RC Car Mags

vectra wrote:

....I have read plenty of posts on several forums about 25% nitro and I have yet to hear anyone saying anything like " My engine died a sudden death after using 25%"........

Let's forget about "reading posts" about 25% fuel for a minute.
I have USED EVERY NITRO % UP TO AND INCLUDING 65% NITRO FUEL.
So what did I learn from doing this?

Nitro is not necessary. The propellent is methanol, and the air has cost free oxygen in it which , burns your methanol just nice. Nitro is like extra air to the engine, and extra cost to the modeller.

Nitro adds torque. Not speed.

If an uphill struggle ensues, which reduces top speed, THEN the extra torque will raise top speed.

Torque from nitro makes the car accellerate faster, as if it is tuned leaner than it actually is.

So when you lean it out (to raise temp, raise compression, raise torque) you reduce the fuel intake, which unfortunately also reduces the oil intake since the oil is in the fuel). Then you have higher temps but lower oil.
BUT if you add more nitro to the fuel instead, you are adding oxygen, and you get the torque without leaning it out. The oil goes in with the nitro. The engine still gets lubricated.

When you put a little nitro in you get a big improvement in performance. But as you put more nitro in, you get better performance, but not so much improvement. The added nitro produces less benefit than before. By the time you get to 30% nitro, you almost have to double your nitro to get better performance. That is why we go from 25 - 35 - 65 % nitro. The in between levels are not distinguishable and worth the trouble.

The guys who use high nitro with the same oil and settings that they used with low nitro break their conrods, and wear out their piston liners, losing compression, until their engine will not start unless it has high nitro available.

The high nitro needs more coolant to save the engine from wear. So the oil should go up as the nitro goes up. OR you use the same oil, but at a richer setting when the nitro goes up. Eg use 5% nitro with 15% oil. Use 10% nitro with 18% oil Use 35% nitro with 20-24% oil and two types of oil is better than one.

In oils: castor tolerates abusive high temps (caused by high nitro) better than synthetic oil, but synthetic is the better oil at the correct temps.

Yes - nitro helps win races.

Yes - high nitro reduces engine life.

You need cooler glowplugs with high nitro.

A carburettor with a bigger air intake produces more power by getting athmospheric oxygen in with the fuel, without having to pay for high nitro fuel. BUT this carb is more sensitive to tuning, and the beginner may not get his engine going right with it. So the nitro helps someone with a budget enginewho can't tune the best, to get more power with less hassle, than using a performance engine.

Regarding the hobbyshop guy and his advice: the beginner with high nitro eg 16% compared to the beginer with low nitro eg 5% .... the high nitro beginner will break about 80 euro worth of parts extra over the other beginner in the first 6-10 months. this averages out over extra glowplugs, sometimes a piston & liner, and seizures which necessitate expert help. As ability goes up, the breakages attributable to the higher nitro go down.

Of course the expert who also uses high nitro in the performance engine has a big advantage.

A good tuned pipe is about equal to 5% nitro power advantage, but only while operating within the rpm range of the pipe's tuning.

Hope this helps dispel some of the myths.

coolwings wrote:

..... high nitro reduces engine life.....

Plug wrote:

I was right then vectra;)

Theoretically:
If you put more nitro in - now you've got higher temps & more power - next you richen the carb to get lower temps again - the accellerated wear should be minimal. But you should still have a snappier performance than before.
Only thing is ... nobody does that.
We all run it hotter power at a hotter temp. So our only saving is to also have higher lube from extra oil.

Cos in the real world - It's more more like ...... YEEEEE HAAAAAH ! !

Flunked wrote:

I forget what this topic is about, Ooops!

Uh... Uh..... We've done it again .......

We need a thread called : whatever you're having yourself

Plug wrote:

Anyone know if its posible to blow up a nitro engine I'd love to try it with my old engine:D

Thanks a lot !
Now I have got this idea involving old engine cases, home made gunpowder, nitro-string fuses, and smoky flash-bang-wallop explosions spinning round my imagination

Plug wrote:

LOL:D I need to know where to get the ingrediants for gunpowder, I know what they are but getting them would be a bit of a problem:(

Remember the newspaper news report we saw about the american guy who was making rocket fuel, and blew both himself and his house up early this year.

Thinks : Not a good role model to follow