Thoughts on the Chassis Dyno
By Dr. Jamie Meyer
December 2007
I have been collecting and reading “car mags” since the mid-80s, when my childhood love of cars turned into my high school fascination. From reading thousands of hot rod magazines, I have become a huge fan of automotive journals and many of their writers both past and present. And, it’s been interesting for me to watch the development of these editors and their content as the huge automotive aftermarket has grown up with them. When you start to dissect a car magazine, there is more to it than just the “stories” and the “advertisements”. Those stories break down into all sorts of different topics relevant to the readers – or racers for Fastest Street Car. You’ll see event (or race) coverage, feature cars, and technical stories.
For my money, the technical stories have the most impact on the hobby. I say this for several reasons. First, a good editor reports real world applications for the latest parts – often on a car that’s just like the reader’s. Second, a good tech story incorporates parts from the magazine’s advertisers – allowing for them to have a solid review and detailed explanation of these parts for the reader. And, thirdly, a great tech story will pit several parts of the same type against each other so that the readers gets a great chance to see how these parts stack up before they buy one for their own application.
For the last decade, the chassis dyno (and engine dyno to a lesser degree) has been the tool employed by mag writers to flesh out good tech. This has been great. Technicians are able to start with a car, base line it for power and torque, then start swapping parts to monitor the results. Coming from a former scientist, I can tell you that I really enjoy the results that this type of study has brought the high performance aftermarket. Long gone are the days of “seat of the pants” reports on part swaps. And, while A-B-A drag strip testing can be extremely accurate, it has it’s set of variables.
The repeatability of the chassis dyno has also allowed more than one shop with a similar car to try the same part or combination of parts to further solidify the findings of the first study. You’ll see this all over the internet when similar parts are tried on the same car at shops at very different locations in the United States. If the part works on both cars, it will be proclaimed a winner. If not, well, the company that makes that part has some explaining to do.
Even more amazing to me is how drag racers have turned to the chassis dyno to greatly speed up their testing sessions. Coming out with a hot new class car? Chances are good that you’ll end up getting your baseline tune figured out on the chassis dyno. Is it a replacement for laps at the digs? Of course not, but it’ll get you real close.
The message that all of this sends us is that not only has the chassis dyno helped us evaluate parts, but, more importantly, it has allowed the industry to develop and entire generation of good, solid tuners that have helped us all maximize our performance cars. And, with a seasoned readership such as that reading this magazine, you already know that maximizing the combination that you already have is worth more than any new part. Having the luxury of a scientific process to hone in on the optimal tune-up for any given collection of parts has pushed this industry farther than any other technical breakthrough.
So, even if you aren’t a magazine writer, you can appreciate the impact that chassis dyno has had on our word. In fact, even if you’ve never had your car on a chassis dyno, the odds are good that the company that built the parts you are using has tested them on a similar combination on a chassis dyno. Happy dyno-ing!
E-mail me at: drmeyer@concentric.net
Some prevously published articles available online on our past MOMs participants:
Michael Young, Bob Restani, and little write up of Dr. Meyer himself.