Sale ends todayGet 30% off any course (excluding packages)

Ends in --- --- ---

Understanding AFR: Introduction

Watch This Course

$89 USD

Or 8 weekly payments of only $11.13 Instant access. Easy checkout. No fees. Learn more
Course Access for Life
60 day money back guarantee



00:00 Tuning an engine using EFI can be broken down broadly into two separate operations Setting the ignition timing and setting the AFR or air fuel ratio.
00:11 Sure with modern engines there is a lot more peripheral stuff happening, such as cam control, boost control and e-throttle, but if we come back to the bare basics, we are left with fuel and ignition.
00:23 Setting the ignition advance in some ways is quite straightforward since we have the torque feedback from the dyno to tell us when the ignition timing is optimal.
00:32 The MBT tuning technique which we use for calibrating ignition timing is discussed in our EFI Fundamentals course.
00:40 Choosing the AFR to run an engine at is a little less clear cut since at most points in the load and RPM the engine will run adequately across a fairly wide range of AFR sometimes with little effect on torque and power.
00:55 Getting solid information on how and where to set the AFR has always been a problem, with most tuners not wanting to commit to providing a specific answer.
01:05 This has meant choosing a suitable AFR has traditionally been a grey area, which can be confusing and daunting, particularly when you are just starting out.
01:14 This course will remove any confusion, giving you the answers you need to safely tune an engine and produce good power, economy and reliability. More importantly it will give you a thorough understanding of what AFR means and how it will effect your engine and your tune.