tell me some more information about your Vmax6 engine. How old? About how many flights you have on it? Washers under the head ? I Have a Vmax6 engine it hauls even my heaviest fuselage(bell 222) really great. As the engine wears out, youll begin to see a gradual power loss and more overheating. You may want to consider a new piston and sleeve. Heres the breakdown of the life of one of my Vmax6 engines: I break it in with about four washers and 15% fuel. If its not producing the power I like after break in, I remove 1 washer. That will usually do the trick. As the engine wears, i'll remove washers until Im down to one under the glow plug. Then, Ill bump up to a higher nitro fuel either 20 or 25% and go back to two- three washers. When Im back down to one washer and have used none in the Vmax 6, That engine is worn out. I fly four to five gallons of fuel a year easy. Ive worn my engine out so bad that you can see slop between the piston and the cylinder wall. I just recently went with the Vmax7 earlier this year but was having some problems with it so, i really didnt start flying with it until this month. Its alot more power and it really hauls. Im about at a half gallon of fuel through it in about three weeks. I fly it on average once or twice a day. I broke it in with about 5-7 washers under the head. I say about because Im using an adapter that is about five washers thick and I have two regular copper washers under the head. So far its been great. There was a problem with Con rod breaking but seemingly this engine is A-OK. My big grin is back
. Spiro, mabey your Vmax6 is getting tired and is time for either a new piston and cylinder or mabey a whole new engine. The upgrade is kinda pricey at $90 bucks. Well, with the upgrade you do get the new engine, throttle muffler, clutch shoes, clutch bell, and starter cone. Oh yes, and glow plug and heat sink. Thinking about all that you get, its really not that bad. The Vmax7 uses the same clutch bell and can use the same clutch shoes if the hole is bored out larger and correctly. Im doing an electric version and if you decide to go electric, you will see its going to be much heavier than the gas models. Also Im hearing electric guys are having their woes just like the gas guys. Some are experiencing glitches, ESC troubles, Battery woes etc... The difference basically between electric and gas is the clean up. Id like to get my electric going soon but Im waiting on an ESC then Im ready. Oh yes and a gyro. I have two Vmax6 engines, one is a good one (still lots of power) and the other is worn out. I squeezed every drop out of it. I dont plan on getting rid of them because if my V7 ever dies, I have a back up. I need to be ordering a new piston and sleeve for the one. Ive had the heli die in flight once at about 15' off the ground and suffered very minor damage . If it was an electric, it would be like a brick falling out the sky. I hope this helps.