race fuel advantages?

[Honda2000]

A friend gave me a stock bore 11:1 wiseco piston. We installed it today. I was wondering what the advantage of running race fuel would be, i was also wondering if i would gain any H.p by running race fuel over premium. Thanks!!

[nosliw]

higher octane fuels just allow you to run highercompressions without detonation.

the lead in the fuel will help lubricate things, though. you probably won't notice it though.

so basically, unless your doing long hill climbs all day in the desert, i don't see a reason to run anything but premium unleaded pumpgas with 11:1


oh, race gas smells better.

[GPracer2500]

"Racing fuel" is an amorphous term. There are tons of different racing fuels available. Some will add measurable HP on even a completely stock engine. Others are little more than pump gas with lead added to raise the octane rating. A common mistake is to judge a fuel based on its octane rating alone. The ONLY thing octane rating tells you about a fuel is its resistence to detonation (which is an abnormal and harmful combustion phenomenon). There are a variety of other important qualities that impact how any given fuel will perform.

So to answer your question, it all depends on which fuel you're considering using. If your engine does not detonate on pump gas, then a higher octane rating will do nothing to improve performance. But if you want to spend the money on a very high quailty racing fuel then you can realize an increase in HP, improved throttle response, consistant jetting, and overall higher performance.

Here's a quick example of three commonly available racing fuels from VP and premium pump:

Premium Pump: Not especially deto resistant but probably adaquate for many 11:1 EX builds--not always though.
VP Red: Deto resistant but offers few (if any) other advantages.
VP C12: Deto resistant plus somewhat improved performance. May or may not actually produce more HP but will rev faster and jet consistantly.
VP U4: Deto resistant in most engines plus will produce higher HP (mostly) because of it's oxygen content.

[note: The above evaluations of those fuels are not exact. My comments are generalized to illustrate how three different racing fuels can perform differently in a mildly built EX.]

[buster024]

Some will add measurable HP on even a completely stock engine

I could have sworn similiar threads about the use of race gas in stock engines said they woulnd't gain you a thing. I'm interested in running a cleaner, higher hp engine, but I run a "stock" engine with a few intake mods. If $$ wasn't the issue, does it help/hurt/hinder to run something like a vp u4?

http://www.exriders.com/vbb/showthread.php?s=&threadid=232376

[underpowered]

alright, some of what GPracer said was correct, while other stuff is a little misleading.

Race fuel will not make any more power than pump fuel on a stock motor, unless you get an oxygenated fuel, known as Oxy gas. Oxy gas has an oxygen additive that basically brring mroe oygen into the combustion chamber along with teh fuel. you will have to jet richer because of this, or it may cause a lean condition. oxy fuels do create more power due to the increase oxygen in the combustion chamber.

Most "race fuels" are better for your engine because they are more consistant than pump fuels. the octane rating on the pump is the minimum you are gettin there, someitme it varies byt a few points. howver, most quality race fuels are true to their octane ratings and run more consistantly than pump gas. also, a quality race fuel will burn cleaner than pump gas. todays pump gas is crap. with propper jetting your tail pipe should be cocoa brown, ut with pump fuell no matter what your tailpipe will almost always be black to the additives in it. with a good race fuel you can acheive the cocoa brown color signifying prerfect jetting. There are advantages to running race fuels in a stock engine, but none involve power. but also remember running too high of an octane will hurt your power.

[buster024]

Sooo....that being said, ($$ aside), with my basic intake mods, would I be losing hp's if I went to a vp u4? Or, would/could it increase the life of my motor?

[GPracer2500]

Originally posted by buster024
Sooo....that being said, ($$ aside), with my basic intake mods, would I be losing hp's if I went to a vp u4? Or, would/could it increase the life of my motor?

You wouldn't loose HP, you'd almost certainly gain HP. I don't think it would have any major impact on engine life--but only if you purge the engine and fuel system of the fuel before any period of storage. Oxygenated fuels have mildly corrosive properties. For a recreational quad I can't imagine the cost of oxy fuel would be worth it for the vast majority of people.


Regarding octane, it's not the consistancy of the octane rating that affects the consitancy of the jetting. It's the specific gravity (density) of the fuel that matters. Pump fuels and "budget" racing fuels have specific gravities that fall into a range; any given batch of fuel is likely to be a little defferent from the last. With the better racing fuels the specific gravity is specified as an exact number and should be the same each and every time. This also helps to ensure your racing fuel has not been contaminated and is the actual fuel it's suppose to be. You can measure the specfic gravity with a hydrometer to get an indication of the condition of the fuel.

[Honda2000]

i have a stock bore 11:1 piston like earlier stated. I also have a stg 2 hotcam K&N, t-4 slip on, and a rev box. Is there anything else i can do to get more power without tearing my whole motor apart? Thanks a lot!!!

[nosliw]

Originally posted by Honda2000
i have a stock bore 11:1 piston like earlier stated. I also have a stg 2 hotcam K&N, t-4 slip on, and a rev box. Is there anything else i can do to get more power without tearing my whole motor apart? Thanks a lot!!!


maybe a powerbomb header if it'll fit up to your t-4.

getting your gearing set up to your liking helps a lot.

[GPracer2500]

Nitrous! :)

[Honda2000]

I thought the Power bomb headers are designed to fit any slip on aren't they?

[Honda2000]

does anyone know for sure?