NHRA - National Hot Rod Association

The birth of the data recorder

12 Dec 2014
Phil Burgess, NHRA National Dragster Editor
Ron Armstrong, standing, and Dale Armstrong pore over data printouts from an early RacePak data logger.

“People ask me what was the single thing that made the biggest progression in drag racing from the 1970s, when no gains were being made, and I tell them it was the computer. It changed the sport in a way nothing else did. There’s nothing else that even comes close. Front-engine dragster to rear-engine dragster was nothing compared to what the computer did. That was one step, and it was over. The computer went on and on, and to this day it’s still doing it.”

The speaker is the late Dale Armstrong, and the voice is coming off a digital file sent to me by Tim Anderson, president of Racepak, from a near-two-hour interview he did with Armstrong in the fall of 2013. It was a melancholy feeling to hear Armstrong’s voice again, knowing that I’ll never hear it again any other way, but I was thrilled that Anderson generously offered it up to me because I had already planned to try to relate the story of how on-board data recorders — required equipment ever since — first came into use on the dragstrip in the early 1980s, and without Armstrong’s own comments, it would be sorely lacking.

Armstrong’s wife, Susie, had already sent me the phone number for Ron Armstrong (no relation), who, along with Spencer Eisenbarth, created Competition Systems Inc., which developed the recorder. I don’t remember seeing anything that really explained the trials and errors of what has become such a crucial component on any top-class car, and after an hour-long phone call with Armstrong, I’ve tried to distill the basics of that experience below that, when combined with the Dale interview, paint an interesting picture.

[Note: From this point on, to keep the story straight, I’m going to refer to the two Armstrongs as Dale and Ron. I ask that my journalism professors and copy editors forgive me.]

In the recorded interview, Dale explained that even early in his career, during his alcohol-racing heyday, he was looking for some sort of data capture or electronic advice, relying on everything from telltale tachometers that would show the highest rpm experienced on a run to a supercharger boost gauge with a check valve that would hold the highest pressure and even the simplest things like a dash-mounted red light that would signal loss of oil pressure.

He related a humor trial-and-error story about trying to develop a positive engine shutoff after snapping the shaft in the quick-change rear ends he ran in his AA/DA dragster and got an assist from “a guy that did electronics work on IndyCars. We put it on the car, and Mike [Guger] and I went to Fremont. We were in the pits warming it up on jack stands, Mike was in the dragster and I was out there by the engine, and, man, it blew the blower off. The next thing I remember was being 15 feet away and on my back, and blower nuts and studs were still coming down from the sky.”

Scratch that idea.

Yet after dominating in the alcohol ranks in the late 1970s, Dale switched to nitro in 1980, and he admits to having “all of these unanswered questions” still rattling around his inquisitive brain.

He was especially befuddled on how there had been so little progress in performance form the mid-1970s to the early 1980s — Don Garlits’ famous 5.63 Top Fuel pass was the quickest ever from late 1975 until early 1981 — and he surmised that there were many secrets to be unlocked.

He was not alone in those thoughts. Henry Walther, for years a key member of the Larry Minor/Gary Beck team and a follower of electronics-savvy Formula 1 racing, was intrigued by the idea of being able to find out exactly what was going on during a pass beyond and more accurately than what a driver’s feedback could relate (sometimes incorrectly).

The fifth wheel on the Minor machine was connected to the rear-axle housing of the car and incorporated an inclinometer for measuring the angle of the suspended trailing arm that supported the wheel. Back in the pits, with the data in hand, the team could jack up the rear of the car to replicate the same angle, then measure how far the tires were off the ground and determine the diameter of the rear tires at various points on the track. Low tech, but effective.

Remembers Walther, “In 1983, when we won Top Fuel at Indy, John Norcia of Ram Clutches brought an engineer into our trailer and asked Gary if he would be interested in a device that would monitor the engine rpm, driveline rpm, exhaust-gas temperatures, and a couple of pressures. Over that winter, we installed their recorder on our car and started working with them in developing this system. There were still problems to be worked out, but this was the system that gave us the first on-track, full-throttle data starting in 1984. It was also the system with which we incorporated a fifth wheel at the rear of the car to try to determine tire growth. At that time, Goodyear wasn’t able to provide us with tire-growth information at speeds above 250 mph, and that in turn prevented us from accurately determining whether or not we were locking up the clutch or simply spinning the tires.

“As the season progressed, there were successes and failures with the system. We would run it at a race, and then we might be without it for a few races as it went back to the builder for upgrades. It was during one of these hiatus that a friend of mine, Greg Long, mentioned to me that he knew a fellow who was working on a system similar to what we were using and would I be interested in meeting him. He arranged a meeting between this fellow and me at a local Mexican restaurant. Greg left after the first hour of conversation, but the other fellow and I talked until they threw us out at closing time. This guy turned out to be Ron Armstrong. I could see that Ron and Spencer had developed just what I had been trying to accomplish with my feeble attempts. Unfortunately at that moment, I wasn’t able to bring it onboard on our car, but knowing that what Ron had was something we all needed, I told him I was going to introduce him to another friend who had also been beating his head against the wall in trying to obtain on-track data. I then called Dale and put him in touch with Ron Armstrong.”

Dale knew that the Beck team had been getting data and in late 1983 had gone to his old friend, Jim Foust, who had been a partner on some of his most successful alcohol cars. “Jim was a computer guy who worked at TRW and told me he could build me a computer to capture the data,” he recalled, “but it took up the whole front of the car. We ran that thing for about three months and never got anything out of it. The RF [from the magnetos] would just kill everything.

“Henry Walther told me about Ron, so I went to where worked and introduced myself. He starting talking and after about two sentences, I didn’t know what he was talking about; he was using words I’d never heard. As I got to know him, I told him that whenever I got lost, I was just going to say, ‘Stop. Start over. What the hell are you talking about?’ “

Timex Sinclair computer with thermal printer

Ron, whose primary early forte was engine building, was employed at Dresser Industries, where he had been working intently on capturing data on the dyno and later focusing on engine rpm over time that would enable road racers to better select gear ratios. He had set up a dyno to try to monitor power bands and soon hired Eisenbarth, a bright and inquisitive young mechanical engineer to assist, and ultimately became his partner in the company. It was Eisenbarth who suggested the use of a histogram. They experimented with recording rpm as a tone and unraveling it from there, but it was too cumbersome. Even after he left Dresser, they continued to collaborate, and it was Eisenbarth’s discovery of the Timex Sinclair, a small DOS-based computer that came with a thermal printer, that provided the great breakthrough. By the early 1980s, they had learned how to graph this data with a series of dots printed on thermal paper.

Through some savvy investing during the time he was driving the Miss Budweiser Hydroplane in the early 1980s, Ron was able to pour some seed money into the project to have some specialized circuit boards made. The company’s name was Competition Systems Inc., and the product itself was named Racepak (which later became the company name). The first Racepak went into competition vehicles in 1984, on hydroplane boats and stock cars, and the primitive data was eye-opening and, to some, not believable.

“Some of the rpm dots on the boat went as high as 5,800 rpm, and I remember the owner telling me there was no way it was that high because the crankshaft would have broken,” he recalled. “I took it out because I thought something was wrong, and not long after that they did break a crankshaft. When I put it in one of Harry Hyde’s NASCAR car, we were still only capturing rpm, but we were seeing some spikes, like the tires were coming off the ground. Before long, the shock guy realized that it was an issue, and we worked on that until the lines flattened out. I remember Harry saying, 'I can’t believe this guy hooked a wire on my spark-plug wires and can tell me that my rear shocks are bad.’ "

(The first units had only rpm and on/off throttle measuring — not position — and additional analog channels were added along the way. They sampled data just 10 times per second because memory was incredibly expensive back then; today’s units can record more than 50 channels and many, many more sub-channels and sample more than 50 times a second.)

The Reher-Morrison-Shepherd Pro Stock team was the first to use the new RacePak data logger (below) on the dragstrip.

The Reher-Morrison Pro Stock team of David Reher, Buddy Morrison, and driver Lee Shepherd were the first to run the Racepak on the dragstrip in early 1985, and that showed them some inconsistencies in Shepherd’s driving and became instant converts. Not long after, the two Armstrongs got together and forever changed the face of nitro racing.

It took a lot of experimenting, frustration, and trial and error with various forms of shielding and the installation of carbon plug wires before the rpm data became reliable, and the next thing they got was driveshaft speed, which was another eye-opener.

“Everyone thought we were revving 9,000 rpm, but we were only going 7,000, nowhere near what we thought we were,” recalled Dale, “but getting rpm and driveshaft was the most important thing we did because we saw it was still slipping 700 rpm going across the finish line.”

(It’s important to remember that, unlike today’s PC-based readouts, which allow crew chiefs to overlap multiple color-coded, line-graph channels of data for cause and effect, in those early days each channel of data was printed out in a series of dots on a roll of thermal paper. It was only by placing data sheets atop one another and shining a light through both that you could see the overlapping data points. Interpreting all of this, and being able to create the scale for each readout, was time-consuming and often frustrating. “We didn’t know everything,” Ron admitted. “Sometimes it was like the blind leading the blind.”)

The discovery that the clutch was not fully locked up at the finish line led to the creation of the lockup clutch that applied additional fingers downtrack, but that, too, involved some trial and error.

“In about a month, we built a lockup clutch,” said Dale. “The first iteration of it was just wound-up springs holding the arms out, and we had a knob on the end, and pneumatically we were just going to drive a piston into the bellhousing and knock these three levers loose. We went to Milan, Mich., on a Saturday night. It was just getting dark. It got to about half-track, and sparks started flying out of it. We went back to the pits and pulled the bellhousing off, and these springs, which were pretty substantial, about an eighth-inch in diameter, were all straightened out and wound around everything. Well, that didn’t work.

“I was always trying to control those arms, and at the time I didn’t think that the throwout bearing would survive. Finally, we did it that way, and the throwout bearing was the least of the problems.”

The design, with the help of an engineer who worked with Ron who designed the clutch arms to Dale’s specs, was perfected in mid-1986 and led to a huge performance leap for the Budweiser King, highlighted by a stunning 5.50 at 271 mph at that year’s U.S. Nationals. That run famously (and, for them, unfortunately) was recorded on a bye run that allowed their competitors to hear the engine pitch change downtrack. The cat was soon out of the bag.

More and more data-recording channels were added to measure just about every mechanical aspect of the car. Key among them was an accelerometer, or G meter. “It was one thing after another, but what I realized right from the start was the G meter,” said Dale. “Most people didn’t pay a lot of attention to it, but, man, that thing told you everything.”

Interestingly, initially Dale was not interested in capturing exhaust-gas temperature (EGT), another of the great and useful tools to determining the efficiency of a cylinder (and in detecting dropped cylinders); it wasn’t until they measured EGTs on Darrell Gwynn’s quasi team car and saw dropped cylinders being recorded that Dale saw the light. “It was one of the few times that something Dale said turned out not to be technically correct,” said Ron with a laugh.

While the Bud King and R-M-S teams and Jim Head were early adopters, there were famous racers who were more reluctant.

For five years in the late 1980s, the Bud King camp was the public face of the RacePak. Here, Dale Armstrong, second from left, and Ray Alley, second from right, explain its benefits to a number of interested racers.

“[Don] Prudhomme was one of the holdouts,” recalled Dale. “I told him I’d give him a unit and help him read it; after the weekend is over, come pay for it or give it back. I told him you can’t race without it if you want to be competitive. I told him you can pay me now or you can pay me later, but you have to have it; there’s no way around it.”

“Some of the old-school guys, like Austin Coil and Dick LaHaie, welcomed it with open arms, but I do remember Don Garlits was resistant,” added Ron. “Then I remember him calling me one day and saying, ‘I should have embraced this system the first time I saw it. I was the biggest bonehead ever. I want whatever you’ve got. Whatever you’re thinking you might have, I want to get back on the leading edge.’ “

Although Ron and Eisenbarth continued to upgrade and improve the Racepak over the next 20-plus years before Ron sold the company, the two Armstrongs collaborated on other projects, including the use of stronger, rare-earth magnets in the magnetos and, most intriguingly, a traction-control system they tested on the Budweiser King Funny Car prior to the 1989 season.

Dale had previously experimented with a semi-automated braking system that would control how long the brakes were applied during the launch. Based on his observation of the car’s dry hop, Dale could adjust this feature using toggle switches on the car’s rear bumper. That led to his asking Ron to develop something that would react to excessive driveshaft speed.

Recalls Ron, “The original rule stated that no micro-processor control of the brakes could be used, so we built the system using all discreet components, which turned out was much harder than if we could have used a processor. The system used an electronic reference ramp and compared it to the current driveshaft speed. If the current speed was greater than the set ramp, it would apply the rear brakes in proportion to the amount of deviation. Everything was done using fiber-optic cables and hidden in the bottom of the puke tank, not to hide it from NHRA but from our competitors.”

Some of their competitors obviously got wind of the system — probably by noticing that the car would hook up after a smoky dry hop or that Armstrong was no longer manually fiddling with something at the back of the car — and complained to NHRA, who changed the rule to read only that the driver could control the brakes.

Even though he no longer owns Racepak, Ron’s advice is still sought by many, most recently John Force Racing, who engaged him a couple of seasons ago to look at various facets and work on special projects with Jimmy Prock.

There’s little doubt in my mind that the data recorder has led us to where we are in terms of ever-increasing performance in the nitro ranks — this year fans saw the quickest and four fastest Funny Car runs in history — and, along with other continuing developments in hard parts, will continue to lead us into the future.