hot run

[savage]

What is it? The higher the nitro percent is the cooler your engine will run or the higher percent the hotter it runs.







Now my 21bb has had problems since I got it. I get it tuned, than when I start it up I need to tune it again. Now the all the needles are messed up even the mid range. Should I turn them to what the manual says.


also what engine is better the xtm 24.7 or the picco 26. Or the truckzill kit. By the way I have only ran my savage for 4 months and had it for a year, because of this.


Or does the 21bb always run like crap.

 

[mcvickj]

What kind of problems are you having? It is always suggested to start with factory settings and tune from there. Do not adjust the mid range needle. The only three screws you should be adjusting are the Idle Speed Screw (ISS), the Low Speed Needle (LSN)( and the High Speed Needle (HSN). Adjusting the midrange needle will cause you nothing but headaches.

 

[savage]

The problems I'm having are engine tuning. I still do not know what the needles should be. I do not know why I have to tune it. So now that I turned the mid range needle I need to buy a new engine.

 

[tbsleeper]

no find out the original setting set them all back, then re tune and do not tune teh midrange

 

[Maxx Trooper]

Originally posted by savage
What is it? The higher the nitro percent is the cooler your engine will run or the higher percent the hotter it runs.

the higher the nitro % the hotter the engine will run. i think most guys run 20% in there nitros, some 10%, but a few guys fun the 30%. the higher the nitro % the lower the oil %.

later

 

[savage]

I have been using 25% and the manual says 20%, so would that make the engine temp go up about 10, 20 degrees. Would I have the engine running good if the mid range at 3 1/4 like factory.

 

[SkyMaxx]

Hmmm...I've always been told that a higher nitro content makes a cooler engine. I could be wrong, but I believe higher nitro equals cooler engine.

 

[robriguez]

I would agree with the higher the nitro % the cooler you would run. My uneducated guessing would leed me to believe that because of the higher nitro % you dont have to lean the mixture out so much to get the same power. If you are running richer then you will have more lubrication, more lubrication would mean that the parts arent rubbing so much, less rubbing = less heat buildup = lower temps with same performance.

 

[DOGPILE]

threadlock the midrange at 3 1/4 turns, its a bad idea having it there in the first place. Dont bother trying to tune until the engine is hot, i have been running tornado 25% since break in and had no trouble starting or running, needles have been set slightly richer because of the lower oil content in the 25% fuel and i have never needed to retune yet. Engine will run hotter because there is less lubricant in the fuel but not too hot as too cause damage.

 

[Maxx Trooper]

But there is less lubrication in the fuel so wouldnt that cause u to richin the carb settings? i dont know, maby I'm confused...

later

 

[F1 Junkie]

The more nitro the more fuel is needed. Nitro is just an oxidiser (methanol is what burns to give up its energy) and the higher the content of nitro in the fuel the less there is of methanol which makes it necessary to richen the mixture. The richer the mixture the cooler the engine. People burn up engines by running high nitro fuel without retuning their engines (which also means head shim adjustments) and then blame the high nitro fuel.
There isn't necessarily less oil in the fuel. 18% oil is 18% oil regardless of the nitro content. I don't know for sure but some fuel manufacturers may reduce the oil content in order to increase the methanol content. Hmmm, another reason for more heat / shorter engine life.
Sorry for ramblin

 

[SkyMaxx]

Nicely said, F1 Junkie.