The year was 1964. Throughout the first part of the decade now renown for its automotive performance heritage, Ford, General Motors, and Chrysler had battled for supremacy in the racing world. Daytona, Bonneville, and drag strips throughout the nation had been the sites of these skirmishes, and each manufacturer had its moment in the sun. However, the start of 1964 was to be different, indeed.
Engineers at the Chrysler Corporation had pulled out all the stops and revived the hemispherical combustion chamber design that had been part of the luxury passenger car line-up in the '50s. Now displacing 426 cubic inches, the engine would no longer be considered a modified player used primarily in nitro dragster racing-the factory had reworked the technology around the existing RB-block combination as a flat-out competition unit, suitable for all forms of racing.
Here are the new lightweight valvetrain components for the Hemi(r) cylinder head. The rock
As the battle for the new season got underway, it was obvious that this was the secret weapon Dodge and Plymouth racers had needed to settle the score once and for all. With NASCAR's Petty family, the Summers Brothers efforts on the salt flats, and dozens of victories in every drag racing sanctioning body, the legend of the Hemi was soon firmly established. Only changes to the rules kept it from total dominance of these series.
The Legend Lives On
Despite 35 years of history, little has tainted the reputation of a well-tuned 426 "elephant" motor. However, since all racing series and products live in a state of flux, in some ways the technology that dominated that '60s is no longer viable in the 21st century. Though the design continues to be the dominant factor in nitromethane-burning vehicles, it is now too big displacement-wise for NASCAR and is not a factor in Pro Stock racing, either. There are a number of reasons for that truth.
The shape of the Hemi piston and combustion chamber may work very well in applications under 8,000 rpm, but above that speed, a number of critical problems can occur.
First of all, the weight of the reciprocating parts themselves. To build a true hemispherical combustion chamber requires a piston forging that will automatically weigh more than a similar construction wedge-style piston simply because of the shape.
Another view of the rocker arms and stands. Since the aftermarket does a superb job in tur
What's more, that piston's movement will need to be timed properly to do two almost opposing tasks-fill the chamber to build significant compression while avoiding problems with valves hitting the piston's face. At lower rpm levels, valve timing is not as critical, but in the world of Pro Stock racing, there is no room for error. Indeed, the best engine designs are on such a ragged edge that valve timing is set so the valves will actually barely touch the piston on the intake stroke. The design inherently makes big compression incompatible with high-valve lifts.
Then there is the problem with the valvetrain itself. Those long rocker arms and shafts might have made the assembly of the engine simpler, but they are actually modified versions of the technology originally developed in the '50s. At high rpm, there is a whole lot of flexing and bending of these parts. Also, they are not only heavy, but they contain some "unique" geometry (pushrod angles, etc.) where, again, high rpm efficiency suffers.
The Next Generation
So, it was within this environment that the design for the new-generation Hemi began. The photos you see here were taken at the Nickens Brothers Racing Engines shop near Houston soon after the initial pulls on their first Hemi motor were done. David Nickens, who is involved not only in this design but a small-block Pro Stock Truck program as well, graciously allowed Mopar Muscle to see some of the hardware used in making the new motor. In the captions, you will get a first look at the parts that are almost assured to put Chrysler's Pro Stock program back on the map.
This is the partly-machined Hemi cylinder head casting as seen from the exhaust side. As y
Main caps are created from high-tensile aluminum alloy to keep weight down and are cross-b
You are looking at the bottom end of the second-ever new Hemi motor put together at the Ni
Perhaps one of the most telling items of the amount of thought that went into the motor is
Created from a steel forging by Steve Lowe at LSM, this view shows how far the lifter posi
Whatever It Takes
David Nickens has lived his life in the drag racing fast lane for over twenty years now. The winner of 30 national events in the last 15 seasons, David and his brother Robert's racing operations have been noted for go-for-the-throat engine development program-a notoriety that has made many of his competitors his customers. Now working on engine development programs for Mopar in both Pro Stock and Pro Stock Truck, few doubt that Nickens Brothers Racing Engines will soon be posting major victories in these Professional categories.
With a brand-new 12,000-square foot shop now being completed in Conroe, Texas, and two dozen full-time employees working in various aspects of the business and racing teams, Nickens will accept nothing less than Championship prizes for his effort. During the creation of this first look at the new Hemi engine, David sat down with us to give his insights on drag racing, the new parts, the new Hemis, and his career.
Q: What got you involved in drag racing
A: I started when I was in high school, taking auto mechanics courses and being enthused about racing. After racing locally, I built a Modified-class car and went to the Winternationals in Pomona in 1979. I didn't win, but I was close enough that I was hooked. I won my first national event in 1985, and I raced for Castrol for 10 or 11 years. During that time, we also developed our shop and began building our own engines because we found we couldn't get the power we needed buying them from somebody else. It just kind of evolved from there. We now build engines for a lot of customers. Eight of them have won championships, including myself in 1991, and my son Bo in 1996. I've won 30 national events, Bo has won eight, and my nephew Buddy, who is Robert's son, has won seven. When I moved into the truck ranks, I was able to win the first race they held here in Houston. It's been a wonderful sport for us and a wonderful sport to us over the years.
Getting hooked up with Mopar Performance two years ago let us develop the new small-block, and we are now refining the latest version of the Magnum that has evolved from that. It's going to be a neat, neat engine, and once we get it done, I can almost guarantee it will be able to win the Championship. Fortunately, we were also able to get the Pro Stock car program as well. It seems like we have been creating a new motor for that every year, with the Wedge last season and now the Hemi. The best thing about the Hemi is that we believe it can become a top contender right away due to the design work built into it.
Most of our work is now dedicated to Mopar programs in the Pro Stock and Pro Stock Truck ranks; we still do work for some customers, but our focus is on those programs. There is no replacement for hard work. The guy who works the hardest and the smartest will be the one who wins, and that will never change. Now that we have the funding to do that, I want to go out and build engines for this team to win championships with.
Q: Do you miss driving?
A: Not really. Scott (Geoffrion) and Darrell (Alderman) are incredible drivers, they do a great job, and I am satisfied to put that part of the jobs into their hands. I enjoy the development of the engines, I enjoy being at the race track, and working on making the cars run, so I am happy to watch them go out and make those improvements work. Together with Bo in our truck effort, I feel we have the best talent out there working with our stuff.
This is the Sonny Bryant crankshaft that is used in the new Hemi. Cross-drilled and with a
Here is an as-sold view of the new Hemi casting's combustion chamber. Purists will note th
Here is the front of the block with a motor plate, timing outfit, and crank trigger igniti
Here is the end of the Hemi block showing the crank and cam installed. The plate on the ba
This view of the new Hemi lifter valley gives you an idea of just how much change has occu
The belt seen here drives the dry-sump oiling system. The trigger light for the crank trig
These are the completed heads on the first Hemi motor from Nickens Brothers Racing Engines
Q: Tell us about the new Hemi motor. How did that get underway?
A: We first saw the pieces that would be part of the Hemi right towards the end of last year, and we got our first engine in December. We've really been tight trying to get one of these things together to run at the Winternationals. It's been an uphill battle to do that, but we have made some dyno pulls and are pleased with what the engine has shown us to this point. Honestly, I would guess we are about three months away from where we need to be to make the engine competitive; we are refining parts all the time and that just takes time. Hopefully, once the engine is in the car, that learning curve will be faster and we'll be able to win some races. The plan right now is for Darrell's car to get the first engine.
This Stef's oil pan is used in conjunction with the dry sump. On the opposite side of the
Q: What is the toughest part of developing an engine?
A: As an engine builder, the most frustrating thing at this point is just the time it takes to develop and get things manufactured. Though we are used to being able to build everything ourselves here, sometimes it takes a while to simply build up the quantity of parts needed to make the changes you want on the dyno. For example, you have to have camshaft cores made, and then you have to figure what redesign you want on the lobes and it's a constant state of waiting to try the next idea. Fortunately, Team Mopar is dedicated to doing whatever it takes to making this program work. Normally, it would take three or four months to get a change made to a block or a head or tooling, and these guys are doing it in a third of that time. Again, since we are only in the first phase of making those changes, we are a few months away from being where we need to be, but it will come real fast. I'll tell you, we've got a great product to work with.
Q: Let's talk about the design of the cylinder head compared to the original Hemi configuration.
A: Certainly, the Hemi was a dominant product when it was built, but it was surpassed by some of the new technology. Being able to create a lighter reciprocating assembly has a lot to do with that, and a piston with a true hemispherical dome just adds so much weight. Today's engines also need to have a positive valvetrain, one that is stable in the upper ranges of the rpm scale. Those are the two major places we have made changes on this engine and I think we will see in a short period of time that those changes will pay out big dividends.
Q: The lifter valley is unique. Let's talk a little about that.
A: The engine was designed for nothing but the Pro Stock application, so when we developed that, we didn't have to leave anything on the 'real estate' of this engine unchanged; we designed it to function in that environment. We put the stuff right where we wanted it the first time and hopefully we won't have to refine anything there and we'll be able to focus on other areas. The guys with the GM program have had to move that stuff themselves, so we are fortunate to have it cast that way.
Q: What about some of the other innovations seen in the new Hemi?
A: Well, I see the valvetrain assembly and realignment of the runners beneath the carburetors both as big pluses. The valve location itself is a major change. All of these things that we have designed into this engine compared to engines from any manufacturer in the past are to bring about horsepower gains in those areas. We look at this engine as being the state-of the-art in the sport, period. It is designed to make horsepower at the upper ends of the rpm range, where big displacements have suffered in the past. Making power above 9,000 rpm will make huge improvements on the racetrack.
Here is how the distributor mounts on a vertical plane above the timing equipment. A new d
This image shows the mounting of the individual rocker stands and arms.
Shown here with the complete reciprocating assembly, the lightweight connecting rods used
As seen on the right piston in this photo, the new Hemi still retains a dome shape to the
The Hemi on the dyno! These photos show the guys at Nickens Brothers getting ready for ano
Here is the first intake manifold created for the new Hemi engine. Though others have sinc
The intake ports seen here show the cylindrical design that was settled upon for increased
There are so many factors that make this a great engine. For example, it looks like it is going to be easier on valvetrain parts. To this point, we are so early into the development of this thing that we are the only ones to actually take one of these things down the racetrack. We need to run it in competition with other cars in the racing environment to see just where we actually stand, with identical conditions and track prep.
Mopar is using this engine as a platform to build a true identity, so we want people to think Hemi when they see it, and in doing that, we want them to realize that this is what it is going to take to be competitive.
Q: Let's look at the new Magnum small-block engine. What have you done with that?
A: The main changes are to the runner configuration and the valve angles, and it is now a canted-valve style engine. We've developed a short deck block instead of the old blocks we had last year. We added some material in places where we think it will benefit us, but the big gain is in the cylinder heads. The new Magnum is just an incredible piece of engineering. Though they were designed by two completely different groups of people, the new Magnum and new Hemi heads are almost identical. We are seeing a clear advance in cylinder head design itself with these parts, in both airflow and functional use. We have not taken a head that was made for a passenger car and adapted that to racing; we have a head that was made for this kind of racing and it will be a big advantage over other combinations.
This view of the underside of an as-cast Hemi head show the positioning of the intake and
Q: Is there anything else in auto racing equivalent to this?
A: I don't think so. This is a whole new design that will revolutionize the truck program.
Splayed-valve engines have the exhaust valve moved and canted on one angle and the intake valve moved and canted at a different angle, moving the valve away from the cylinder wall and removing that restriction on airflow. We feel the changes we made here will take that design to the next level.
Q: Are there any other applications for the new parts beyond drag racing?
A: We have worked fairly close with the NASCAR teams since Dodge is going NASCAR racing next year, and the development we've done on the Magnum block will certainly carry over there. Due to the rules, the [Hemi] head itself might not, but the intake port design will probably find some use there as well. We like to think that being a family with the other teams at Dodge allows us all to work at being the best we can be, and so we trade knowledge back and forth.
Q: What about other racers? Does the factory have Larry Morgan and David Nickens working together on the project?
A: Well, it's not demanded of us, but Larry and I are real good friends and talk almost every day. Anything he needs or wants, I will help him as much as I can, and I know he would do the same. We've known each other since the 1970s, and he was the one who got me on the Castrol team, so I owe him a great deal of gratitude for that.
This view of the underside of an as-cast Hemi head show the positioning of the intake and
Here is the Hemi we used in the photo session after being taken apart following dyno work.
Here are two more peripheral parts that are used to make the new Hemi work. At the right i
This view shows the front and rear covers and timing system, all built by Jesel for the ne
This image shows what the head and valve cover combination look like. Obviously, there wil
Hooker Headers was responsible for welding up these pipes for Nickens Brothers. As is comm
These valve covers leave no doubt in the viewers' minds as to the manufacturer or engine d
I gladly became the first member of the press to physically work on the new Hemi motor dur
Dodge Magnum Pro Stock Truck engine
Q: What drives David Nickens in these programs. Where do you get your satisfaction?
A: Certainly, winning is important and having that competitive edge over the rest of the field is satisfying. Making my team the very best it can be and bringing out the best qualities in the people who work with us, giving 100 percent to this effort, that is the best feeling, because the winning will happen. There's no price tag you can put on knowing that you beat everyone else, the very best people in your sport or class, when you are in that winner's circle on Sunday evening. You want to work so much harder when you are winning; you want to maintain your advantage. Sometimes, work can be consuming because you are willing to make those sacrifices to win. You will spend as many hours as you physically can working on your racing program. I want to work. For me a good day is working all day. That can be working at the track to find things out or working here in the shop, whatever it takes to make it perform better.
I think we are looking for big things out of these engines. I would like to say you will see that at the first race of the season, but that is not realistic. A couple of months down the line is when the results will begin to show. That is a tribute to the guys in the shop here, who have worked incredibly hard to get these engines where they are already, and I think you will see both of them move right to the front of the pack.
Finally, getting the (Dodge) Boys up and running has been a great experience, too. Watching Bo and Buddy do so well with their cars, watching them win, that drives me to come back here and develop more horsepower for them, even if it takes 24 hours a day.
|Dodge Motorsports/Team Mopar |
Pro Stock Hemi® Specifications
|Type: ||Dodge Hemi(r) V8 |
|Displacement: ||500ci |
|Bore: ||4.675-inches |
|Stroke: ||3.675-inches |
|Horsepower: ||1275 at 8,700 rpm |
|Torque: ||790 Ib.-ft. at 7,600 rpm |
|Redline: ||9500 rpm |
|Compression Ratio: ||15.1:1 |
|Cylinder Block: ||Cast iron V8, full skirt bottom end with cross-bolted mains. 4.90-inch bore centers. Mopar Performance Parts #P4876887 |
|Cylinder Heads: ||Aluminum Hemi(r)-style, Two valves per cylinder. Mopar Performance Parts #P4876883 |
|Induction System: ||Dual Holley 1150 cfm Dominator four-barrel carburetors, fabricated aluminum sheet metal intake manifold |
|Camshaft: ||Steel billet roller |
|Connecting Rods: ||Aluminum |
|Crankshaft: ||Steel billet |
|Cam Drive: ||Jesel belt drive |
|Valvetrain: ||Titanium valves, valve springs and retainers; Jesel aluminum roller rocker arms |
|Ignition System: ||MSD capacitive discharge |
|Spark Plugs: ||Bosch |
|Lubrication System: ||Dry sump with 9 qts. Mobil 1 Tri-Synthetic, 5-stage external oil pump |
|Oil Filter: ||High capacity free-flow Mopar Performance Parts #P4529190 |
|Fuel: ||VP C25 118 octane |