06/20/2026
Very well said, my friend.
I wanted to take a moment to address some of the comments and reactions to the fuel/lambda chart that David Crane of Fast Tunes and shared recently.
The purpose of the chart was simple: education. It was never intended to be the final word on tuning, nor was it meant to replace proper testing, logging, measuring ethanol content, or real-world experience. It was created to help people better understand the relationship between lambda, gasoline AFR, E10 fuel, and E85.
What surprised me wasn't that some people disagreed with the chart—that's perfectly fine. Healthy discussion is how we all learn. What was disappointing was seeing a few individuals and shops immediately jump to personal attacks, dismissive comments, and attempts to tear down something that was posted with the sole intention of helping others.
The reality is that many enthusiasts and even experienced tuners still reference AFR numbers without fully understanding what fuel they're actually working with. Someone may say, "I tune everything at 13.5 AFR," but if they're running typical E10 pump fuel and not measuring ethanol content, that 13.5 gasoline AFR equivalent may not represent the actual mixture they believe it does. That's exactly why charts like this exist—to provide a simple reference point and help people understand the differences.
Neither David nor I are claiming that a chart replaces a wideband, fuel testing, data logs, experience, or proper tuning practices. It's simply a tool to help educate people who are trying to learn and better understand the fuels they use every day.
At Fast Tunes and GMR Performance, we believe that sharing knowledge helps strengthen the entire performance community. The goal was never to prove who knows more than someone else. The goal was to provide useful information that may help someone avoid confusion, make better tuning decisions, or simply learn something new.
The performance industry is small. There is room for discussion, disagreement, and different opinions. What there shouldn't be room for is the constant need by some people to attack others who are trying to contribute and help the community.
At the end of the day, David Crane of Fast Tunes and I will continue to share information, answer questions, and help where we can. If some shops choose to spend their time tearing down others instead of contributing something useful themselves, that's their choice. Most enthusiasts can tell the difference between someone trying to educate and someone simply trying to criticize.
We're here to help. We're here to learn. We're here to share knowledge. And we're here to make better-informed tuners, racers, and enthusiasts. That's all this chart was ever meant to do. Use the chart and use your own ideas on what you like to target Fasttunes
