If you think these engines look powerful bolted to the dyno stands, you should hear them m
With the seven participating Hemi Challenge engines at the Competition Cams research and development center, and the new Superflow 902 dyno installed in the test cell, the fun part of our competition was about to begin. Exactly how much power would these engines make? Would they all last at least six pulls on the dyno? Keep in mind, this was not just a single-pull, top-horsepower competition. Each engine had to make three qualifying pulls from 3,000 to 7,000 rpm before making the three judged pulls required by the rules of the competition, so builders had to build their engines to last. The flat-tappet cam requirement and the 93-octane Rockett Brand fuel also forced the builders to be creative in coming up with a powerful combination. Each builder had their own ideas about how to make power-we had heads from Indy, Stage V, Mopar Performance, and even one engine with '68 casting factory Mopar heads. Induction ranged from single Dominator or Demon carburetion to dual Edelbrock carburetors, and even a tunnel-ram sporting dual 750 dominators.
Did the engines make power? You bet. Did we come up with a winner? Not yet.
Remember, the whole purpose of this competition was to show the readers what is available when it comes to the Hemi engine and to highlight each builder's techniques for making power. the retail cost of the parts in each engine will be divided into the horsepower/torque readings from the dyno, so the leader will not necessarily be the builder who made the most peak power, but the one who delivered the most bang for the buck. As of this issue's deadline, we haven't factored the cost portion of the contest, but we do have the dyno results and feel you'll be impressed. All of the engines survived the contest and made very respectable power, and while all were streetable engines, some were a little more exotic than others.
We'll highlight each engine in this article and give you the results of the dyno portion of our competition, but you'll have to stay tuned for the final results, which will be coming in a future issue. Also coming in future issues will be the details of each engine builder, their shop, and an in-depth analysis of each engine in our competition. Follow along, and we're certain you'll gain an in-depth knowledge of the potent engine called the Hemi.
Since this was the first year of the Royal Purple/Mopar Muscle engine challenge, we can't say it didn't go off without a hitch. Some of the parts that were required to set the Hemi engines up on the dyno didn't arrive in time, so we were really scrambling to make the competition happen on schedule. If it weren't for Mike Bond at Competition Cams, as well as Arrow Racing, Karbelt Speed and Custom, TCI, MSD, and Lakewood, we would have certainly been delayed. These guys all came through on short notice to provide us with the hardware necessary to get the job done. The engine builders themselves were also very accommodating, offering whatever parts or help they had to make things happen on schedule. We at Mopar Muscle would like to thank everyone involved for making the competition run as smoothly as it did, and on time. Superflow not only set up Comp's new 902 dyno in record time so the competition could happen, they sent customer service engineer John Seaman to Memphis to ensure things went smoothly. Along with the three drums of 93-octane go-juice, Rockett Brand sent vice president of engineering Tim Wusz to help with the competition and to answer any questions about the fuel we used for the testing. Several of the competitors consulted with these guys, and the exchange of information between everyone involved was incredible. It's amazing what you can learn when some of the best engine builders in the country consult with engineers from the likes of Comp, Superflow, and Rockett Fuels.
Enough about the setup, let's get to the meat of the competition. To ensure fairness, the order in which the competitors ran their engines was chosen randomly out of a hat. The procedure for all competitors was the same. The engine would be qualified by making three pulls from 3,000 to 7,000 rpm. We used an acceleration test of 300-rpm-per-second for all of the pulls. This is fairly slow acceleration for a dyno pull, but remember, these are supposed to be street motors. We are not just measuring power, we're ensuring the engines are legitimate street engines and have the endurance to back up the power they make. We didn't want any engines designed to make one killer pull on the dyno, just to explode the next time they started. During the qualifying session, each competitor had five minutes between pulls to make tuning changes or adjustments. If a competitor aborted a qualifying pull because of a problem, it had to be made up with a full pull, and no tuning was allowed during make-up pulls. Once the engine was qualified, the competitor had ten minutes to inspect the engine and make final adjustments before the scored pulls. In the scored portion of the competition, each engine was required to make three full pulls in a 20-minute time period. Tuning was allowed during the 20 minutes as long as all three pulls were completed in the allotted time. The pull used for scoring was the one with the best combined peak torque and peak horsepower. We're happy to say that all seven of the engines in the competition made their pulls in the allotted time with no major problems.
Larry and his team do some last minute tuning before their first judged pull of the compet
Hemis Only - Larry Shepard
Our first competitor in the dyno challenge was Larry Shepard of Hemis only, based in Akron, Ohio. In addition to his Hemi engine building expertise, Larry is an accomplished Top Fuel mechanic and clutch man. Needless to say, Larry knows his way around the Hemi engine. Larry's motor was one of only two sporting dual quads and the only one with Edelbrock carburetion. Larry also chose to use Mopar Performance cast-iron cylinder heads, stating a thermal advantage over aluminum pieces. Larry also claimed that the use of cryogenics, in addition to special metal coatings inside the engine, would give him a technological advantage.
Do tunnel-rams make power? Absolutely, this combination by Jeff Dickey of J.D.'s Engine an
Larry definitely wins our award for having the most patience of anyone in the competition. Since his motor was the first big motor on Comp's new dyno, it was run several times and made several partial pulls while John from Superflow calibrated the machine. We figure he needed an oil change before he even qualified, no question about endurance here. Next, an electrical problem caused the dyno computer to shut down fuel and ignition during the first qualifying pull at about 5,000 rpm, causing Larry's engine to misfire and diesel backwards for several seconds. The problem was repaired quickly, but everyone in the room cringed when the engine refired, fearing damage had been done. Luckily, the motor survived and, after minor timing adjustments, made all of its required pulls to set the pace with some impressive numbers. On his best pull, Larry made 701.8 hp and 639.6 lb-ft of torque (1341.4 combined score). these numbers are even more impressive considering that on teardown we found one of Larry's piston domes had been caved in during the qualifying runs due to the dyno malfunction. Larry's numbers certainly would have been better if his engine hadn't been damaged.
We can only guess how much power Larry Shepard could have made had his engine not been dam
J.D. Engine and Machine - Jeff Dickey
The only other engine in our competition sporting dual four-barrel induction happened to draw the second slot on the dyno. Everyone was eager to see if Jeff Dickey's entry would back up the impressive look of the tunnel-ram and dual Holley Dominator setup. Jeff has been building aggressive race motors in his Columbia, Missouri, shop for some time and has a reputation for finding power in his combinations. He and his team impressed us with their efficiency as they tuned their engine between each qualifying run, finding a little more power each time. You can definitely tell these guys are accustomed to working on a schedule. Our guess is they spend a lot of time at the track tuning between rounds. In addition to tunnel-ram induction, Jeff used Stage V cylinder heads and an aggressive cam profile in his combination. These guys didn't come to Memphis just to compete, they came to win.
Jeff Dickey (on right) and his team were very efficient, tuning their engine to more power
J.D.'s engine sounded strong during the dyno pulls and made impressive power each pull, but the engine's power fell dramatically above 6,700 rpm, and the sound of valve float was apparent. At least several of the valvesprings in this engine were weak or had given up. When their first judged pull put them solidly in contention, they had a dilemma: Make the two more pulls required and risk damaging the engine, or pull out of the competition. After some discussion among the team members, they decided to make the pulls and try to win the challenge. Making only minor adjustments between each pull, these guys made more and more power, finally netting a pull of 728.2 peak horsepower and 615.8 lb-ft of torque for a leading combined score of 1,344.0. Needless to say, these guys were glad they stayed in the competition. This engine certainly would have made more power if the valvesprings had let the engine pull all the way to 7,000 rpm. Power was rising rapidly during each pull, but peaked at 6,700, before falling dramatically due to valve float. J.D.'s only regret was that he didn't have time to change valvesprings between pulls so he could show us the real potential of his Hemi.
A blown freeze plug didn't leave Russ and Ken from Indy Cylinder Head much time for tuning
Indy Cylinder Head - Russ Flagle And Ken Lazzeri
When high performance is spoken of in Mopar circles, the name Indy Cylinder Head is certain to come up. Indy is a name synonymous with power in the world of Mopar engines. Indy has been manufacturing cylinder heads, blocks, and engine components from their Indianapolis, Indiana, shop for more than thirty years, and they are known for their cutting-edge technology. Several competitors other than Indy used Indy heads for their builds, and Indy intakes were atop most engines in the competition. Indy's Hemi included their own heads and intake, and utilized the longest stroke/smallest bore combination of the challenge. Everyone was eager to see how much power this single four-barrel, 500-inch Hemi would produce as it was bolted to Comp's dyno.
David Bruns and his crew help Mike Bond from Comp prepare their engine for installation on
When Indy's motor fired, it sounded strong, and all of its vital signs showed a healthy engine. During warm-up, the engine sounded smooth and powerful, but during the first qualifying pull, a freeze plug blew out dumping water into the dyno cell. This setback would cost the guys from Indy most of their tuning time as they repaired the freeze plug to make the remainder of their qualifying pulls. After a quick run through the valves, Indy's motor was ready for the judged portion of the competition. Only minor ignition timing changes were made during the judged pulls, and Indy netted a best pull of 649 hp and 600.8 lb-ft of torque, bringing their aggregate score to 1249.8. These numbers had everyone scratching their heads since we all expected Indy to be a contender. Upon the teardown of Indy's motor, the problem became apparent. They had been using their motor to experiment with some new camshaft technology, and a compatibility issue between the camshaft and lifter materials had caused all of the cam lobes to be scuffed badly, several to the point of a substantial loss of lobe lift. No doubt this engine would have made better numbers if the camshaft had lived through the test.
Ken and John from Superflow go over the numbers before Ken makes his tuning decisions. Tun
Mid America Racing Engines - David Bruns
If there is one thing we can say about David and Diane Bruns, it's these folks are a class act. David and Diane showed up with their motor at the Mopar Nationals and spent every minute of the event at our booth helping answer questions about their entry in the challenge, as well as the Hemi in general. They arrived early and stayed late each day helping us load and unload the engines from our trailer. Their help was much appreciated.
The Bruns' Mid America Racing Engines is located in Cedar, Minnesota, so we know that David and his crew have lots of time during the long, cold winters to develop powerful engine combinations. Dave told us that in the spirit of the contest he was using no special dyno tricks in his motor. He built this engine to thrive on the street. In fact, it ran so well on the dyno with no hint of detonation that we feel this engine would probably live a long life and make great power even on 89-or-lower octane fuel. To achieve this, David used Indy CNC ported heads and ended up with the lowest compression ratio of any of our competitors.
Mid America Racing Engines had definitely prepared for the competition. Their engine fired
When Mid America's engine fired on the dyno, we could tell immediately this engine's tune-up was already very close. The engine was crisp and responsive, and its vital signs were great. The first qualifying pull was smooth, and the engine made respectable power. This was probably the happiest engine we ran on the 93-octane fuel, exhibiting no signs of detonation. This engine sounded as though you could run it for hours at 6,000-plus rpm without a hint of a problem. David made only minor jet and timing changes to his motor during his pulls, and netted additional power and torque on each pull. David's best pull of 666 hp and 576.6 lb-ft. of torque for a tally of 1242.6 didn't necessarily put him at the top of the field in terms of peak horsepower or torque, but the torque and power curves of this motor were very broad. This engine was making over 530 lb-ft of tire-frying torque at 3,000 rpm! Who says a Hemi is strictly a top end motor. We feel this engine would be a great street motor: docile, powerful, dependable, and able to be fueled at any station with no worries.
The Lofgren's teamwork and willingness to think "outside the box" really impressed us. The
Lofgren Auto Specialties - Chuck Lofgren
Chuck Lofgren and his team from Washington, Iowa, showed up in Memphis ready to compete. These guys were taking this competition seriously, and their professionalism was apparent to all. "A well-oiled machine" is the best description of how these guys efficiently prepped and tuned their motor during the competition. Chuck Lofgren and his crew have been avid drag racers for years and are true competitors. While they have built engines for their own race cars for years, it is only recently that they have begun doing engine work for customers. The Lofgrens love to race, and while at the Mopar Nationals competed in the wheelstander class with their 9-second street-driven Barracuda. Their love for competition was also apparent during the challenge; these guys paid attention to every detail of their entry and even brought a weather station with them to aid their tuning. Due to Chuck's interpretation of the rules, the Lofgren entry was the smallest engine in the competition at some 485 ci and probably contained the heaviest pistons of any competitor. It also had '68-edition steel heads that one of their customers refused to run because of a crack. The heads were repaired, and the decision was made to combine the factory heads with an aggressive camshaft and single 1050-cfm carburetor atop an Indy single plane intake to make their power.
Even while preparing their engine for the dyno pulls, the Lofgren team thought of just about everything. They used high-temp silicone to seal the headers to the head and also sealed the slip-tubes of the headers, stating more accurate air/fuel ratio readings and cleaner air in the dyno cell as the reasons. During the initial warm-up, they set the float levels only and were ready to qualify. Several minutes were spent consulting with Tim Wusz about the Rockett Fuel's burn rate and oxygen content before jetting changes were made. Though the size of this motor and the use of factory cylinder heads had some wondering if these guys would be competitive, it was apparent during their first pull that the Lofgren's were not only competitive, but real contenders. Each pull on the dyno netted additional power and torque as the Lofgren team fine-tuned their combination. They even ran an air cleaner with a paper filter for their judged runs and amazingly showed a slight gain in power. As we said, these guys paid attention to everything, including the turbulent air in the dyno cell. This is one of the first engines we've known not to lose power on the dyno when running an air cleaner. We even checked to make sure they didn't soak the filter element in nitro for two days prior to the contest; they hadn't. Needless to say, we were impressed when this motor screamed up to 725.4 hp and 596.3 lb-ft of torque (combined score of 1321.7) and kept pulling strong. This was the only engine in the competition that made its peak horsepower right at 7,000 rpm and seemed to have more in it. We actually made an additional pull on this motor to 7,400 rpm after the scored portion of the dyno testing, at the Lofgren's request, and it made 731.5 hp at 7,200 rpm. Of course the final pull was not legal for the contest, but it did serve to impress all in attendance.
Muscle Motors - Mike Ware
Mike Ware of Muscle Motors in Lansing, Michigan, has long been known both as a Mopar enthusiast and for his ability to make horsepower. Muscle Motors is a busy shop, but they still found time to put together a solid motor for our competition. Mike and the guys did encounter the setback of wiping out the camshaft during their precompetition testing, so when their engine arrived it had a new camshaft installed that required break-in. While this scenario wasn't directly addressed in the rules, we consulted with the other competitors and allowed Mike to run his engine for a break-in cycle before qualifying. Mike was the only competitor to run a Mopar electronic distributor in his engine, which caused problems during initial start-up. The engine initially misfired considerably, causing all to wonder if it would make the pulls. In the spirit of competition, the Lofgren team loaned Mike their distributor and plug wires so that he could compete. This was just one example of how everyone pitched in to make the challenge fun and exciting. Nobody wanted to see any of the engines fail to compete, and everyone worked together to achieve this goal. Mike's motor utilized single Dominator induction, as well as Mopar Performance aluminum cylinder heads.
Though not his fault, things just weren't going right for Mike Ware of Muscle Motors. A ne
Noticing the turbulent air in the dyno cell, the Lofgren team chose to run an air cleaner
Mike takes out some pent-up aggression on the timing light. We're glad he chose to smash t
After fighting an ignition problem and breaking in the camshaft, the Muscle Motors entry was ready to compete. During the first pull, the engine sounded a little flat, but responded well to increasing the jet sizes in the carburetor. Working well under pressure, Mike increased the jets for each pull with a substantial gain in power every time. Mike and Muscle Motors would definitely win the "most improved" award if we had one for the competition. it wasn't Mike's day, however, when he bumped the dial on the back of the timing light during his judged pulls, inadvertently taking some twenty degrees of timing out of the motor. Luckily, Mike realized what had happened and corrected it for his final, and best, judged pull. Mike's best numbers were 666.5 hp and 585.7 lb-ft of torque for a combined score of 1252.2. As stated, this engine kept responding to increased jet size to the point that Mike had installed the largest jets anyone at the competition had available. Since the air/fuel ratio still showed lean, we're sure this engine had more in it. In fact, had Mike had more time to play with ignition timing, he certainly could have improved his numbers.
Speed-O-Motive's entry was competitive right out of the box with only minor ignition timin
Speed-O-Motive - August Cedarstrand
you won't find a nicer, and more fun-loving competitor than August Cedarstrand from Speed-O-Motive in West Covina, California. August has one of the most positive attitudes of anyone we've met and was genuinely excited about competing in our challenge. Speed-O-Motive has a reputation for supplying their customers with great power for the dollar combinations, so our expectations were high. The builders at Speed-O-Motive chose single Dominator-style carburetion (as did most of our competitors), and Stage V cylinder heads and valve gear. Instead of off-the-shelf CNC ported heads, Speed-O-Motive decided that hand massaging the units in-house could gain them some power. They also extensively utilized metal coatings, both as a thermal barrier and to reduce friction. This combination looks good on paper, but would it make power? The answer was a resounding yes.
When Speed-O-Motive's engine was bolted to the dyno, it fired immediately and sounded very healthy. August chose to begin his qualifying pulls as soon as the warm-up was completed and made only timing changes during the competition, stating they had optimized jetting during their testing in California. Evidently the techniques they utilized worked because the engine made impressive power on every pull. Minor timing changes made minimal differences in peak power and torque with a trade-off occurring. Adding timing would increase horsepower, but drop about the same amount of torque and vice-versa. This engine was ready to compete as delivered and made its optimal combined numbers on its first judged pull. How about 722.6 hp and 618.8 lb-ft of torque for a combined score of 1341.4! This was the best combined power total of the single four-barrel entries and put Speed-O-Motive in solid contention to score highly in the challenge.
A quick check of the plugs indicated the air/fuel ratio of this combination was nearly opt
That's the rundown on the competition so far. As we said, there is no clear winner yet. We'll be tallying the costs of the engines before the next issue, so stay tuned for the results. Remember that manifold vacuum will be factored as a bonus rating, so the builders who made the most peak power aren't necessarily going to come out on top. The idea of this competition is to provide a solid combination for the dollar amount spent, and to provide the readers an informative description of the Hemi engine and the engine builders who make the most out of this potent powerplant. Look for detailed inspections of each engine, the parts that went into them, and the builders who put them together in upcoming issues.
One thing we have learned for certain during this competition is, if you want a Hemi for your ride, you won't go wrong with any of the builders who participated in our challenge. We encourage you to contact any of these reputable shops to discuss options for your own Mopar. Special thanks to these builders for keeping the Hemi legend alive!