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nicholas655

nicholas655

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i want to know if i go to a higher nitro content if its safe to do that , i currently run 15% and want to get 20 or 25 , any reccomendations?
 
You may need to shim the head but other than that you'll just have to re-tune. Going to a higher nitro % will allow the engine to run cooler. One thing you don't want to do is go from higher to lower so make sure you're not going to switch back.
 
Take the head off and there should be a copper gasket that goes in there. You may have gotten an extra with the mill, if not you can order them.
 
ok so does that mean i have to add an extra one on top of the one thats there or what i dont quit catch what you want me to do , i get that there is supposed to be a gasket ,but...
 
nicholas655 said:
ok so does that mean i have to add an extra one on top of the one thats there or what i dont quit catch what you want me to do , i get that there is supposed to be a gasket ,but...
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The shims he is referring to help determine the compression ratio of the engine. Adding shims lowers the ratio removing will raise it. Look up the specs on whatever motor you have and see what they recommend for nitro content. Chances are that upping from 15% to 20% will not require any change. 25% maybe.
I disagree with not being able to go lower, I dropped back from 20% to 16% with no problems, actually the best this engine has ever run.
 
20% fuel does not need a shim 25% is still debatable but for 30% you will need a head shim.

another factor is what size engine are you running? .12 or .21 or larger this also factors into if you need a head shim of not most .21 and larger don't need a head shim to run 30% but .12 up to .21 require a head shim to run 30%
 
I'm running the stock engine on th revo 3.3 and thanks for the good answers ,
 
The higher nitro content actually will make the mill run hotter. Traxxas recommends using their 30% fuel for break-in so the 3.3 should be okay. (Correct me if I'm wrong, guys.)
 
evilgrin said:
20% fuel does not need a shim 25% is still debatable but for 30% you will need a head shim.

another factor is what size engine are you running? .12 or .21 or larger this also factors into if you need a head shim of not most .21 and larger don't need a head shim to run 30% but .12 up to .21 require a head shim to run 30%
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That is not true, some mills will run 30% with no problem with out a additional shim.

For the 3.3, 20% is no problem, no shim needed. Heck the 33% Traxxas fuel is made for Traxxas mills, and they didnt add extra shims when I bought one. So 20-25% should be no problem.

As for fuel choices, everyone has a pick. My old 2.5 trx ran great on Trinity Monster HP 25%. I run TQ Fuel in my big blocks now.

hamz9561 said:
The higher nitro content actually will make the mill run hotter. Traxxas recommends using their 30% fuel for break-in so the 3.3 should be okay. (Correct me if I'm wrong, guys.)
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Your wrong! LOL

Hight nitro content will makr it run cooler. The oil is whet burnd hotter.

Traxxas does not say to use 30% since they only want you to run Traxxas fuel.So 20% or the 33% Traxxas fuel should be fine.
 
I'm probably going with 25% see if there is a big improvemnt compared to 15%, they also have 40 % apparently but wouldn't that be too much
 
hamz9561 said:
The higher nitro content actually will make the mill run hotter. Traxxas recommends using their 30% fuel for break-in so the 3.3 should be okay. (Correct me if I'm wrong, guys.)
Click to expand...

As psu said, the oil is what causes the engine to run hot.


Nicholas if your going to 25 you will be all set. I run traxxas 33% in my 3.3 with no problems.
 
Good GOD!!! my typing is horribile!!!! I just reread my post...........I would fix it but it would make this post pointless....except for spaming!

Do you think thats the biggest misconception in nitro RC? That higher nitro content mean it will run hotter?
 
I think people get skeered when they here that you'll have better performance but sacrifice engine life when you go to a higher percentage. I don't necessarily beleive that to be true, as a matter of fact I think it's quite the opposite.
 
Yup, its all in the tune. And the fact you will have to retune more often with higher nitro %.
 

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