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Performance - Working The Mopar Magic
It doesn’t take much more than a casual observer to tell that the performance market is alive and well. Most magazines you pick up have numerous articles on performance engine build-ups for Chevrolet and even some for Fords. Notably absent from these magazines for the past decade or two, however, have been stories on building Mopar engines.
This is not all that unexplainable when you consider that Chrysler’s performance engine technology has wallowed in the 1960s for nearly 30 years. Chrysler dropped out of the performance business for the most part when it ended its pony car youth market in the ’70s. However, there are signs that the company is making a larger commitment to the performance market today.
Chrysler has found the youth performance market again with its pickup trucks, and there are rumors of a new four-seat, rear-wheel-drive, V8 performance car. The performance arm of Chrysler – Mopar Performance – has started to list some new heads, blocks, intakes, etc. in its performance catalog, as they are long out of production on Hemi and wedge V8s.
But as any machine shop or engine rebuilder knows, the OEM cannot do it all. History has shown, as in the case with General Motors and Ford, many of the OEM’s performance and powertrain development strides have been made in the shops of independent builders and developers.
One such machine shop that specializes in grassroots Mopar performance engine development is Hughes Engines, Inc., of Washington, IL. Hughes Engines has been in business since 1969, starting out as a shop that specialized in NHRA stock and super stock cylinder heads. As the performance market dwindled in the late ’70s and ’80s, Hughes moved into the general custom engine rebuilding market, along with offering aluminum cylinder head rebuilding services and components.
About eight years ago this five-man shop decided that the way to best expand its growth was to become a specialist. No more "whatever comes in the door" type of jobs for them. Hughes now defines its primary market as a "niche within a niche." It has become a strictly Chrysler wedge specialist for restoration, cruiser, street, strip and oval track applications. Hughes concentrates on engines using pump gas or those with specialized restrictions, such as the oval track restricted engines.
Even though Hughes is a Mopar niche specialist, it doesn’t court whatever engine work comes in the door Mopar-wise, either. If you need a Hemi or a mega-inch drag race engine, Hughes will refer you to someone else. In a market where many shops seem to be struggling just to pay for the overhead, Hughes has a six-week backlog for complete engines.
The Mopar market is "fun" because much of the technology and products Hughes brings to its customers has already been developed and proven, yet has not been extended to this limited Chrysler performance market.
One of these products is Hughes’ line of redeveloped cam lobes that it calls the "Real Chrysler" camshafts. These proprietary-grind camshafts are manufactured strictly for Hughes. The cam profile is based on the larger lifter diameter that Chrysler engines use. The large diameter allows a faster rate of lift which translates into a wider power band and more power. Since the majority (about 95%) of the performance cam market is GM, it is cost prohibitive for the major cam grinders to provide the cams that Hughes is able to offer its customers.
Another area of specialization and expertise for Hughes is cylinder head work. The so-called pocket-ported or ported-and-polished designations have gone the way of bell bottom trousers. They’re currently offering at least a half-dozen specialized porting levels for the garden variety cast iron heads that were OEM since the mid ’60s (bell bottoms again). The situation with Mopar head porting is similar to the situation with Chrysler cams, i.e., if you have a flow bench and your shop wants to make easy money, you port Chevys.
The biggest problem with all the Mopar OEM iron heads is that the air flow virtually stops at about .350" lift; by .450" you can pull the valve out of the picture and won’t be able to achieve any more flow. This fact alone has fostered the belief that Mopars don’t like or need high lift cams. What some people may not realize, however, is that the fast rate-of-lift will also benefit the stock heads. If the flow limitation in the heads can be eliminated, there is a lot of potential to be gained.
Hughes has ported, flowed, machined and ruined pallets of junkyard heads before coming up with three levels of what it calls its PRO-POCKET heads. As its ads say, "One head is not best for all engines."
The three PRO-POCKET levels are based on five criteria:
1) The use of the vehicle;
2) The extent of other engine modifications;
3) The chassis, such as weight, gearing, etc.;
4) The goal or end result expected; and
5) The fuel to be used.
Most racers only look at air flow numbers when choosing a head, believing that biggest is best, or that bigger is always better. However, when it comes to performance, this can be very misleading because the flow volume may be less important than the velocity of the port. It is at least always equal to it.
Velocity numbers can also be confusing. You can use the port volume as a good reference point. For example, if the air flow of two heads is very close to one another, the one with the smaller port volume will have a better power band and, consequently, is the better head. Some of the GM racing heads are listed by port volume, not air flow. Although this is a new concept for Mopar racers to adjust to, they are catching on quickly.
Hughes lists its heads by both air flow and port volume numbers. It is constantly working to reduce port volumes without losing air flow. A Stage I level of porting is limited to a few specific areas of the port, so as not to increase the volume any more than necessary to get the results desired. This keeps the port velocity high for a wide power band while maintaining the low-end throttle response for the street enthusiast.
Its Stage II level cylinder head is for street strip, bracket racing and oval track engines. Hughes has even divided up the available Mopar castings by port volumes to further customize the heads at this level. Generally, the port volumes are larger for higher rpm use and the emphasis is on horsepower as opposed to the Stage I’s driveability slant. Smaller port heads in this group work best on heavy cars or those for short oval tracks.
Hughes’ Stage III head has the maximum port volumes and larger valves for maximum effort drag racing on large engines and/or very light cars. Hughes also has specialized porting for RV and towing applications.
The limited and restricted oval track engines have unique needs, such as specialized valves, valve jobs, cams, modified "stock" intakes and stealth heads for those whose conscience will allow them to use them. Hughes stands ready to help those individuals, too.
Some of these limited or restricted classes require flat top pistons. Hughes has some extremely lightweight crank spinning assemblies with bobweights under 1675 grams. This might not seem light to some racers, but it is more than 450 grams per bob lighter than the average 360 Mopar bob. And this is with 6.125" steel rods and a "stock" iron crankshaft.
Chrysler wedge engines have long suffered with their version of "early thinking" emission combustion chambers in the form of a semi-open, nonquench design. Hughes advocates the use of Silvolite, Keith Black pistons with their quench domes, citing that they help the more common open chamber Chrysler heads to operate like closed chambers. Properly built, Hughes feels that the pistons will allow more cylinder pressure, especially when using pump gas. The end result is more overall power compared to other piston designs it has tried.
At the big end of its catalog offering is a 440 cid engine stroked one-half inch. At 505 cid it develops 590 horsepower using a hydraulic cam and pump gas.
Even the newer Magnum truck engines have room for improvements. Hughes offers modified throttle bodies, intake manifolds, cams, two levels of ported heads and roller rocker conversions. The problem with this engine’s high performance development is that the engine management end of this market is not nearly as sophisticated as that of the much more advanced 5.0L Ford high performance market. Once again, a problem for the smaller niche market vehicles.
But the employees at Hughes have found a home – one which has allowed them to enjoy a small but profitable niche market. A niche where the customer demands, appreciates and is willing to pay for the products and expertise that Hughes is able to provide.
Next stop? The Internet.