ORIGINAL: 46u
I normally end up changing mine at about 3 gallons as routine maintenance as I only have very few go bad. If you tune properly and use good fuel they last a long time.
how do you get that long out of one glow plug?? i run OS no.8 and a5 plugs with 20% nitro AT RACING brand fuel, which brand of plug do you use?i'm lucky if i get 1-2 litres out of one plug...and yes i have tried different tuning settings and still can't get that much...