Nitromethane mixture in lawnmower fuel
Liam, Mon Jul 10 2006, 03:31PMI have a two cycle lawnmower and I am interested in causing it to run faster for novelty purposes. I would very much like not to destroy it, however if I must, I will. I was wondering if anyone had any experience with running lawnmowers from alternative fuels, especially a mix of the normal two cycle oil/gas mixture plus small amounts (<20%) of nitromethane. I am especially interested in modifications to the carburetor to allow for this.
I've seen the propane powered lawnmower, but that will surely destroy the engine after a short time due to lack of lubrication to a two cycle motor but the main reason I don't want to do this is that I don't think there were any real gains in power. I'd really only like to do this once. Any suggestions?
Re: Nitromethane mixture in lawnmower fuel
ReddyK, Mon Jul 10 2006, 05:08PM
Liam,
nitromethane is a great fuel for more power however, to get the greatest power improvements from the fuel change the compression ratio of the engine must be increased. Many engines can just have the cylinder head milled down. Some engines have blindcylinders where the head is cast into the cylinder and not removeable, these require a piston change to raise the compression. As far as the carberator it should be adjustable for the fuel change and other minor power improvements such as two stage reeds.
There is nothing like the power and noise from nitro. Its $40 a gallon price will slow most down from experimenting with it.
Hope this helps,
Steve
ReddyK, Mon Jul 10 2006, 05:08PM
Liam,
nitromethane is a great fuel for more power however, to get the greatest power improvements from the fuel change the compression ratio of the engine must be increased. Many engines can just have the cylinder head milled down. Some engines have blindcylinders where the head is cast into the cylinder and not removeable, these require a piston change to raise the compression. As far as the carberator it should be adjustable for the fuel change and other minor power improvements such as two stage reeds.
There is nothing like the power and noise from nitro. Its $40 a gallon price will slow most down from experimenting with it.
Hope this helps,
Steve
Re: Nitromethane mixture in lawnmower fuel
..., Mon Jul 10 2006, 08:06PM
you are getting ripped of if you are paying $40/gal for 20% nitro
It is like $15 at the hobby store here...
I think you may run into problems with the compression, but you should be able to get at least a little more out of it... Any thought of trying to add N2O to it
A little fogger jet in the head should work pretty well...
Keep in mind that most lawnmower engnes have an internal governer that you will have to remove.
In any case, have fun and don't blow yourself up
..., Mon Jul 10 2006, 08:06PM
you are getting ripped of if you are paying $40/gal for 20% nitro
It is like $15 at the hobby store here...I think you may run into problems with the compression, but you should be able to get at least a little more out of it... Any thought of trying to add N2O to it
A little fogger jet in the head should work pretty well...Keep in mind that most lawnmower engnes have an internal governer that you will have to remove.
In any case, have fun and don't blow yourself up
Re: Nitromethane mixture in lawnmower fuel
ReddyK, Mon Jul 10 2006, 10:13PM
The $40 a gallon was for 98% nitromethane. As strait as it comes and still be stable.
Enlarging the ports and openings would make the most difference however, it also makes for more difficult tuning. Replacing the carburator with one off of a larger engine helps the power and ease of tuning. Smoky Yunick was the two-stroke master in his early years. His power secrets book has alot of two-stroke tips.
Steve
ReddyK, Mon Jul 10 2006, 10:13PM
The $40 a gallon was for 98% nitromethane. As strait as it comes and still be stable.
Enlarging the ports and openings would make the most difference however, it also makes for more difficult tuning. Replacing the carburator with one off of a larger engine helps the power and ease of tuning. Smoky Yunick was the two-stroke master in his early years. His power secrets book has alot of two-stroke tips.
Steve
Print this page