NewDuc,
I am with you, use only as much octane as needed to pervent knock, the rest cost you power.
From
www.vpracingfuels.com/vp_01_fuels.html
U4TM
Used in stock and modified 4-stroke applications, as well as stock 2-strokes. Makes up to 6% more power than pump gas and any basic nonoxygenated racing fuel. Passes fuel rules for AMA amateur racing, and is also perfect for club level racing, CCS, WERA and AFM.
• Color: Clear
• Oxygenated: Yes
• Motor Octane: 92
• Specific Gravity: .718 at 60° F
NEW! U4.2TM
The latest generation of our U4 based fuels, this fuel is a direct pour-in replacement for U4 with little to no jetting changes required - +2 main jets and +2 pilot jets at the most. Makes power equivalent to U4 with no sticky residue and a less pungent odor. U4.2 passes AMA amateur fuel rules and is perfect for club level racing, CCS, WERA and AFM. U4.2 makes up to 6% more power than pump gas.
• Color: Blue
• Oxygenated: Yes
• Motor Octane: 102
• Specific Gravity: .784 at 60° F
U4e
Developed for those states that restrict the use of MTBE in fuels. Will work well in the same applications as U4, with comparable power increases.
• Color: Pink
• Oxygenated: Yes
• Motor Octane: 93
• Specific Gravity: .718 at 60° F