Tech Talk #75 – Year-End Observations

DavidTechArticlesBy David Reher, Reher-Morrison Racing Engines

“A great car setup can’t overcome a bad engine, and a terrific engine can’t win in a lousy car.”

Although it’s been several years since Reher-Morrison Racing Engines last competed full-time in NHRA Pro Stock competition, I still follow the category with interest. The fact that we have expanded our engine business with customers competing in classes ranging from Pro Mod and Top Sportsman to tractor pulls and 400 mph Bonneville land speed racers has given me a fresh perspective. Since this issue of National DRAGSTER celebrates the accomplishments of this year’s Pro Stock champion, I thought I might offer some observations on the state of the class.

Mike Edwards certainly deserved to win the Pro Stock championship. I’ve seen him develop his skills over the years. I remember when he won Indy in 1998 using a Reher-Morrison engine – and there were times that he ran quicker with our engine than we did. Given the intensity of the competition among the top Pro Stock contenders this year, it was a tremendous achievement for Mike to qualify in the top spot sixteen times and then put together a perfect race in Richmond during the stretch run for the title.

The same principles apply now as when the Reher-Morrison team won its first NHRA championship in 1981: To take the Pro Stock title, a racer needs big horsepower, a good race car (loosely defined as the chassis, clutch, suspension, and aero setup), and a sharp driver.

There was a time when racers like Bob Glidden and Warren Johnson could gain four or five hundredths of a second on the competition in the last half of the run. That kind of horsepower advantage is history now – today the top teams work relentlessly to find a few thousandths. In the current state of competition, a great car setup can’t overcome a bad engine, and a terrific engine can’t win in a lousy car.

Edwards had the complete package this season, and consequently he was able to beat his rivals at every increment of the quarter-mile. In one session at the Mac Tools U.S. Nationals, Mike outran everyone by four hundredths of a second – he was a hundredth quicker in the first 60 feet, a hundredth quicker from 60 to 330 feet, a hundredth quicker to half-track, and a hundredth quicker in the back half. When Edwards set the Pro Stock record at XX in Richmond, Greg Anderson was a thousandth of a second quicker in the back half, but Greg’s car didn’t run the first half as well. That was a decisive moment in the championship chase that gave Mike momentum.

It’s my belief than no one in Pro Stock has more horsepower than Edwards, although there are probably several cars with at least equal power. He simply did the best job of putting together superior performances on every part of the track, and the championship was his reward.

I’ve written frequently about the impact of Pro Stock technology on sportsman drag racing engines. The transfer of knowledge has made sportsman engines more powerful, more reliable, and more affordable in terms of cost per horsepower – to put it crudely, “more bang for the buck.” It amazes me, though, when racers don’t take advantage of the power that’s readily available because of misinformation and mistaken beliefs. A case in point: conventional versus spread-port big-block cylinder heads.

The standard Chevy big-block cylinder head with siamesed intake ports dates back to the mid-Sixties, when Chevy engineers had to fit their new “semi-hemi” engine under the hoods of Corvettes and Camaros. Twenty years later, Pro Stock racers introduced the spread-port concept with raised and relocated intake runners. Aftermarket manufacturers have continued to evolve and develop the spread-port design, such as Dart’s Big Chief head, Brodix’s Big Duke, RMRE’s Raptor head, and others.

In my experience, racers always want to go faster. It’s imperative to improve performance in the “go fast” eliminators such as Top Sportsman, Top Dragster, and Quick 16. Speed is also an advantage in heads-up Super eliminators because the faster driver can judge both the finish line and his opponent in the final few feet of the race. Consequently I don’t understand why some racers in these categories continue to use conventional big-block cylinder heads when switching to spread-port heads offers a quick 100-horsepower tune-up. Most racers rely on the latest technology in computers and weather stations – why not in cylinder heads?

Perhaps their reluctance is a carryover from the perceived valvetrain problems of the spread-port design. True, the first spread port heads did have rocker arm problems – but that was more than 20 years ago, and new rocker arm designs and advances in pushrod technology have virtually eliminated reliability issues. A sportsman engine with spread-port heads is as reliable as an engine with conventional heads – and it’s potentially much more powerful on the basis of horsepower per cubic inch.

There is certainly a place for conventional cylinder heads, but it’s not in the “go fast” classes. The spread-port design has the advantages of smaller, more efficient combustion chambers, deeper valve bowls with a longer short-turn radius, and a superior airflow-to-valve diameter ratio. All of this adds up to a more efficient engine – so it’s pointless to give that up to avoid a problem that was cured years ago.

Not every racer has the desire or the resources to become a Pro Stock champion like Mike Edwards. But every racer has access to the advanced technology that’s been developed by manufacturers and engine builders. Why not take advantage of it in the New Year?