DTMsurf

I put an SH .28 in my Savy and I am having a hard time getting it tuned right. When I get it where it seems to be running good temps are way up over 250, it hit 300 once. I have the ribbed HPI pipe too. I think I may need to pull the motor apart and RTV seal everything cause it shouldnt run like this unless its leaking somewhere. Even when it was running real hot it wasnt lifting the front end way up, just an inch or two off the ground. I think this motor should be good for more than that. I am hoping someone has some helpfull tips for this motor.

Polar_Bus

The SH .28 needs a lengthly break in period in my experiences. After a gallon of fuel mine finally started to behave tuning wise, specifically the LSN. Now it am satisfied. Power wise the engine rips! As for your comment with "temps over 250F" don't worry, temps between 240-280F is considered normal. Every engine will run a little different from day to day variables. If you find your temps close to 300F, SHUT IT DOWN, and let it cool. Running and engine at 300F is bad, and compramises engine life. If you consistantly see temps creeping over 280F, you probably have an air leak and it would be a good idea to RTV seal the engine to prevent the troublesome air leaks.

DTMsurf

Thanks, I have only got about 4 tanks through it. I was tuning it and after one high speed pass it was at 300 so I shut it down and richened it way back up. I was getting alot of 260-280 temps. I have decided to start over and set my LSN 1.5 turns out and the HSN 2.5 turns out. I wont be able to run it again for a few days but hopefully Ill get it standing up on the rear wheels soon.

Polar_Bus

Be patient, and keep at it, you have a LONG way to go before your SH starts to loosen up. New nitro guys have the idea an engine is making max power right after break-in, this is FALSE! Most engines need at LEAST 3/4 of a gallon through them befor they really start making reliable peak hp. When you pull your glow plug, and spin your engine over and feel ZERO pinch, is when your engine is making it's best hp.

supertib

also the ribbed pipe sucks, it lackes good backpressure for the fuel line, switch to a good dual chamber like the GH single stinger

DTMsurf

O.K. I have discovered many things that were causing my troubles.
1. The duratrax fuel filter I use was loose and taking in air.
2. The HPI ribbed pipe DOES suck and wont create enough back pressure to keep air out of the fuel line (the loose filter wasnt helping).
3. My throttle linkage is crap and keeps sticking. Ill be switching to the OFNA throttle mod soon.

The symptoms were that the truck was running too hot when set really rich becuase it kept getting air in the fuel line, or would starve for fuel even though the carb was set rich.