Brother do I know your pain.The first thing I see is your hsn should be at a maximum of3.5 turns out instead of 2.5,-depending on air quality I have had to run mine 4 turns out.3.5 should be the max,cen also instructs to set hsn at 3.5-2.5 is way to lean.Also I have learned over time that these engines do their best with 15% nitro.You can take this advice to the bank.All About Fun is probably gonna come on here and try to disputue this entire post[:@]but its okay.I have been through a lot with these engines and if I dont know it,I WONT SPEAK IT[:-]Youre right on with the glowplug.Run low nitro content.These motors are famous for heating issues but can do very well if set up right.Good luck