One big advancement that didn't exist in 1983 is performance coatings like this DLC coating on this wristpin (right), which significantly reduces the chances of the pin galling inside the pin bores in a dry-sump engine pulling a lot of crankcase vacuum. Photo by Jeff Huneycutt
We're still racing solid, flat-tappet camshafts and lifters, but they have made tremendous improvements over the years. Twenty-five years ago, in many applications, we were still using stock core castings for the camshafts and stock lifters. That really limited the power you could make, and the longevity wasn't good, either. Flat tappets have their limitations, but some of the manufacturers have really been able to squeeze quite a bit out of them. But that has come at the expense of cost, of course. The durability has been helped by improvements in materials used and the tolerances the components are held to, but you are going to pay for it.
-Keith Dorton
Cylinder Heads
We probably spent more time porting cylinder heads than working on any other single component. That was because back then, there was no such thing as CNC equipment, and everything had to be done by hand. Once the aluminum cylinder heads came along, they were easier to cut, but the raw cylinder heads were still pretty much a cube of aluminum. You could barely fit a crayon inside the intake port.
Doug Yates (right) speaks with his father, Robert, in one of the RYR dyno cells. Doug says the development of advanced test equipment has allowed engine builders the freedom to experiment, without the fear of having to test untried components on the racetrack and contributed significantly to the sustained level of progress we've seen in engine technology in the last decade. Circle Track Archive
It was definitely more fun for me back in '82 and '83 because there was so much creativity involved. At the time, I was working at DiGard with Robert Yates and Bobby Allison was driving. As time went on, we started finding more ways to modify the cylinder heads. Then, later on, when we went to the Ford deal at Harry Rainer's with Robert, it really took off. We'd take the standard Ford cylinder head and start welding it up so we could cut it up even more. Then, we'd move both the valve angles and locations. The more we'd find, the more we'd change, and it got to the point where we'd come in in the morning and say, 'OK, where are we going to put the valves today?'
That Ford head was a canted valve configuration, so it looked like it was blown up anyway. So, when we started moving the valves around, they really didn't notice it-plus it didn't say anything about it in the rule book. That, of course, was the beginning of the Ford Yates head they raced for so many years.
Today, you can complete a head so much faster because you can put it on a CNC machine and let it go to work. A CNC is also really good because it is so consistent. But I still think there is something lost because a classic head porter has gotten so rare. He's the one sitting around working on a port every day, and while he's working, he's thinking-coming up with new ideas and things to try. They are a different breed of people, the old head porters.
-Larry Wallace
Performance Coatings
Coatings are another area that has really improved performance. When we first started really sealing up the engine and pulling a lot of vacuum, we couldn't get an engine across the dyno and to the track to test. We started using piston and pin oil squirters, and we actually had to vent the bottom end of the engine. But what really helped solve the problem was the development of DLC (diamond-like coating) on the wristpins. That really helped stop the problem we were having of the wristpins galling to the pistons. Without that coating, we wouldn't be where we are today with the power we can make pulling vacuum in the crankcase. Other coatings have also helped in other areas, but that is the big one to me.
-Doug Yates
Competition
One thing I will say that has gotten tougher, is the demands a racer will make. You could go to any racetrack 25 years ago, and you might find four or five cars capable of winning. Whether it was Nextel Cup or a local dirt track, the difference in lap times between the First-place car and the Last-place car might be a second-and-a-half. Today, there are usually 14 cars capable of winning in just about every division at any track you go to. And then, the difference in lap times between the top car and the tail of the pack may be 0.4 second.
The competition has really improved, and that's a good thing. I'm glad to see it, but that puts the burden back on the engine builders. The rules are so strict that we're all running the same stuff, so you really have to think and work hard to find any little advantage you can get.
-Keith Dorton
Conclusion
A lot has changed in the motor biz in the 25 years that Circle Track has been around. With competition as tight as ever in all forms of racing, it's a safe bet that engine builders around the country will be constantly refining and reinventing better ways to make more power. Where will it go in the next 25 years? That's anybody's guess, but stick with us and we'll find out.