Trick Flow Cylinder Head Insight - CHP Insider
Al Noe Of Trick Flow Reveals What It Takes To Design And Manufacture Topnotch Cylinder Heads And How To Choose The right Set For Your Combination
From the October, 2009 issue of Chevy High Performance
By Stephen Kim
Photography by Courtesy Of The Manufacturer
Whether you want to admit it or not, more than a few Bow Tie racers have lined up against 5-point-slow Mustangs only to discover that they-on rare occasion-aren't actually all that slow. Chances are that in order to get their tiny 302s to run with the bigger 350ci competition, they probably had a set of Trick Flow heads under the hood. Although it entered the marketplace serving the needs of the dark side (where it earned a reputation for phenomenal out-of-the-box performance), Trick Flow has since brought the same venerable formula of budget-oriented horsepower to the Chevy faithful. Today the company offers a plethora of cylinder heads for big-block Chevys and all four generations of small-blocks. From raised-runner 23-degree small-block heads to oval- and rectangle-port big-block heads to monstrous 265cc LSx castings, Trick Flow's diverse product line runs the gamut.
With the competition more fierce now than ever, trying to maintain dominance in the cylinder head market is no easy feat. Al Noe of Trick Flow is well aware of what it takes, and we were happy to listen in as he explained what goes on behind the scenes when developing a new set of heads. As we learned, flowbench numbers aren't everything. Manufacturing a powerful as-cast port is tricky. Furthermore, modern advances in cylinder heads mean that small-displacement combos can now make some serious torque, and hardware once considered exotic like 18-degree top-end kits is more affordable than ever. Tune into the next few pages, because the guy in the other lane could be listening in.
Although Trick Flow heads have helped countless Camaros and Novas stomp Blue Ovals on a regular basis, the company entered the musclecar market in 1983 with its now-legendary A460 Ford heads. At a time when big-block Chevys and Chryslers dominated race tracks, the A460 cylinder heads gave big-block Ford enthusiasts the edge they needed to compete and win. Their success opened the floodgates to over 25 years of Trick Flow's trademark performance and innovation. The company soon discovered the need for affordable, high-quality cylinder heads for small-block Chevys, and developed a set of 195cc casting with Kenny Duttweiler's help. Capable of supporting 500 hp right out of the box, they gave the company instant credibility in the Chevy camp.
"Since that time, based on our customers' input, we have developed many variations of cylinder heads ranging from 18-degree small-block castings to oval- and rectangle-port big-block Chevy offerings. We've also gotten heavily involved with the GM LS engine platform, and our 13.5-degree heads can be had fully CNC-ported with 205-, 215-, 225-, 235-, or 245cc intake runners," Noe explains. "Trick Flow's goal is to make high-performance cylinder heads for everything from a hydraulic flat-tappet, pump-gas 283 to a blown 7-second monster big-block like the one in Denny Terzichs '67 Camaro that won Hot Rod Drag Week in 2007. We will continually innovate, test, and improve our products to make sure they are the best available."
All Trick Flow products are 100 percent cast and machined in the USA. We feel this is important for a number of reasons. When we specify T6 heat-treated A356 virgin aluminum, our casting suppliers will supply test bars, which we can physically and chemically test to ensure that their quality meets our specifications. Overseas suppliers will not provide material certifications with their castings. In some cases they may have fewer alloys to choose from and do not have any group such as the ASTM (American Society for Testing Materials) to regulate exactly what they use.
Another disadvantage with offshore sourcing is the long lead times. That means making changes to ports and chambers can't be done quickly. This isn't as big of a problem with CNC heads if the port work is done in the U.S., but it can really compromise the quality of as-cast cylinder heads. Having our castings done in America may cost a little more money, but we know exactly what we are getting and can ensure that our customers receive an excellent product. Since we use only top-quality components, we can back our product with a great warranty program. Plus, we can help keep jobs here in the U.S.-Al Noe
Trick Flow heads have earned a reputation for delivering outstanding performance right out of the box, and that didn't happen simply by chance. Using a proprietary process called Fast As Cast, Trick Flow is able to produce as-cast cylinder heads that offer performance very close to CNC-ported heads for a lot less money. "We start with one of our CNC-ported cylinder heads, then make intake and exhaust port tooling based off of the port shapes. Casting technology and our method of locating the intake and exhaust cores allow us to tightly control the tolerances, so the port shapes are much more exact than we could have achieved five to ten years ago," says Noe.
Trick Flow also offers fully CNC'd version of several of its cylinder heads, which deliver the ultimate in power but at a slightly greater cost. "To assist in the R&D process, we utilize two in-house Superflow 901 engine dynos that allow us to evaluate several port or chamber designs before putting a head into production. We benchmark virtually every cylinder head on the market to honestly evaluate how good our products are in relation to our competition, and to see what we can do to make better products. Competition in our industry is definitely a good thing for the performance enthusiast, as it compels us to constantly improve our products and keep them affordable."
Flowbench vs. Dyno
A flowbench is a great tool, just like the CFD (Computational Fluid Dynamics) software that we use. In addition to measuring airflow, some flowbenches can even measure air swirl and tumble. But what do the numbers really mean? For example, a head that flows great peak numbers but performs poorly at low and mid lift will often run like a dog on the dyno. A head with lower peak numbers but excellent low and mid lift will destroy the lazier head on the dyno. The flowbench and CFD software are good places to start, but we must use the dynos to verify their findings. Consequently, the dyno allows us to look at combinations objectively.
Believe me, our dyno guys do a great job of giving us a much needed reality check from time to time. Ultimately, this allows the customer to know exactly what they're getting before they invest in our products. For instance, we sell bundled top-end kits for first-gen small-block Chevys and LS engines, which include matched camshafts, rocker arms, and gaskets. When a customer buys our 515hp LS1 kit or our 550hp LS2 kit, we know for sure that it will make the power we say it will, and we have the numbers to back up our claims.-Al Noe
Serious Gen I Power
The increasing affordability of the LSx platform has many traditionalists jumping ship, but thanks to products like Trick Flow's 18-degree heads, the old-school Mouse has plenty of fight left in it. On the company's 406 small-block with 12:1 compression, a 266/270-at-0.050 solid lifter cam and an Edelbrock Victor intake, Trick Flow's Ultra 18 race castings belted out a staggering 731 hp and 543 lb-ft. Those impressive numbers resoundingly back up the company's published flow numbers of 334 cfm at just 0.600-inch lift.
Although converting to an 18-degree top end requires some specialized valvetrain components, it's not as exotic as some people think. "For a max-effort small-block, the 18-degree heads really are hard to beat," says Noe. "Even though a lot of unique parts are required, if the engine is planned and built specifically for 18-degree heads, the cost is not unreasonable. Compared to a conventional 23-degree motor, all you need to complete the swap are 18-degree-specific pistons, intake manifold, headers, offset lifters, and shaft-mount rockers. Since those are parts you'd probably buy when building any all-out small-block, the cost difference between a max-effort 23-degree motor and an 18-degree motor isn't as much as it may initially seem."
Researching and developing a cylinder head is an exhaustive process. Trick Flow starts with a list of objectives it wants to accomplish in terms of performance, price, and parts compatibility. Sometimes a benchmark is established based on a competitor's head, and the goal is to improve upon its performance. "The actual design process starts when we develop a flowbench model and test several ports and chamber designs. Once we have a starting point, we then make foundry tooling to cast the heads, machine them, and then implement the first port and chamber design," Noe explains.
With a working model now in hand, the head is flowed and dyno-tested, and then after several revisions the final port and chamber design is determined. This final design is dyno-tested for both power and durability. "After 40 straight hours on the dyno in which the loads and rpm are continuously cycled, we then disassemble the heads and check all the clearances and measurements to make sure they are within acceptable limits. We also check all the wall thicknesses of the castings to ensure that we have adequate wall material everywhere. It's not until we are satisfied with the power and durability that we put the head into production."
23- Vs. 18-Degree Heads
Granted, high-end 18-degree heads have become much more affordable in recent years, but many people still prefer the simplicity of a more conventional top-end package. "Typically these enthusiasts already have 355- or 383ci engines and want to step up to a 406 or 427, but want to retain their 23-degree-style rocker arms, intake manifolds, and headers," says Noe. To suit these applications, Trick Flow developed its Super 23 Race CNC 230 head. According to Noe, it is ideal for large-cubic-inch engines, retains the stock port location, and will come darn close to making the power of an engine equipped with 18-degree heads. "Right out of the box, these castings made 640 hp on our 11.5:1-compression 406 dyno mule with a 260/270-at-0.050 solid-roller cam. In our opinion, for an application that needs a large port and large runner with a projected output between 500 and 700 hp naturally aspirated, the Super 23 CNC head is the best bang-for-the-buck product, hands down. It's probably as close to an as-cast, 18-degree head as you can get in a standard 23-degree configuration."
New LT1 Heads
Although aftermarket parts development for the Gen II small-block has somewhat stalled in recent years, Trick Flow hasn't forgotten about the LT1 crowd. The company introduced its first LT1 castings in 2004, but has recently revised the design based largely on customer input. "Making a small-chamber LT1 head flow well was a challenge, and with the standard 23-degree valve angle, we were not able to meet our performance objectives. As a result, we rolled the valve angle 2 degrees, which allowed us to run a stock-sized chamber without cutting into the valve seat when decking the head," Noe explains. "Rolling the valve angle also helped us achieve our airflow and power targets. Additionally, we port-matched the intake entry so it precisely lines up with the doweled location of the LT1 intake gasket. Overall, it is an excellent design that will easily make in excess of 500 hp with a mild hydraulic cam."
"Our GenX Street 205 is a small-runner head that works incredibly well on small-bore 4.8L or 5.3L engines," Noe explains. They feature 58cc chambers and 2.00-inch intake valves that work well with the small 205cc runner size and clear the factory bore. Of course, they can also be used on 3.900-inch stock-bore LS1s.
"We tested a set of CNC-ported Street 205s on a 10.28:1-compression 5.3L engine with one of our 216/220-at-0.050 cams, the factory truck manifold, and a 78mm throttle-body. The combination made 456 hp, but what was even more impressive was the torque curve. The engine peaks at 425 lb-ft, but makes over 400 lb-ft from 4,000 to 6,000 rpm. That's pretty decent for a 325ci motor with a near-stock idle!"
Despite Trick Flow's vast selection of small-block cylinder heads, the company cut its teeth on big-blocks. It offers several sets of potent Rat motor castings to keep the mice at bay. Trick Flow's 280cc PowerOval heads are designed for engines up to 468 ci and feature 2.19/1.88-inch valves and 113cc combustion chambers. "These heads flow 347 cfm and make tons of torque. On our 460ci test motor with a 248/254-at-0.050 solid-roller cam and 10.25:1 compression, they made 605 hp and 556 lb-ft of torque," Noe says.
For more serious combinations, Trick Flow offers rectangle-port castings in both 320- and 360cc configurations with 122cc combustion chambers. "Our PowerPort heads move enough air to support up to 600 ci. On our 490ci test motor, the 320cc castings made 730 hp and 596 lb-ft with a 280/288-at-0.050 solid-roller cam."
GM's LS engine platform is really starting to catch on in the hot rod market. Our CNC'd GenX 215cc head features 64cc chambers and 2.040-inch intake valves. Our CNC'd GenX 225cc head has a slightly larger 65cc chamber and a larger 2.055-inch intake valve for 4.000-inch-bore applications. Our CNC'd GenX 235cc head has 70cc chambers and 2.080-inch intake valves for very big-bore application, and it flows 340 cfm right out of the box. We have a customer who has used this head in a late-model F-body drag car, and with a hydraulic roller cam and single turbo, the car has gone 8.0s! Lastly, our CNC'd GenX 245cc head is for motors displacing upwards of 440 ci, or applications intended for heavy power-adder usage. We also just released an LSX-R "porters" casting, which can support up to a 265cc intake runner.
In addition to our CNC-ported heads, Trick Flow also offers LSx heads utilizing our Fast As Cast intake and exhaust runners that incorporate CNC'd chambers and bowls. For about the same money as a set of ported factory heads, you get new castings with thicker decks, premium valve springs, stainless valves, and our 13.5-degree valve angle. They're a great value for the budget-minded enthusiast.-Al Noe
Not Just Heads
Trick Flow also manufactures a dizzying array of complementary engine hardware, which include rocker arms, pushrods, timing sets, fuel injectors, throttle-bodies, pulleys, camshafts, cold-air kits, valvesprings, valve covers, fuel pumps, gasket sets, and lifters. Likewise, Trick Flow has recently teamed up with Magnuson to offer complete Roots-style supercharger kits for EFI and carbureted motors. "They boost power output by 100-150hp, and drive like stock until you hammer the throttle," says Noe. "Our EFI lineup includes kits for 4.8L, 5.3L, and 6.0L LS-style engines. One of the most exciting developments at our shop is that we've recently started developing a blower kit for the '10 Camaro. Obviously, all these blower systems can benefit greatly when matched with a set of our heads."
Inside The Shop
The most important asset at Trick Flow is our staff. Our employees typically have over 10 years with the company, and they do an excellent job of treating the facility and the equipment like it is their home. They're passionate enthusiasts who race what they sell. When a company is made up of people who love what they do, it makes a huge difference in how we approach our duties on a daily basis. That said, the equipment our employees operate is impressive in its own right. We have solid modeling software for parts design, CFD (Computational Fluid Dynamics) and FEA (Finite Element Analysis) software for analysis, three flowbenches, two engine dynos, and a bunch of three-, four-, and five-axis CNC equipment, which can make anything we need. Furthermore, we make all our tooling at our in-house pattern shop whose staff has over 100 years of combined experience. Not many people can say that.-Al Noe
Part of the fun of a heads-and-cam swap is gathering individual components piece by piece, but it often leads to mismatched components and long downtime. To help simplify the process and save customers a few bucks along the way, Trick Flow offers bundled top-end kits for small-block Chevys and LS-series motors. The kits include a set of cylinder heads, a matched camshaft, roller rocker arms, pushrods, head and exhaust gaskets, head bolts, and a balancer bolt, all under one part number. "The main advantage of buying one of our top-end kits is that all the parts are matched and dyno-proven. If you use the same short-block as we tested our parts on, your engine will make at least as much-and in most cases more-power than what we claim," says Noe. "Our GenX 515 top-end kit for LS1s includes a set of 215cc heads and a 228/230-at-0.050 cam. On our stock GM 5.7L LS1 short-block with an LS6 intake manifold, this combo made 515 hp and 460 lb-ft of torque. With a little more compression, this combo can certainly add to that tally. At the end of the day, dyno-proven power, less headache chasing parts, and saving money are the major benefits of our top-end kits."
Valve Angles & Raised Ports
Today's hot rodders are better educated than ever and are very much privy to the benefits of flat valve angles and raised ports. That said, a flatter valve angle doesn't necessarily equate to superior airflow, and is very much interrelated to intake port location. "Factory LS-style heads have 15-degree valve angles, and that was no accident on the part of GM engineers. Although tipping the angle does indeed position the valves closer to the center of the bore and away from the cylinder walls, perhaps the biggest benefit is that it straightens out the port," Noe explains. "This means the intake port is raised, which yields a more gradual turn at the short-side radius and a straighter shot into the chamber for improved airflow. So while it's true that a flatter valve angle improves airflow, it's only one factor in the overall port design. In the case of 18-degree heads, the use of offset lifters and rockers allows the port to be made wider and taller to further improve line of sight to the intake valve."