Oxygenated race fuel

[craig bryant]

While searching for a source to buy a 5 gallon can of race fuel that I could fit in the back of the new truck, I was talking to a vendor about his supply and he asked if I use regular race fuel or oxygenated fuel. I told him that I had always used regular leaded 110 or 112 octane, usually either VP or Sunoco. He suggested that I might try oxygenated, and gave me the sales pitch as to why. Of course it didn't hurt him that it was more expensive than than the regular race fuel. I would appreciate hearing some opinions from those of you familiar with it as to whether or not it's better, worse...more powerful, etc. Again, any and all opinions and advice is greatly appreciated. Thanks.

Craig

 

[Don Walsh]

Refer to the GCR 9.3.26. It gives all the specs that must be met. I would question whether an oxegenated fuel might meet all the specs, but it might be worth investigation. As to a performance advantage, I have no idea.

 

[Dennis Shaw]

I cannot comment as to the ability to pass any fuel regulations.
Every engine I have dyno tested with oxygenated fuels have made more power. At least a 2% increase.

 

[Joel McGinley]

The chemistry is pretty obvious on this topic. David Vizard's book "Tuning BL's A-series Engine" has a great diagram: to produce 100 HP for 1 minute requires a volume of fuel about a 3 inch cube or 27 cubic inches, but the corresponding air is a 5.3 foot cube or 150 cubic feet!! The volume ratio is about 9600:1.
It is relatively easy to get enough fuel into a gas piston engine. It is the airflow, which carries the oxygen, which is difficult. The air only contains 21% oxygen, so most of what is brought in doesn't help combustion. So adding oxygen or other oxidizers to fuel can add power without requiring more airflow - probably in a big way... When drag racers run nitrous oxide, it is not as a fuel but an oxidizer- they add huge amounts of fuel to the nitro/air intake to make the extra power.
As far as I have ever read, such oxygenated fuels are strictly prohibited by SCCA - maybe to help keep us from poisoning or blowing ourselves up?? This also has caused problems with some pump(street) gas used for racing in SCCA. A few years back some FV racers got caught with oxygen-bearing additives in the engine oil, which presumably were released as the engine warmed and were sucked into the crankcase-ventilation system.... Perhaps this also led to the rulebook phrase that "permitted items may not also perform a prohibited function..." - Joel

 

[James Rogerson]

All pump gas is oxygenated. All classes can now run pump gas or any other oxygenated fuel that meets DC & percentage by volume of any and all of the named agents and those un named.

James

 

[Don Feller]

Isn't that why SCCA started testing fuel?

 

[blamkin86]

Here's my knowledge of the Oxygenated Sunoco 98, which I ran for a couple years:

1) It's extremely light sensitive. Meaning that, if you fill your jugs with it, and those jugs travel in the back of your truck for a few hours to an event, you've likely killed the fuel. When it's dead, it appears to have small spheres of a dark oil or some foreign substance suspended in it - and the blue/green/whatever color is gone to clear.

You can somewhat mitigate this problem by buying a 55 gallon drum, or carefully and dutifully covering your fuel with dark trash bags... but it literally takes 10-20 minutes in the sun to kill this fuel.

2) The 98 oxygenated makes a little more power than the 100 unleaded that's somewhat commonly available in street pumps at fancy gas stations.

To answer the question, is oxygenated fuel worth the trouble? Make a couple runs on the dyno with your 110/112/116 leaded, syphon out the tank and replace with the 98.

Just be careful not to trash the fuel on the way to the dyno - which would drastically skew your results.

 

[James Rogerson]

We have a dyno and pump 93, 98 race, 110 lead. We also have had all the new Shell unleaded fuels on site to test. All the exotics degrade quickly stored in plastic jugs. When new everything produces numbers as to be expected. Not new is worse than kerosene.

james

 

[JasonIsley99]

Why does any of this matter if the GCR/Sups require you to use the track fuel?

 

[Bobby Lentz]

this degradation issue is new to me and raises lots of questions...

Does it apply to our normal 110 leaded? What steps do people take to avoid this? Is it just sunlight that causes it? what about fuel sitting over the winter or for a couple of months between races?

insights appreciated...

 

[James Rogerson]

Why does any of this matter if the GCR/Sups require you to use the track fuel?

Because less than 10% of the driver population attends the runoffs and those Sups mean nothing to the 90% that don't have to meet that rule.

 

[JasonIsley99]

Why does any of this matter if the GCR/Sups require you to use the track fuel?

Because less than 10% of the driver population attends the runoffs and those Sups mean nothing to the 90% that don't have to meet that rule.

I thought the track fuel rule applied to all nationals.

 

[Dave Gomberg]

Isn't that why SCCA started testing fuel?

No. Both in the previous and current fuel testing regimes, the concern has been for safety. (Some prohibited substances are known carcinogens; some are highly unstable creating the risk of explosion or ignition under what could be considered ordinary conditions; etc.) The old prohibited substances list had too many holes in it and some fuel blenders were introducing very troubling compounds. The current list eliminates those.

It is the case that many of those substances introduce extra oxygen into the combustion chamber, but (as someone already pointed out) there are still permissible compounds that do that. The most obvious and common is ethanol (which is limited to 10%).

Dave

 

[Dave Gomberg]

Why does any of this matter if the GCR/Sups require you to use the track fuel?

The GCR contains no such requirement. Individual races may have such a requirement in the Supps, but this is still fairly unusual.

Dave

 

[Dave Gomberg]

this degradation issue is new to me and raises lots of questions...

Does it apply to our normal 110 leaded? What steps do people take to avoid this? Is it just sunlight that causes it? what about fuel sitting over the winter or for a couple of months between races?

insights appreciated...

Light degradation of fuel has been well known for a long time. Many race fuel manufacturers/blenders/suppliers routinely warn of this. The cases cited by Bill are extreme, but not impossible for specific compounds in particular cases. Another type of degradation is exposure to air. The usual advice is to keep jugs full and tightly closed to minimize these effects.

Dave

 

[blamkin86]

The cases cited by Bill are extreme, but not impossible for specific compounds in particular cases

Sorry, I don't think you can characterize what I said as extreme. It's quite common for "good" race gas to go bad when exposed to light.

As with any gasoline, it should be stored in opaque, tightly sealed containers and kept where temperatures are stable. Exposure to sun light (ultraviolet light) can degrade the octane of this fuel and must be avoided.

http://www.racegas.com/fuel/20

Race fuel has a very good shelf life. It is however, very sensitive to light, so it should not be stored in clear containers. Fuel can be stored for extended periods of time as long as it is in an air tight container. Race fuel jugs and Plastic drums are not good for long-term storage; if you are going to store your fuel for the winter, use a quality steel drum and keep it inside.

http://www.motorsportsracingfuels.com/FAQ.html

 

[R. J. Sorensen]

Use of Propylene Oxide at Road Atlanta Run-Offs era was one of the main reasons SCCA began fuel testing.

Klotz (Indianapolis, IN) has always advertized that if you give them your race organization's fuel rules/testing, they can formulate an oxygenated fuel to "beat" them.

I have no doubt there are some exotic fuels in use in SCCA.

RJS

 

[Dave Gomberg]

The cases cited by Bill are extreme, but not impossible for specific compounds in particular cases

Sorry, I don't think you can characterize what I said as extreme. It's quite common for "good" race gas to go bad when exposed to light.

What I meant is that you talked about things going bad in a short time. That is at the "unusual" if not extreme end of things. We're not disagreeing at all about the general issue.

Dave

 

[Dave Gomberg]

Use of Propylene Oxide at Road Atlanta Run-Offs era was one of the main reasons SCCA began fuel testing.

Klotz (Indianapolis, IN) has always advertized that if you give them your race organization's fuel rules/testing, they can formulate an oxygenated fuel to "beat" them.

I have no doubt there are some exotic fuels in use in SCCA.

RJS

Klotz is certainly one of the worst offenders, but the latest iteration of the prohibited substances list has closed the door pretty tightly. Several fuels claiming to provide an advantage have been tested since the latest update. The results have shown that either there is no real gain or, if there is, that the fuel is not SCCA compliant. (Most of that testing has been underwritten by SCCA Enterprises since spec classes are most affected by "hot" fuels.)

Now, if you mean that there may be some competitors who are using non-compliant fuel, that is possible. Only a few regions in the country have programs in place to do laboratory testing on any sort of regular basis. As has been the case throughout SCCA's history, competitors who are convinced that someone is using non-compliant parts or materials (including fuel) are expected to file a mechanical protest.

Dave

 

[blamkin86]

What I meant is that you talked about things going bad in a short time. That is at the "unusual" if not extreme end of things. We're not disagreeing at all about the general issue.

Dave

Gotcha.

My experience was with the Sunoco 98, which I think is very attainable for most people - and maybe 20 minutes was an exaggeration, but the problem happened between filling up plastic jugs in Denver, and arriving in Byers at HPR about an hour later. Yes it was very hot, maybe that was a factor as well.

I also left my cell 1/2 full over the winter, and the fuel did not go into that precipitated state. I assumed it was because the cell is opaque.

I guess I just wanted people to be aware this happens - at least to me very quickly - and if you're going to run this fuel, you're going to have to be vigilant with it.