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- Jun 30, 2012
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If you fitted six carburettors to one cylinder of your Norton commando you would cool six times as much charge as long as you got the air flow. Because you use only one main jet and the mixture has to be of a certain ratio to suit the combustion conditions, you only get a certain amount of cooling effect from the latent heat of vaporisation of the fuel. A mixture of 60% methanol and 40% hydrocarbon will give you almost the same reduction in temperature in the inlet tract. However the entrained hydrocarbon is a much better source of energy than the methanol it replaces. So in a moderately high compression engine a methanol/hydrocarbon blend is better than pure methanol as a power source. The limiting factor then becomes the compression ratio at which detonation occurs because the hydrocarbon component lowers the octane rating. I believe that BP JA would be OK with comp. ratios up to 13 to one.
I suggest a motor on 13 to one using a blend would give as good power as one on 15 to one using pure methanol, and certainly give better fuel usage rate. It is cheaper to use but takes much more buggering about to control it. I used the methanol/benzene blends many years ago however I was always scared of the benzene - causes leukaemia. Toluene doesn't do that.
If you think about a Commando motor on methanol at 14 to one comp., compared with one on methanol at 10 to one comp. - if you set them both up right, the differences in performance are almost negligible. The jetting and timings are very different. The differences in the running and engine mod. costs are very significant.
The thing I didn't mention about the Maserati blends is that they also used to use Oil of Mirbane - nitrobenzene. That's a different game again. Do they do fuel checks at the road races in your country ?
I suggest a motor on 13 to one using a blend would give as good power as one on 15 to one using pure methanol, and certainly give better fuel usage rate. It is cheaper to use but takes much more buggering about to control it. I used the methanol/benzene blends many years ago however I was always scared of the benzene - causes leukaemia. Toluene doesn't do that.
If you think about a Commando motor on methanol at 14 to one comp., compared with one on methanol at 10 to one comp. - if you set them both up right, the differences in performance are almost negligible. The jetting and timings are very different. The differences in the running and engine mod. costs are very significant.
The thing I didn't mention about the Maserati blends is that they also used to use Oil of Mirbane - nitrobenzene. That's a different game again. Do they do fuel checks at the road races in your country ?
