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Old 12-20-2005, 10:25 AM   #1
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Default DIFFERENCE BETWEEN NITRO PERCENTAGES?

HI I HAVE BEEN RUNNING ODONELL 30% IN MY ENGINE AND I WANTED TO KNOW WHAT IS THE DIFFERENCE BETWEEN 30%AND 25% FEULS. HOW WOULD IT EFFECT THE ENGINS PERFORMANCE AND WOULD IT WEAR OUT MY ENGINE FASTER? THANKS
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Old 12-20-2005, 11:59 AM   #2
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Basically, Nitro carries oxygen with it into the engine. The higher the nitro, the more fuel cah be burned at one time. The wierd thing is, the more fuel that you pass through an engine, the cooler it runs. Thus, higher nitro should run cooler. Lower nitro means less oxygen/fuel. Lower nitro will yeild longer run times per tank but higher temps and less power because less fuel is being burned and passed through the engine.
You may notice that higher nitro fuels have lower oil content. Part of the reason for this is that higher volumes of fuel passing through means more oil passing with it.
Why can't we run 60% nitro like the boat guys? Water cooling. Once the nitro gets that high, there is less ethanol (the other 60% of the fuel's content) that both burns and helps to cool the engine by passing through in excess.
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Old 12-20-2005, 01:28 PM   #3
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The difference is in the oil content. It's the oil that keeps your engine lubed and running. When the % of nitromethane goes up then the % of oil goes down. Race fuels use less oil than "bashing" fuel since "serious" racers tune their engines to obtain the most power which will shorten the engine life. Some high nitro fuels have a decent % of oil and some of the synthetic oils work well in the lower amounts but you pay for that in the price of the fuel.

As the old saying goes, "Pay me now or pay me later". There's no such thing as a free lunch.
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Old 12-20-2005, 01:37 PM   #4
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I know this isn't the right thread to say this in, but I'm from the ofna forums and all the threads there are for speaking your mind...

DavidKa...just outta curiousity, are you sure that's not a pancake with a bunny on it's a$$???

I'm done...
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Old 12-20-2005, 02:02 PM   #5
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The example of oil content being lower in higher nitro content fuel that I meant to bring across is that the higher nitro allowing you to pass more fuel through the engine requires the oil content to come down. If you have a given amount of 20% going through the engine and you remove 10% ethanol and replace it with 10% more nitro then you will have to richen the mixture since the nitro carries oxygen with it. If the oil content stays the same then you are now passing more oil through the engine than before with the 20%. Yould leave the oil content alone but the engine can run safely with less and it's all about performance.

possom813, it's a bunny with a pancake on it's head because the bunny is way bigger than the pancake. Otheriwse it would be like an armadillo with a road on it's A$$.
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Old 12-20-2005, 03:26 PM   #6
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That is correct in higher nitro fuels the amount of oil is the same or sometimes higher. The higher nitro percentages will have less alcohol than the lower nitro percentages. One thing to remember about nitro is it also changes the ignition point of the fuel very similar to changing the compression of the engine. Engines made for lower nitro fuels (usually higher compression) will start being more finicky when the nitro goes up. They can also start pre-detonate which is very bad for the engine. In this case you usually just shim the head to lower the compression.
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Old 12-20-2005, 03:31 PM   #7
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[QUOTE=sport10]That is correct in higher nitro fuels the amount of oil is the same or sometimes higher. QUOTE]

I think it's usually the other way around. Higher nitro fuels often have less oil. Byron's is a good example. Race 20% has 12% oil and 30% has 11%.

A colder plug usually helps with higher nitro fuel too for the reasons that sport10 wrote.
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Last edited by Davidka; 12-21-2005 at 06:30 AM.
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Old 12-20-2005, 11:17 PM   #8
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Default DIFFERENCE BETWEEN NITRO PERCENTAGES?

IM RUNNING A REX P5 TURBO WITH ODONNEL 30% FUEL AND A COLD PLUG IS THIS A GOOD COMBINATION I STILL HAVENT BROKE IT IN. Davidka IT SEEMS TO ME THAT YOU HAVE ALOT OF EXPERIENCE SO IM MOSTLY RELIING ON YOUR OPPINION. DONT FEAL BAD ANY ONE ELSE TRYING TO HELP ME I APPRECIATE THE HELP.
THANKS GUYS
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Old 12-21-2005, 06:29 AM   #9
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That is an excellent combination. What pipe will you use? The Ofna Jp2 is supposed to run very well on that engine. Plus you can bet the pipe will never break.
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Old 12-21-2005, 07:00 PM   #10
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Default difference between fuel nitro persentages?

im running a ofna 053 pipe i just got it new.
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Old 12-21-2005, 08:10 PM   #11
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Yes by the way the higer the nitro % the more abuse your engine will go with. You have to understand the more nitro the more bang you have in the engine.
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Old 12-21-2005, 10:41 PM   #12
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no thats what i used to think also but the more nitro you have the more oxygen you have which also has alot of oil. thats the right way what they wrote up on the forum is right. what you said is what i used to think too but its rreally the opposite
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Old 12-22-2005, 06:41 AM   #13
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You have to understand the higher the Nitro the higher you boost your RPMs. The higher you go the more stress you put on your motor and the more wear you get out of it. I don't know who has told you differently but they are wrong. I make and market my own fuel and have some good knowledge on this subject. The way it works in R/C and in real cars is that you can't develop power without making a sacrifice and usually the sacrifice is your engine.
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