Fuel Facts: What Is Race Gas?

Each fuel company can have its own definition of “race gas,” notes Zachary Santner, technical specialist for Sunoco Race Fuels. For Sunoco, products with an octane rating of 95 and higher fall under its Race Fuels banner. The brand currently offers some 20 different blends.

What Works for Your Car?

Perhaps it’s most helpful to think of race fuels as boutique formulas for specific needs. For example, some are heavily oxygenated, making them a good fit for turbocharged and supercharged engines. Others don’t contain any oxygen at all, like those recommended for vintage cars with long storage intervals.

Another choice: leaded or unleaded? For cars that can digest the stuff, some racing formulas contain lead since it’s an easy, inexpensive way to add octane. Of course, totally lead-free options are available to keep modern electrical components happy.

Street Fuels, Too?

Products sold as race gas are not always limited to track use. Sunoco Race Fuels, for example, offers products specifically aimed at street cars. Their 1 00-octane 260 GT is a stable, street-legal blend designed for high-performance engines. (For those who have to meet California’s fuel regulations, Sunoco also offers the similar SS 100.)

What about cars that don’t like alcohol in their diet, including many classics? Sunoco 260 GTX can fill that need, but legally it can’t be sold for street use.

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wspohn
wspohn Dork
10/6/18 1:10 p.m.

Most common mistake I see people making is believing that race gas will automatically do their street car some good.

In an old style mechanical distributor set up, zero advantage unless the timing is advanced.

In a 'search forward' programmed ECM car, which advances until it hears ping and then holds at that edge, you will get an advantage. 

Unless you advance your old style engine manually (I reccomend installing a knock sensor so you can tell when you've gone too far rather than taking the hint when the pistons come out the side of the block) the super premium race gas actually has less energy per pound than regular.

ETOH containing fuels are a whole different discussion.

200mph
200mph New Reader
10/14/18 6:44 p.m.

Race gas doesn't make power by itself.  It allows the engine builder and tuner to build in more compression and/or use more timing advance so the engine can make more power without detonation (knock).

Some modern ECU's can advance the timing to just before the point of knocking... those cars can also benefit from unleaded race fuel.  Best bet: ask your engine builder or engine parts supplier what octane to use and what jetting to run for your application.

One exception:

We provide Sunoco Race Fuels to museums and collections for use in cars that are rarely started or driven.  The shelf life of these fuels is 2+ years, where regular street gas laced with ethanol (E10) starts to break down in less than 60 days.

Our rule of thumb:

Everything we own that has a carburetor gets nothing but zero-ethanol gas.  Where to buy? Check http://pure-gas.org

 

 

 

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