The increase in final-drive ratio helped the "HP & TQ" engine significantly, and now the increased power of this engine is clearly evident at the end of the acceleration run. From this exercise we can note the following:
1. Gear ratio and engine speed may provide a performance gain in some (but not all) situations.
2. Optimizing final-drive ratio for each engine combination is critically important.
What is right for your track depends on the type of racing you do. On tracks that are very slick and with reasonably long straights, a higher rpm engine with the appropriate final-drive ratio may be fast. On short tracks with lots of grip, a higher torque engine may be best.
The purpose of this part of our series is to have you consider and plan what is best for your circle track effort. Be honest about the resources you have. Rank what are the five most important things for your type of racing, and spend your resources wisely. Remember, when you get passed from the flag stand to the corner, it is not necessarily killer power that got you. It is more likely the driver had a higher corner exit speed. Ask yourself what type of engine combination is best for your track, and make sure you optimize the final-drive ratio.
This was a beginning, intended to focus on the importance of engine performance and related elements in a winning combination. You'll need to step back and apply the information shared to your particular racing efforts. Determine priorities and rank them, not necessarily as provided here but in a similar fashion, according to how they fit into your scheme for winning-and then stick to them for consistency. If you allow priorities to change in the short-term, you'll have difficultly evaluating your original pecking order.
Next month we'll begin digging into the essentials of building a solid engine foundation, including parts longevity, bore/stroke relationships, and the essentials of good component selections and most important aspects of good oiling systems. You'll make some definable progress.
|CHART B |
| ||HP & TQ ||TQ ||RPM ||RPM |
|Baseline with 3.70:1 rear gear ||w/3:70 ||w/3:70 ||w/3:70 ||w/4:10 |
|Distance ahead of (or behind) |
baseline (measured in feet)
|13.1 ||2.9 ||-4.0 ||18.3 |
As we begin this "Technology Transfer" series, here's the plan Charles and I intend to follow. While each of us is an automotive engineer, we come from different sides of the track, so to speak. And, quite frankly, that's part of what makes this combination of experiences valuable to you. As such, it's possible for us to present the "what's" that work in concert with the "why's" that support the reasons. In this fashion, you'll be able to assemble some new "tools" for your racing program by benefitting not only from our previous experiences in designing and building engines and components but Charles' hands-on involvement with both Cup and (more recently) F1 powertrain development. To put all this in motion, we'll begin rather simplistically, but you can expect technical detail and depth to increase as the series is developed.
Where appropriate, you'll find data and graphs that support the concepts and ideas presented. And in every instance possible, we'll be linking this information with what is appropriate for racers engaged in just about any form of circle track racing, literally at the "racer level" where it counts. All reader comments and suggestions are welcome. By so doing, you'll help Charles and me provide you the most applicable and useful information for your racing experience. Enjoy the series.