As runners-up by just a fraction of a point in qualifying, Lennart and Birgitta were certainly feeling the pressure as the Autoshop entry was readied on the dyno. The stakes were high, but you'd never know it from the stoic Swede. The pair's demeanor was as calm and measured as the pressure was high. Following the three warm-up pulls, the team briefly surveyed the numbers and then moved into the cell for their tune-up. At this stage, a nervous competitor may have gambled heavily with an aggressive tune-up in the form of more timing and a leaner mixture. Lennart went straight for the valve covers. It was clear that the team from Florida had contemplated their move with a long and thoughtful process well before the final round. Rather than risk a crushing fall to detonation with a ragged top-end tune, Lennart chose to loosen the intake lash in a bid for more bottom-end grunt.
With resetting the lash, the engine was allowed to cool for the entire tune-up period prior to the final-scored pulls. Inside World, the crowd's attention was riveted to the action at the dyno as the engine was fired for the scored pulls. Once at operating temperature, the signal was given to begin the final scored runs. As in qualifying, Autoshop's Chevy pulled up the rpm range cleanly, with nary a trace of detonation, turning the torque meter with tremendous force. The first pull netted a 1289, an improvement of 3 2/3 points. Lennart and Birgitta looked on with quiet focus as the engine was loaded against the DTS dyno's absorber for the second pull. A 1287. With the next pull, the engine repeated within a tight range, scoring a 1288.
Although the Autoshop team had seen the raw numbers and score tallied on the dyno sheets, the crowd waited anxiously for the composite score numbers to flash on the scoreboard. Applause broke out when a 1288 appeared on the screen, the highest score in the competition so far. However, it was not enough to ease the tension the husband and wife team was experiencing, as Lennart was clearly hoping for more from the lash change. With a 1288 score and the lead, it all came down to what Kaase's engine would do.
The Moment Of TruthKaase was in control of the situation as the Pontiac was wheeled into the dyno cell. With all the scores in front of him, there was no ambiguity about what needed to be extracted from this potent mill. As with any true competitor, Kaase had played out every possible scenario in his head, and the score put down by Autoshop was formi-dable. Kasse's tuning partner, John Nobile, was absent on the day of the finals, with a racing commitment taking precedence. Fellow competitor and friend Ron Shaver stepped in to offer assistance to the two-time champion. Everything was riding on the events to unfold, and the crowd filling the floor was braced for a real showdown as Kaase's engine was fired for warm-up. The Pontiac was run through its required three warm-up pulls; Kaase and Shaver reviewed the numbers as the sheets came off the dyno's printer. The veteran engine men could see it was going to be close, with the initial pull being enough to cover the competition, but the score declining with the two subsequent warm-ups, as temperature effects took hold of the Pontiac.
After studied contemplation of the dyno data from the warm-up pulls, Kaase and Shaver moved into the cell to set the tune. The timing was bumped forward, while the carb's air bleeds were opened up. Apparently, Kaase was playing for the win. With the Pontiac's characteristic dropping of score through subsequent pulls, the engine needed to come out strong to make a sufficient average to take the win. Following the tuning change with a test pull, it seemed Kaase had found what he was after. Although the engine detonated going in, as seen only by Kaase, Shaver, and the officials working the dyno, the aggressive tune had added healthily to the score, surpassing the 1,300-point level. Still, there was worry in Kaase's face. He knew the detonation seen at the roll-in could prove costly in the back-to-back final pulls. We overheard as Kaase and Shaver conferred over whether to pull back some on the timing. In the end, the decision was made to let it ride. With over 1,300 showing in the test pull, it was just a question of how well the engine would hold on as heat and detonation effects whittled away at the output.
Kaase chose to allow the engine to sit for the remainder of the tune-up period, while the tension in the air continued to rise in anticipation of the final pulls. As the clock on the tune-up period expired, the officials called time, and the Pontiac was fired. After the mandated warm-up, DTS dyno operator Matt Boyer opened the throttle, loading the Pontiac at 2,500 rpm to begin a pull. Moderate detonation could be heard as the engine worked up the rpm range. Kaase received the sheet from the printout-a 1,290 score on the first pull, over 10 points down from what had been seen only minutes before during the non-scored tune-up pull. Heat soak while sitting idle cost points on the first money run. Going into the second pull, the Pontiac had gained even more heat, detonation was more evident, and the score reflected the situation, dropping to 1,256. By the final pull, the Pontiac was succumbing to the effect of detonation and retained heat, factors which feed one upon the other, causing the score to spiral downward to a heartbreaking 1,221. There would be no repeat for the returning champion this year.
While Kaase and those in the cordoned-off dyno area had seen the numbers, the crowd of spectators and competitors had to await the posting of the results on the official scoreboard for the tally. Within minutes, the final score flashed, a 1,255.67, putting Kaase in Fourth Place. The ecstatic Livernois team reacted with excitement, as the unexpected problems with the Pontiac entry had allowed them to finish in the money with Third. Emotion also ran high with the Bischoff crew, as Tony's cool-handed play of just laying down a safe number in the finals paid off with a Second Place finish. For Autoshop's Lennart and Birgitta, there was relief and jubilation as the couple embraced to celebrate the success of nearly a year's effort at putting together their mighty Engine Masters Chevy. The tall Swede from Florida has proven to the world that his engine-building talents rank among the very best as a new Champion reigns in the Engine Masters Challenge.
The Power To WinLeading off our second day of qualifying, the husband and wife team of Lennart and Birgitta Bergquist of Autoshop Racing Engines rolled their big-block Chevy entry into dyno cell one. The native Swedes are based in Orlando, Florida, and if anything was notable about their entry, it was the clean but conventional look of their innocuous-appearing Chevrolet. This big-block certainly did not carry with it a threatening aura, with a 4150-series 850 Holley in a field of Dominators, and none of the custom one-off external plumbing distinguishing some of its competitors. In fact, externally it had the appearance of a typical big-block Chevrolet, the kind that looks at home sitting in the engine bay of a street-bound Chevelle. Even though it was only the third engine to run in qualifying, it was clear to anyone who really understood the numbers that the 1,285 composite score put down by the quiet Swede would be hard to beat. The engine literally came down like Thor's hammer, thumping the dyno with 844 hp and 740 lb-ft of torque in qualifying. (You can expect a complete feature story on this mighty Chevy in our March '06 issue.)
Following the theory of a relatively small-bore/large-stroke combination, the Autoshop entry achieved its 509 ci with a bore size of 4.250 inches and a stroke of 4.480 inches. Lennart unassumingly cited the successful under-square combinations in previous Engine Masters events in selecting this configuration. A 6.350-inch rod length was used, primarily because Lennart wanted to drop the ring pack down on the custom CP pistons, and have pistons built with thick crowns for strength. As Lennart put it, "That was the longest rod that I could put in it with the other parts." We inquired about the compression ratio and Lennart informed us that the ratio was set at an unusually conservative 11.5:1. Relating his experience in last year's event, Lennart explained, "Last year I had 12.5:1, and I got here with a 30.3 barometer, and the motor just detonated itself to death. That scared me quite a bit, so this year I was not going to do that again, so I limited it to 11.5." Lennart continued, "I may be backed-off a little too much for the weather we have now, but I did not know that when I designed the motor. I just had to figure that we would have similar conditions to what we had last year."
Things were a little trickier inside, with a billet Sonny Bryant crank featuring undersized 1.88-inch rod journals and small-block-sized 9.270-inch piston pins. The idea here is to lighten the assembly and give the engine less weight to accelerate, with a bobweight of only 1,640 grams. Lennart elaborated on the crankshaft: "I had Bryant cut the counterweights down really small, so small he almost didn't want to do it, and then I put heavy metal in there to balance it." Lennart didn't really admit much else in terms of windage control, "I didn't do anything other than bolt on that (Steffs) oil pan, and it has that screen in it." Besides the light internal weight, Lennart was able to build the engine with dramatically reduced rotational friction. Part of the credit goes to the ring pack, consisting of SpeedPro 0.043-inch rings, aided in sealing by gas ports in the piston tops. Lennart disclosed that the complete assembled engine, with just the plugs removed, required only 24 lb-ft to rotate, complete with valvetrain, while the short-block required only 12 lb-ft-that's slick!
As with may of the entrants, Lennart's engine took advantage of modern coating technology for an edge in friction reduction and thermal management. The rod and main bearings are coated with a friction coating, while the pistons received a friction coating on the skirts and the crowns received a thermal barrier. Up top, the combustion chambers, exhaust ports, the face of the intake valves, and the face and back of the exhaust valves all were treated to thermal-barrier coatings. The Brodix oval-port manifold received a thermal dispersant.
Some of the key components to putting down healthy power numbers are the choices in heads and the cam. From the results, it was clear that Lennart was right on target with his component selection. For cylinder heads, Lennart selected Brodix raised oval-port castings, which were fully ported by Mike Horney, who also ported the intake manifold. The intake valves measure 2.300 inches, while the exhaust valves spec out to 1.880 inch. The resultant flow as measured by Lennart was 380 cfm on the intake ports and 280-plus cfm on the exhaust side. The cam, a roller follower grind which rides in needle-roller cam bearings, was speced by Lennart and ground by Competition Cams. The cam features 258/260-degree duration at 0.050-inch tappet rise, and was ground on a 108-degree lobe separation angle, installed at a 106-degree intake centerline. Lobe lift is 0.460 inch on both the intake and exhaust; however, the intake rockers are 1.8:1, while 1.7:1 is used on the exhaust. Figuring the rocker ratio, the valve lift works out to a theoretical 0.828 inch on the intake and 0.782-inch on the exhaust-serious numbers in the pursuit of serious power. Exhaust flow was enhanced by the use of Stahl 2 to 2 1/8-inch stepped headers.
The Autoshop team's hard work and expertise certainly paid off with an impressive win in this year's Engine Masters Challenge. While some of the key components that made this impressive engine perform have been highlighted here, as might be expected the details go much deeper. We'll be revisiting this engine in greater detail to reveal just what it took to build this champion.
Engine SpotlightPhr's 2006 Feature EnginesWe went away from this year's Engine Masters Challenge determined to bring the innovative technology in these powerplants home to the readers. The simple specs belie the true level of execution and know-how that goes into these monsters of power. How did the builders do it? It's the details and execution that make the difference, and these builders didn't get to the top of their field by just opening boxes and bolting parts together. The thought process involves visualizing how each part interacts in the system that makes up the finished engine and taking steps to optimize the package along the way. You might not want to follow each of their moves to the full extent, but understanding what was done and why goes a long way to improving anyone's power-making game.
To really dig into the nuts and bolts, we were far busier at this year's Challenge than just running the show. Ace lensman Hunkins busted hump for the duration of the week, capturing images detailing these stout powerplants, both before the competition and during teardown. While traditionally only the three winning engines are torn down in the normal course of the post-competition tech inspection, this year we requested that some of the other competitors subject their engines to teardowns, just so we could have a look and record what we found inside. Fortunately, the builders were willing to comply, giving us an unprecedented level of detail in documenting these mills. Here's a brief on the Second-Place BES and Third-Place Livernois entries, as well as a rundown on four other engines we will be featuring in upcoming issues of PHR.