Sponsored article presented by Sunoco Race Fuels.
History: Lead is an inexpensive, easy way to add octane to gasoline–and that octane prevents knock and pre-ignition. In 1973, though, the EPA demanded that lead be phased out of street fuels. The reason was simple: Lea…
I collect vintage motorcycles, some of which have high compression ratios, others which do not but definitely run better on fuels more closely resembling their diet when new than what comes out of the premium pump today. These machines are mostly British, and include BSA, Triumph, Norton, Matchless, Velocette, Sunbeam and some old BMWs and Harleys as well.
For many years, I've used VP 110, which is just one of many blends offered by VP Racing Fuels. VP110 is 110-octane leaded fuel (they have unleaded as well, in various octane ratings), characteristically pinkish in colour and even smells like gasoline used to smell!
Long ago, I experimented with the appropriate mix ratio, as I knew I did not need 110 octane, and at around $15 a gallon (available in blue 5-gallon drums), it was pretty pricey to fill even a two- or three-gallon tank.
After trial and error, I found that 25% VP110, mixed with 75% pump premium gave me the most benefit and efficacy in the vintage machines. Higher proportion of race fuel and the differences are minimal, if noticeable at all. Less, and you're not getting the full benefit.
I have several blue cans in my shed. One is the newest can of VP110, one is pump premium (and clearly marked as such) and one is labeled "Mix." I don't premix a lot ahead of time; no need to do so unless you're riding very frequently.
The difference in how the bikes run is amazing. They start easier. Their throttle response is almost instantaneous—clearly superior to running on straight corn meal. And they can pull long uphills under load on hot days without knocking and pinging. Torque is improved. They also run cooler. In summary, they are happier machines and more fun and rewarding to ride.
How this translates to older cars that are sensitive to their fuel mix, I'm not sure.
Oh, one last thing. When you buy such leaded fuels from a speed shop, you need to sign a waiver that the vehicle won't be operated on public roads. Some ask what competition event you're planning on attending, place and date. I'm not advocating that anyone who might consider operating said vehicle on the road misrepresent anything here, or makes up a fictional offroad event, with a random date and place, sponsored by a fictional organizing body.
Keep the shiny side up!
You'll need to log in to post.
