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Brodix Cylinder Heads, Engine Block & Intake Manifold Insight - CHP Insider

Jeff Brotherton of Brodix Schools Us in the Art of Cylinder Head, Block, and Intake Manifold Design & Manufacturing

Stephen Kim Feb 1, 2009
0902chp_01_z Brodix_cylinder_heads_engine_block_intake_manifold_insight Jeff_brotherton_of_brodix 2/13

If you want the cheapest deal in town, look elsewhere. Brodix isn't shy about the fact that its products aren't the least expensive on the market. The company is confident that its cutting-edge R&D capabilities and state-of-the-art manufacturing facility yield the highest-quality cylinder heads, intake manifolds, and aluminum blocks in the industry. And the last time we checked, Brodix isn't having any problems selling parts. For the better part of four decades, Brodix has powered race-winning machines in everything from NHRA Pro Stock to World of Outlaws sprint cars to grassroots-level drag, circle track, late-model dirt, and tractor-pull racing. The company developed its first aftermarket cylinder head in 1971, and with one of the most advanced in-house foundries in the business, it has been refining its manufacturing techniques ever since. Intrigued at what exactly the manufacturing involves, we picked Jeff Brotherton's brain to learn how things like testing, tooling, casting, heat treating, machining, racing, and even networking all come together. It's a fascinating and enlightening science, to say the least. So, gentlemen, may we have your undivided attention?

0902chp_02_z Brodix_cylinder_heads_engine_block_intake_manifold_insight Cnc_setup 3/13

CNC Setup
People throw around the term "CNC-ported" but don't often think about what the process involves. The effort put into setting up a CNC machine has a dramatic impact on the quality and repeatability of replicating a port accurately. "A human has to shape the first set of heads by hand, and CNC porting is only as good as the programmer setting up the machine," explains Brotherton. "It takes even a good programmer three to four sets of test heads to get a program completely dialed in. After that, quality is based largely on how fast you want to run the machine. Running the machine slower allows for tighter stopovers and better flow but also reduces productivity and your profit margin. On the other hand, you can make a CNC machine run so fast that it will actually bend the tool in addition to reducing the accuracy of the port. It's all a compromise."

0902chp_03_z Brodix_cylinder_heads_engine_block_intake_manifold_insight Virgin_aluminum 4/13

Virgin Aluminum
It's true that big flow numbers are key to making serious power, but the durability of the head casting itself is paramount in making that power reliably. Brodix uses A-356 virgin aluminum extensively in its castings, which consist of manganese, nickel, strontium, and copper "It's a lot like baking a cake, and we've perfected the recipe over the last 30-plus years," Brotherton explains. "The more money you pay, the purer the base metals and ingredients. By strictly utilizing virgin ingots, the result is a casting that is more forgiving and holds up better to cracking and repairs. The formula needs to be modified depending on the application, and sometimes you'll run into a bad batch of ingots that need to be replaced."

0902chp_04_z Brodix_cylinder_heads_engine_block_intake_manifold_insight Company_roots 5/13

Company Roots
"Brodix has been in the aftermarket cylinder head business for close to 40 years, and the company literally came together as a marriage. My dad, J.V. Brotherton, was an avid hot rodder, and my mother's dad, Francis Dix, was in the foundry business. By combining J.V.'s fascination with cylinder heads and Francis' expertise in high-strength alloys, Brodix developed a clean-sheet aluminum Hemi head in 1971. With Mopar's reintroduction of its own Hemi head cutting into Brodix's sales, we regrouped and developed an all-new small-block Chevy cylinder head in 1973. Through the years, Brodix has been involved in just about every form of amateur and professional competition, including NHRA Pro Stock and World of Outlaws Sprint Car racing. Consequently, we've earned a reputation for our ability to produce high-strength, close-tolerance castings with excellent power potential. Our 15-degree SBC casting, launched in 1987, has become one of the most successful heads in sprint car racing. Our company expanded beyond cylinder heads with a complete line of intake manifolds and the introduction of an aluminum SBC block in 1996. That was followed up with a new BBC aluminum block in 2003, which went on to win in NHRA Super Comp at the '04 U.S. Nationals. Today, Brodix has a diverse product line for everything from street/strip components to full-on Pro Stock race hardware."

0902chp_05_z Brodix_cylinder_heads_engine_block_intake_manifold_insight Cylinder_port_shape 6/13

Port Shape
The constant struggle to achieve the ideal balance between airflow and cross-sectional area is influenced heavily by port shape, and Brodix opts for oval ports whenever possible. "Almost every head we build is an oval-port design, as there are really no performance benefits of a rectangle port," says Brotherton. "An oval port maintains a uniform shape throughout the head from the port entrance all the way to the bowl. This keeps airflow constant, which improves velocity. Plus, unlike a rectangle port, oval ports have no corners for fuel to get stuck in."

0902chp_06_z Brodix_cylinder_heads_engine_block_intake_manifold_insight 3d_design_of_cylinder_heads 7/13

"The goal at Brodix has never been to offer the cheapest products on the market, and our R&D efforts clearly illustrate why this is the case. Our niche is manufacturing the highest-quality castings around, a process that is all done in-house. Every new part starts as an idea, and then we must determine what price range and market we want to enter. Sometimes we can modify an existing cylinder head to meet our goals, but we often have to start from the ground up. A good 70 percent of our R&D work is done the 'ol old-fashioned way. You can do all the computer designing you want, but until you test a set of heads on the flow bench, on the dyno, at the track, and on the street, you have no idea how it will affect the acceleration and throttle-response of a motor. Once the tooling and CNC programs are finalized, we can move into manufacturing mode. Designing a new head from the ground up takes close to a year from start to finish."

0902chp_07_z Brodix_cylinder_heads_engine_block_intake_manifold_insight Repairing_cylinder_heads 8/13

Repair Facility
Brodix has what is arguably the best cylinder head repair service in the industry. Regardless of the type of cylinder heads that are in need of repair, Brodix offers the service to everybody. According to Brotherton, there's really no such thing as a head that can't be fixed. "Nine times out of 10, whether you've hit water while porting a casting too thin or blown a chunk of metal out of the combustion chamber, we can fix whatever you send us, but the question is whether or not it's cost-effective," he explains. "All you have to do is send us your heads and include a note in the box of what you'd like done to them. We'll then survey the damage and give you a price quote on what it will take to repair them. How good they turn out has a lot to do with the quality of the castings. Good castings can be heat-treated back to like-new condition, but factory heads have a tendency to get soft. Also keep in mind that all epoxy will be lost during the welding and heat treating."

Racing Exploits
It's been said that racing improves the breed, and Brodix has been involved in on-track competition from day one. In addition to the high-profile action in NHRA Pro Stock and World of Outlaws sprint cars, the company is deeply involved in grassroots competition such as circle track, late-model dirt car, Outlaw 10.5, power boat, and tractor-pull racing. That translates into a seamless transition of racing technology into Brodix's consumer product line. "The world is just now starting to hear about wet flow technology in cylinder heads, but we've been using it in our R&D efforts since 1986," Brotherton says. "We just kept it under wraps for a couple decades because of the advantage it gave us. The current direction of our company is to continue involvement in all forms of racing while developing more products for the street and show-car markets."

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Easy 18-Degree Conversion
Everyone knows that 18-degree small-block Chevy heads are an all-around superior design to a conventional 23-degree head, but most shy away from them due to the costly valvetrain components they require. Brodix feels your pain and has solved the problem with its -18X castings, which are compatible with 23-degree valvetrain hardware. "These heads still require an 18-degree-specific intake manifold and pistons, but they take advantage of the improved architecture without the need for offset lifters or pushrods," explains Brotherton. "It's a bit of a Catch-22, since we don't have as much flexibility with the intake port, but we were still able to improve upon the three most important aspects of port design, which are the valve job, short turn radius, and port entrance. The 18-degree design not only affords a flatter angle but enables using larger valves as well. As cast, these heads flow over 320 cfm out of the box and are good for at least 50 hp over a 23-degree casting."

0902chp_09_z Brodix_cylinder_heads_engine_block_intake_manifold_insight Aluminum_engine_blocks 10/13

Aluminum Blocks
"Unlike cylinder heads, where the primary focus is making power, engine block design is more about strength and accuracy. In addition to providing stability in the cylinder sleeves and mains, the tolerances must be very precise. This encompasses where the cam is positioned in relation to the crank, and the location and roundness of the cylinder walls. Other features of our blocks include a reinforced lifter valley, splayed billet mains, widened pan rails, a raised cam location, and revised oil passages. Our aluminum big-block can be ordered in deck heights up to 10.700 inches and sleeves that can be bored to 4.600 inches, good for 665 ci. Our aluminum small-block can be had as tall as 9.500 inches with a 4.125-inch bore for a total of 454 ci. Compared to an iron block, our aluminum big- and small-blocks are 130 and 90 pounds lighter, respectively."

0902chp_10_z Brodix_cylinder_heads_engine_block_intake_manifold_insight Intake_manifold 11/13

Out-Of-The-Box Performance
Whether it's cylinder heads or intake manifolds, Brodix is well known for outstanding out-of-the-box performance. Brotherton says that it's not just a coincidence that Brodix casts all its products in-house as well. "You can design a cylinder head or intake that performs well, but it doesn't mean much if you can't accurately replicate that design through the casting process. We have what we feel is one of best foundries in the business. The luxury of casting our products in-house allows us to very closely monitor the accuracy of the tooling and the logistics in the foundry from start to finish. That means we can continually make tweaks in the pattern shop to ensure that our castings are as close to the original cylinder head and intake manifold designs as possible."

0902chp_11_z Brodix_cylinder_heads_engine_block_intake_manifold_insight Inhouse_foundry 12/13

In-House Foundry
Although quality control is determined by a plethora of variables, Brotherton says that having a state-of-the-art, in-house foundry is critical. Primitive foundries can sometimes get the job done, but consistency is a gamble at best. "If you rely on an outsourced foundry, then instead of being able to control how the foundry operates, you're at their mercy," Brotherton explains. "If we have a problem with a batch of heads, I can stop the foundry immediately after just 10 heads into the run by walking over to the appropriate section of our facility. Hiring an outside foundry not only eliminates that kind of flexibility but forces you to buy heads in batches of 400-500 to get a good price, so if you have issue with porosity or inconsistency, you're probably going to try to weld those heads up for repair instead of throwing them away."

Intake Manifolds
Since cylinder heads and intake manifolds work in concert as part of the induction package, Brodix manufacturers its own line of intakes to maximize the performance of its heads. "Building our own intakes in-house enables us to design a cylinder head without making compromises based on what manifolds may or may not be on the market for it," says Brotherton. "With all of our R&D data at our disposal, we know right off the bat which manifolds will work well with a new head design, which we feel gives us a leg up on the competition. In the event that a new cylinder head features revised architecture-such as raised runners or altered valve angles-we can design a new manifold for it from the ground up. That way we don't have to rely on manifolds from different manufacturers that are already on the market, or force our customers to build expensive sheetmetal one-offs."

Oval-Port Mouse Heads
If oval ports work so well on Rat motors, why not try them on a small-block? Brodix couldn't find any good reasons not to, so the company is hard at work on a raised-runner 210cc oval-port small-block head. "Despite the fact that these heads will retain the conventional 23-degree architecture, they will flow 335 cfm in CNC-ported trim," says Brotherton. "People like using standard valvetrain hardware, and these heads will be compatible with conventional 23-degree lifters, rockers, intake manifolds, and valve covers."

Heat Treating
Considering that raw cylinder heads straight from the foundry are too soft to use on a motor, heat treating is imperative to durability. "After the heads are unloaded from the unmolding station, they're not quite ready to bolt on yet," Brotherton explains. "We can't get too specific because our heat treating process is proprietary, but a simple explanation is that we heat the heads at high temperature for an undisclosed duration of time. After the heads are removed from the oven, we cool them with water, let them air-dry, and then put them back into the oven at a lower temperature for a shorter time. The process is very time-consuming, but it significantly strengthens the casting."

0902chp_12_z Brodix_cylinder_heads_engine_block_intake_manifold_insight Brodix_cylinder_head 13/13

Pro Partnerships
"Brodix has teamed up with some of the best engine builders in the country to bring our customers race-proven technology at an affordable price. We have some pretty good cylinder head guys at our shop, but combining the skills of championship-winning engine builders like Sonny Leonard with our manufacturing capabilities results in some of the best cylinder heads on the market. For instance, our PB2005 big-block Chevy race head is a 14.5-degree casting that was designed by Leonard and flows 560 cfm. Sonny came to us and asked if we'd be interested in reproducing his design in our facility to offer to our customers, and the rest is history. We're old-school people, and honesty and a handshake mean a lot to us. Guys like Sonny trust us, so if they send us something they came up with that makes power, and we're able to replicate their designs accurately, it saves us both time and money and ultimately gives the customer a better product."



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