I have read things about newer fuels running leaner for different reasons. It made me wonder. Are people running pump gas, or racing fuel?

Generally, we're running a mix of pump gas and track fuel (100 unleaded) to bring the octane up to to a safer level due to the higher levels of alcohol now being blended into the gasoline. Most important thing to stay on top of is the fuel pressure as pump deterioration resulting in inadequate fuel flow can cause engine failures due to excessively lean fuel mixture. Running a fuel pressure meter is the least expensive way to stay on top of the situation; an air/fuel ratio sensor is a more accurate, but expensive, alternative. See threads on this forum (or SCCA Enterprise) on the correct fuel pump test procedure.

I found a service station near which sells non-alcohol unleaded gas. 92 octane. A month ago it was $4.67 a gallon. We ran this gas straight and for one race we ran it plus added 2 gallons 100 race gas for a mix. I think the gas is for marine outboard motors just not sure.

At the COTA race I was using 93 unleaded from a Shell station about 30 miles from Austin - I assume it had ethanol. The car ran fine on the test day and friday practice. On the last 2 laps of Saturdays race the car stumbled bad at the slow left hand hairpins about 4 times - I had 1.25 gallons left after the race and very good fuel pressure so it wasn't starving.

I then mixed 100 octane race gas 40% with local gas (don't know where my brother got it). In Sunday's race about 2/3 through the car stumbled once for a few seconds again in a slow hairpin.

I have never had vapor lock before so I assume it was due to the local winter blend fuel.

A good source for non alcohol fuel is your local hot rod association. Do a Google for your local chapter. They often have a list of gas stations around town that sell non-oxygenated fuels for their old V8. I have been using non-oxygenated fuel for the last 13 years and have not replaced a fuel cell yet. That being said it might be time to replace the fuel cell after 13 years as a precaution

Martinracing98 wrote:I have read things about newer fuels running leaner for different reasons. It made me wonder. Are people running pump gas, or racing fuel?

Hey Todd, we were told to run ethanol free premium unleaded in the SRF. There is suppose to be a station North of I-270 on Route 3 in Hartford near the Lewis & Clark memorial that sells this. I plan to search it out next week to fill up my fuel jugs.

Check out: http://pure-gas.org/
I get mine from a local gas station about 3 miles from my place, 92 octane non-ethanol for just under $5/gallon.

Edit: they have a Droid and iPhone app now as well for when you are on the road.

Todd Butler