As the money and competition in the Nextel Cup Series have skyrocketed in recent years, the image of a Nextel Cup engine builder has changed. The old mechanic who learned about engines working in his daddy's garage is still there, but working right alongside him is a mechanical engineer who spent his youth studying the laws of thermodynamics. It's a different world from the old days (Maurice Petty told us once that he used to scrounge junkyards looking for parts for Richard Petty's cars), but that's OK because that's what is needed to continue the pace of innovation.
Much of that innovation, however, doesn't come from inside the engine shop but from outside sources. Many of the advancements in race engine technology actually come from the parts manufacturers working closely with the race teams to give them what they need. That's the good news for a Saturday night racer. After all, the last thing a Nextel Cup team wants to do is pass along its discoveries to anyone else, but an innovative parts manufacturer can take what it learns racing on the Nextel Cup level and use that knowledge to help everyone go a little faster.
Advancements in camshaft grinding...
Advancements in camshaft grinding technologies have improved the surface finish on the lobe so that in some cases, for the cash-strapped racer, micropolishing isn't a necessity.
To find out more about how high-end racing affects the little guy, we called up the folks at Compe- tition Cams and asked a few personal questions. Comp Cams is a perfect example of this phenomenon because the company produces a wide range of engine parts and is a big player in everything from Nextel Cup, to drag racing, to Saturday night stock cars, all the way to go-karts. Interestingly, there's a lot more going on than we originally thought.
Camshaft Technology "When it comes to the camshafts, the demands of the Nextel Cup and Indy Car teams that we work with required us to go to great lengths to meet their specs," says Chris Brown, Comp's vice president of operations. "But once we figured out how to meet their requirements, it was relatively easy to continue those improvements to our other cams.
"The number one thing that we've done is have our camshaft design team work with every type of engine out there. We've got three cam designers, and instead of having them specialize in certain types of engines, they all work on everything from Nextel Cup, to Top Fuel drag racing, to street cars, to oval track stock car racing. They even do the cams for go-kart racing. That's really paid off for us because of the depth of knowledge that those guys have acquired. They understand what's happening inside an engine a lot more than somebody who only has access to one style of engine. So now when they encounter a problem for a Saturday night race engine, they can draw on their experiences with how drag racers or Nextel Cup racers solved a similar problem.
Super-precise measurement equipment such as this Adcole machine allows cam grinding technicians to repeatedly check their work and hone their procedures until they are able to hold previously unthinkable tolerances.
"The upper-level guys are always raising the specs that they need for their products. That's why we acquired an Adcole machine that checks cam tolerances. But what happened was our guys on the manual cam grinders started using it to tune up their machines and methods for all their stuff. In the past couple of years, they have gone from having a window on their duration specs from 0.5 to 0.75 of a degree down to 0.2 to 0.25. Without having to tell them, their own pride in their workmanship has brought them down that path.
"We've also learned a lot about surface finishes, what works best on a roller (cam) and what works best on a flat tappet. We've taken what we've learned from micropolishing and used it to test different types of grinding stones so that the stone itself leaves a different finish on the cam lobes. That's helped us improve the lobe surface finish for guys that don't want to or cannot pay for micropolishing. All that stuff is directly related to some of the high-end cams we have done for NASCAR teams because they often put a spec on the surface finish.