to a HP or #9 I have to lean the needle 1/4 turn or more to get it to run. The idle and transition are much worse in comparision. The RPM numbers will be close, but I believe that the hotter plug will be faster and provide more lubrication in the end.

Scorpion Racing

I have found in 424 I will destroy an OS#8 in 1 heat, ... or LESS. The element will solder itself into a lump, or just melt away! The cold plugs allow me to run the rpm I want, and not blow up the plugs. As far as idle, the idle screw is glued in at about 1 1/2 turns from falling out, so there is no idling! Engines for racing 424 are set up for full throttle only, so if you want to sport fly it, forget everything about the plugs. A bladder tank is a very important part of this equasion too; without one, you will risk a lean run and that will take out a plug every time. [:@]

s-10promod

I've had very good luck with the Fireball's. Look on the online auction site, you won't find a better deal anywhere! I can usually fly an entire race with the same plug unless I get greedy on the needle.

fizzwater2

My Feedback: (61)

Which fireball- standard, cold, etc?

BloomAce

My Feedback: (2)

Thanks for all the ideas guys. I think I will try the McCoy 9 first and go from there.

s-10promod

The Standards are all I've used