Nitro % and Temp?

I didn't convert you celcius temps to farenheit, but anything over 260° or 270°f is too hot. With more nitro % you need to richen the hsn by as much as 3/4 turn depending on the conditions.

If you really want a cool running powerhouse you should try some fuel with about 11% or 12% oil content, if you haven't already.

Lets start with what kind of fuel are you currently running? Hopefully not Traxxas!! That would be 1/2 your problem from the get go!!!

Traxxas fuel is fine in traxxas engines. It's a bit messy in higher end engines because of the oil content. In my experience, traxxas engines run best with traxxas fuel. Sounds to me as if it's tuned just a hair lean.

The first time I put O'donnell in my 3.3 it was like a night and day difference from traxxas fuel. That's only a 2% difference in oil. Now I use byron's 20% and 30% mixed 50/50. I don't have any traxxas engines these days, but the 4.5% decrease in oil is incredible! It's 11.5 now and all abc engines are still very safe with that.

Most of the engines I've dealt with had some amount of wear, mostly from air leaks causing a lean condition. Maybe the extra oil aided in compression!

LOL that could be! Hey man it's good to see you around again.

Hell yeah bro. It's good to be back.

I'm back on four 10 hour days now til april, feels good!

I'm running "AT RACING" fuel. 20% nitro, 10% synthetic oil and 5% Castor.

Can't beat 4 10's. Sorry about the thread jacking bro. Let us know if your able to tune er in. If not, we'll go from there.

so i retuned today. its a bit hot today 80 degrees f which doesn't help. i have the motor running at 226F after a WOT pass and maintains that after idle. iv gone about a full turn rich on HSN running 1/2 to full turn rich on LSN and its running ok. but pretty slack.

i also have an oil leak coming from the bottom of the manifold which I'm pretty sure its cuz i bent the exhaust i tad (squashed it towards the motor somehow). got a new one on order.

also just took it out again, its just drizzling atm so i thought it was a great opportunity to take it for a run while its cool. i leaned the HSN out a bit and put my gps on it. got 40mph from a car that gets 45 out of the box. figure thats pretty decent. anything i could do to make this run 100%. are there any radiator setups that would be cost affective and work in these hot conditions or is it just running like a hot B*&^H for another reason?

That leak will make the tune real erratic. Air leaks are the enemy. I seal every engine before running them just so I know it's sealed.

The Traxxas 3.3 runs a bit hotter than most other nitro engines. Mine ran best around 260-270° F. It was still running strong after about 4 gallons when I replaced it with a big block.

Yeah good luck getting a true 45 out of it in stock form. Traxxas overstates their speeds just a hair, kinda like hp ratings from most manufacturers.

yeh mine was running awesome at 270f, but i was told that thats possibly y my clutch bell bearings are destroying them selves after about 2-3 runs.

thoughts?

No, that woudn't cause bearing failure. The bell must be shimmed correctly. It should have just a "tick" of play when cool. This allows room for the metal to expand when it heats up. 270 is fine for traxxas engines. Normal really.

hey all, well i shimmed up the clutch bell. the rubber/nylon shim that came with it 0.5mm must have given somehow and deformed itself so i ripped that out and put in some metal ones. noticed when i went to take it for a run this avo that my exhaust was broken (also bent as i noticed a few weeks ago). thought it was where the oil was coming from and i was right. so i went out and got a new one of those as well.

took it for a run this avo (was a bit cooler too) and was running really well. got it richened out on the LSN a little to help cool it down while idling and tad rich on HSN but its only hitting around 105-115 degrees C (220 - 240F) which is pretty decent. ill have to give it a run tomorrow when the suns pounding and see how it goes....