Patriot

It is obvious that highr nitro in a four stroke engine provides better performance, but how does the higher nitro content affect the engine and exhaust temperature? I assume, that with better performance, the temp is hotter, but was just wondering whether or not it is a significant differance.

The reason I ask is that I have heard my Enya 155r will run well on 0% nitro. They just don't seem to be very picky about fuel. But it doesn't have quite as much performance. If it will run cooler, and have a lower temp to prevent damaging my homemade exhaust, then I'd like to stick with it. I just don't want to fry my exhaust with high nitro fuel.

Patriot

dmgadway

I just tryed a new fuel in my saito 180. My standard fuel is wildcat 20%nitro/20%synthetic oil. My engine produced about 9400 rpms with a 17x8 prop. I changed to a 10%nitro/20% oil sig fuel(50%castor/50%synthetic). I lost about 300 rpms but the engine runs noticably cooler. For what its worth, I don't know if its the castor or the reduction in nitro that alows it to run cooler. The needle setting range was much wider with the 20%nitro.

Patriot

Concerning the muffler I am using, I used some JB weld to seal up some of the parts, and I am hoping that it will run cool enough on 0% without damaging the weld. I know that 15% will give a good increase in performance, and some say the JB weld will hold up, but I want to minimize how hot it gets.

Patriot

Sport_Pilot

If you up the nitro to cause detonation to occur then the temperature will be higher, if the compression is low enough to prevent detonation, and with the correct plug, then high nitro run rich of the highest rpm will have a cooler exhaust. Just as our glow engines have a cooler exhaust than gas engines, but would have less performance if we switched to gas.