Tuning Your Fuel to Your Application
Minazzi, uses coulemetric...
Minazzi, uses coulemetric titration to detect the presence of water in solution, an important test particularly for oxygenates introduced to fuel blends.
OK, so it’s obvious that spending a few extra bucks for race fuel instead of filling your fuel jugs at the local Gas-N-Go can be beneficial both in terms of horsepower, tuneability, detonation protection, and even throttle response. But then there’s the other end of the spectrum. If you take a look at the available offerings for circle track racers just on the VP Racing Fuels website, the number of options available can quickly become a bit intimidating. And that’s not even counting all the other racing fuel manufacturers out there.
But that’s OK because Burns says that’s what the tech department is there for. Freddie Turza is the R&D Director at VP and says he also spends a lot of time helping racers not only find the perfect fuel blend for their needs but also tune their engines to make the most of that fuel.
“The reason we have all these different fuel blends is because different engine packages may require different things,” Turza explains. “For example, let’s stick with the crate motor racers. I’ve had this happen several times where a crate racer will run the track fuel. It’s usually either a 110-octane race fuel or our C12 which is 112-octane and one of our bedrock racing fuels. C12 is a great fuel for a lot of different applications, but it isn’t designed to suit the needs of crate racers.
This is VP’s testing lab used...
This is VP’s testing lab used to determine the octane ratings for its fuels. Most fuels are rated for both a “Motor Octane Racing” and a “Research Octane Rating.” Racers should always check for the Motor Octane because the testing for that rating mostly closely relates to the stresses a racing engine places on the fuel it burns.
“So the crate guy will come up to me and say that he runs better with pump gas than the track fuel. And the fact is that the track fuel may be a little too high grade for his needs. The fuel is designed for a high-compression, high rpm motor, and burns just a little too slow for the needs of that crate.
“But when I can turn him on to a fuel designed for his motor like the CHP, then it really becomes obvious to him that the pump gas really isn’t the best option either. The CHP is blended specifically for the crate motor, and the octane and vaporization rate is dialed in to work with it.
“With the Chevy 602 crate motor I’ve seen gains as much as 23 lb-ft of torque and 25 horsepower. By switching to CHP the average guy will see 16 to 18 horsepower and 12 to 15 lb-ft of torque. And with those limited horsepower crate motors that kind of gain is quite an improvement.
“The key,” Turza continues, “is getting the engine tuned to work as well as possible with the fuel. Then, because the fuel is so stable you don’t have to worry, the performance will be the same night after night. Usually, we will start with a major jet change when switching to CHP for the first time. With a 600 Holley carb we will increase the jets about six sizes all the way around. Then we will make some power pulls on the dyno until we achieve maximum torque and horsepower. We’ll just keep putting fuel to it until the power plateaus off.
VP provides trackside fuel...
VP provides trackside fuel service for nearly 200 race events of various types each year. If your track only carries one type of fuel and it’sn’t the fuel you need, VP can ship you fuel in barrels that is guaranteed consistent from one batch to the next.
“Now we know the engine is making good power, so it’s time to put it in the car and see what it has got and tune for driveability. On the track we are looking to tune the engine to give the driver the best throttle response possible so that he can really drive the thing. That may require a little work with the squirter or the low speed settings on the carburetor.”
Interestingly, Turza says that much of his work with racers and teams isn’t talking specifically about different fuels, but rather on engine tuning. “Because of the growing popularity of the crate classes,” he says, “many of these racers have alienated themselves from the engine builders. Engine builders have always been the resource when it comes to helping racers maintain and tune their engines and carburetors. But engine builders help their customers, not those that are buying crates. Because of that we’ve stepped up our role to help these guys out. I don’t mind helping a racer however I can with any problem he’s got with his car. And because a lot of the crate racers are new to racing, the questions we get can be all over the place. A lot of times when I’m helping somebody I’ll get a call from him every week for a month until he gets his engine tuned so that he’s getting good performance and great throttle response, and then once he gets things nailed down I won’t hear from him again.”