The problem with the Quadrajet is that when the secondaries open up, it tends to break the tires loose, so they're really sensitive to tune. He sends me his motor to run on the engine dyno, and it's just about impossible to properly adjust the secondary function to produce best track performance.
Just because it can be made to run clean on the engine dyno doesn't mean it's going to handle the transient loads presented at the track. I feel like the engine dyno is the best for doing research where you're looking for maximum power. You can't do this on the chassis dyno.
For example, if a customer doesn't bring me the same tires and rear gears he runs at the track for testing on the chassis dyno, we won't get the same readings (power levels) he'll get at the track. They always want to compare power levels with their buddies and I have a hard time convincing them that's not the reason you use a chassis dyno. There are just too many variables involved.
I can change rear tire pressure and change the power. Chassis dynos are unbeatable for getting best on-track driveability. At the end of the day, each type dyno has its own purpose, just like any machine, and you've got to choose between them based on what you're trying to accomplish.
The one thing I want to emphasize is for racers to not misunderstand what they can and can't derive from testing on either of these types of equipment.
On the track, the load sensed by an engine during acceleration is not constant. If fact, it decreases as the mass of the car is accelerated, up to the point where aerodynamic resistance overtakes lower speed inertial resistance. Unless an engine dyno is built to accelerate a mass, like a heavy flywheel that simulates car weight, you can't determine transient load conditions as a car experiences on the track. A chassis dyno will at least approach this condition where an engine dyno can't.
As I previously said, WOT power measurements should be confined to an engine dyno. Any other type of power evaluation or tuning conditions belong on a chassis dyno.
As professional engine builder, what is the most difficult part to becoming successful?
I guess it boils down to developing an ability to deal with a wide variety of customer personalities. Different people want to be treated differently with respect to what they expect from you. For example, I have this longtime customer who called me eight times today. I mean, if every customer called me that many times a day I'd never get anything done. But you just have to learn how to deal with it. It's like any business where you need to learn the personalities of your customers to know how they want to be treated as well as how they treat you. Of course, we all have an ego and it's really important to not only recognize your own but those of your customers.
In your recall, what's the most successful project you've completed?
That's easy. I think putting in our SuperFlow chassis dyno and beginning to run Sprint Cars on the rolls is it. I mean, nobody had ever done that before. Even the SuperFlow engineers gave us a blank look when we told 'em we wanted to start to run Sprint Cars on the dyno. Even they didn't know if it would work. And you can't imagine all that we've learned using that technique.
Of course, once we did it, seems like a lot of other shops started doing the same thing. It just makes sense. We've now been doing this for about 11 years with no dyno problems at all. In fact, I've got 14,800 runs on that equipment, maintenance-free. I think I've greased the U-joints one time. Can you imagine that? Especially when you're starting Sprint Cars on the rolls, in gear and with all the shaking and counter-loading going on. It's brutal.
Also in your recollection, what is the most humorous experience you've had?
Well, we've had our share of these but probably the time a guy left a rag under his carburetor. He put on the carburetor, engine wouldn't start, having all kinds of problems, called me up and he finally managed to get it started. He called me again and said he had bits of rags shooting out all the headers and wanted to know what he should do. Funny thing is he didn't damage anything but he said there was red lint going everywhere. I'd like to have seen that one myself.