Nitro Troubles

[Crofter]

xhaust pressurised fuel tank

It is done all the time on the model aircraft with the same fuel, Methanol and 10 to 25% nitro. I have not heard of problems with it.

 

[timberwolf]

It could be done, tends not to move through small openings and long tubes. or put a flame/flashback arrestor in line, preasure regulating valve, and plug the tank vent. But don't a lot of races say no pressurized tanks?

Anyway the fuel in the tank and vapour would be above flammable limits (too rich to catch unless it was cold)

But I can think of better ways, like using an electric fuel pump run off the generator for a handlebar heater or small 12v bat.

 

[Crofter]

When you can burn more than twice the fuel in the same volume of air and then cram 50% more volume in with the tuned pipe it sure makes an impressive performance. http://www.arboristsite.com/attachment.php?attachmentid=22633&d=1112830140

A piped alcohol saw sure makes a stock saw look sick.

 

[stihltech]

alky

Having ran my hotsaw both ways, there is more to it than that. Right now it is back on gasoline, and I there is not much difference. Actually, a little more power now.
Someting tells me there are internal mods and fuel system mods to go with the pipe.

 

[ccicora]

I like what I was told today.... Just because you can mix a fuel doesn't mean you know how to jet or run the fuel.

 

[timberwolf]

Pipe will need to be different, the exhaust is a higher density, and it is also cooler. so all the pipe timing goes out a good bit. Also with the extra torque cone angles can be altered to take advantage of the new power curve.

 

[timberwolf]

Worked out some info on increased jet diamiters for nito, just in case anyone searched the tread and was looking for info on nitro.

Beyond opening the jets up for alky, jets need to opened on average by about 1% diamiter for every 1% of nitro. Though this ranges from about 1.2% per each % point of nitro for up to 20% nitro then 1.1% to 40% nitro, 1% to 60% nitro .9% to 80 % nitro and .8% to 100% insanity (nitro).

To take a .040 jet on gas and open it to methanol and 15% nitro I am first multiplying diamiter 1.40 to make up for the ideal fuel air ratio change from ~14:1 to ~6:1, then by 1.25 to make up for methanol wanting a richer mixture compaired to gas more like 4.5:1 in the real world in order to make max power, then mulitplied by 1.2 x 15 for 15% nitro = 1.18.

.040 x 1.4 x 1.25 x 1.18 = .083

Also need to look at oil, if you go from 50:1 (2%) to 10:1 ~10% you also need to up the jet size almost another 8%.

Beware, nitro is just legalized crack for racers and engine builders.