Glow Plugs ??

[D__I__A__B__L__O]

Hello,

Anybody got any decent knowledge on glow plugs !!! I understand what the plug does etc but whats the heat rating about ?? I have had a Savage 21 for about 5 years now and have always run 25% fuel and medium heat plugs. Im going to get a Savage X 4.6 and want to run it on 20%, my issue is what plugs to use, do you use different plugs depending on your type of use ?? If your going for speed or climbing etc ??

Cheers

[slartibartfast]

the rule of thumb for glow plugs was:-
cold plugs for fast running engines i.e. cold plugs have thicker elements.
and
hot plugs for slower running engines, hot plugs have thin elements and often have idle bars (a piece of metal welded across the hole.

not sure about buggy engines but chances are you'll want something in between.

[Space Kid]

Stick to HPI plugs for that engine, No 4's of 5's i think?

[bramley]

My engine (an STS .28) revs to about 38,000 iirc, I've been running it on a medium plug (I think) and since crossthreading the plug in the head I now have a replacement head and need a new glow plug.

Should I stick with what worked before or change and if so what sort?

Thanks

[D__I__A__B__L__O]

Cheers all, I have decided with the ride I am going to stick with the HPI plugs, hows the HPI fuel ?? Any experience of it, guessing its gonna suit the savage !!!

38k rpm, damn thats high. they all like that ??

[slartibartfast]

[quote=DI__A__B__LO]Cheers all, I have decided with the ride I am going to stick with the HPI plugs, hows the HPI fuel ?? Any experience of it, guessing its gonna suit the savage !!!

38k rpm, damn thats high. they all like that ??
[/quote]
not sure about the fuel.
but 38krpm is bloody high!
i think only the modern race engines do that kind of RPM, the aero engines run between 8krpm and 16krpm although some of those go higher in the racing scenes

Paul

[bramley]

Page 2 of this document http://www.stsrc.com.tw/download/21%2028%20engine%20manual%20v3.1.pdf  says "close to 40k rpm"

BTW - to the other guy with a savage, are you registered on www.savage-central.com? There's a decent one page guide to glow plugs on there, and it confirms the plug I've been using is a medium-cold which worked fine so I'm sticking with it for now. I'm going up from 20% fuel to 25% though, so have to put another shim under the (new) head.

Then I can break something else, probably the diffs next...

Edited by bramley on Thursday 18th October 19:58