Its not a bike, but just imagine if it was a car.....

[AnotherRedHead]

For people that say fuel doesnt make that big of a difference, heres some solid proof. This is the best pass on C16, vs. the best pass on ULT4. SAE correction factor so theres no funny stuff....

http://img397.imageshack.us/img397/6269/c16vsult4kv6.png

I imagine in a car where HP is above 400 already, the gains would be really significant over pump gas. I mean, at 400 horses, with 6 % gain your talking 24rwhp more just by changing the fuel. I gained 8.5% if I calculated right....Imagine that.

How come no one runs this stuff in your car? Besides the price of course....


Nick

[turbostang]

I tend to look for the obvious....

So, if a simple change in fuel netted those results - I'd tend to believe the first fuel was inadequate OR the tuneup was too far off.

This is probably true more often than not.

[grape]

if it liked ult 4 it didn't need as much octane as C16...........pump gas would probably get you within 5 of ult 4. for the love of god the burn is so slow on 117 octane c16 what do you expect with street freindly compression?

nobody runs ult 4 in anything where the valve job needs to last longer than 6 months..........i've told you guys, that shit eats everything when it sits, especially valve seats.

[franks]

if it liked ult 4 it didn't need as much octane as C16...........pump gas would probably get you within 5 of ult 4. for the love of god the burn is so slow on 117 octane c16 what do you expect with street freindly compression?

nobody runs ult 4 in anything where the valve job needs to last longer than 6 months..........i've told you guys, that shit eats everything when it sits, especially valve seats.
im going to back this statement after seeing the valve from the briggs engine tonight that had been running the vp

[Cmarsh93z]

VP Racing Fuels, Inc. announced some bad news for powersports enthusiasts today – it’s discontinuing U4, its most popular racing fuel in the powersports market. The good news? VP came up with something even better – U4.1.

“U4.1 is an updated version of VP’s U4 racing fuel, with improvements in several significant areas,” said Steve Burns, VP’s President and CEO. “Compared to U4, U4.1 offers up to 2% more power, translating to as much as 8% more power than premium pump gas, as well as no sticky residue and a less pungent aroma – all for a lower cost. This is a major technological step, considering that since its introduction in early 2004, U4 had become perhaps the most successful racing fuel in the powersports market and VP’s fourth best selling fuel overall.”

“For its time, U4 was the most technologically advanced fuel on the market for its targeted applications,” Burns continued, “but there are always improvements that can be made. At the time of U4’s introduction, the engineering trade-off was a significant gain in horsepower while accepting its propensity to accumulate a gummy residue during storage, requiring fuel tanks to be drained between uses. For competitors, this was a small inconvenience in return for 6% more power than premium pump gas at an economical price.”

“The development of U4.1 – a fuel with all the upsides of U4 and none of its downsides – is a real breakthrough and just the latest example of VP’s technological leadership,” Burns added. “Although not a high octane fuel, U4.1 runs in engines with 10:1 to 12:1 compression with excellent resistance to detonation. Technologically speaking, this is the best fuel we have ever produced.”

Like U4, U4.1 is designed for all 4-stroke applications as well as stock 2-strokes. Oxygenated with ethanol, U4.1 is legal for off road use throughout the U.S. Although U4.1 is illegal for AMA Pro Racing due to its oxygen content, it’s still legal for AMA amateur, CCS, WERA, AFM and club level racing. It will retail for $9-11 per gallon, depending on the size of container ordered.

Use of U4.1 will yield faster and more responsive engines without harming carburetors, O-rings or gaskets like some other race fuels will. According to Burns, its power gains compare to VP’s best AMA Pro level race fuels for less than half the cost – a comparatively easy, inexpensive way to generate additional power. For example, a new exhaust system wouldn’t generate as big a power increase and the increase would be on a smaller slice of RPM range, while U4.1 produces power gains at all RPM levels.

NicK
DFW Powersports