10 As you can see, the C&L manifold was designed to eliminate the factory charge motion c
"Aside from its aluminum construction, which is a substantially more durable material, it features an individual intake port flow capacity that is roughly 28 to 30 percent greater (on average) than the original intake," notes Bender. "This was accomplished by eliminating the 'crossover' runner design of the factory manifold. By keeping the port entry location for each respective bank of runners away from the other, we were able to maintain the same port shape throughout the entire runner. The stock 'crossover' manifold (due to front-to-rear port length and spacing) has to convert the runner from a round opening to the oblong shape of the factory port at the cylinder head. The runners are length-tuned to develop a horsepower peak that starts at around 5,000 rpm and extends to at least 7,000 rpm, and even higher if the engine is built to operate above that range.
"The total manifold volume has been increased by 1.1 liters, which gave us the best overall performance at all rpm points during testing. The factory charge motion control valve plates are completely eliminated ... and this saves the customer the trouble of having to purchase aftermarket delete plates. Every major characteristic of the manifold was adjusted and thoroughly tested in order to ensure we had the best possible configuration. This testing, along with that of third parties using various configurations, added substantial time to the finalization of the product, but it also ensured that we had done everything that we could to optimize the product.
11 C&L also opted to remove the center obstruction that the factory manifold incorporates
In noting the aluminum construction of the C&L intake manifold, we asked Bender why he opted for this material versus the factory plastic composite choice.
"Composite manifolds are ideal for OEM automotive manufacturers, as they offer a very low-cost product when you are creating very high volumes of manifolds. The up-front tooling costs are several times higher than what it costs to develop a mold for an aluminum product, but if the volume is there, the cost savings per unit can more than make up for it over time," says Bender. "Composite tooling is created from 3D CAD models in software; once the tooling has been cut, it may be necessary to completely re-do the tooling if you see the need to make a substantial revision or change to the product. This can become very costly, which is why most parts made in this manner are tested first as 'rapid prototypes' to evaluate and make adjustments until the product is right. Although these prototypes can be made rather quickly, they are quite expensive to create.
"We take a very hands-on approach to product design and development. Although 3D modeling is becoming more commonplace within our business, I still prefer to do most things by hand. In the performance aftermarket, the sales volume in most cases simply does not lend itself well to using composites for creating intake manifolds. The up-front tooling costs for aluminum castings may be less, but the time required to make revisions and adjustments is longer than with rapid prototyped parts."
For a suitable test subject, we turned to Hurricane Performance in Orange Park, Florida, which offered up its '05 Mustang GT shop vehicle. This Mustang is currently at the pinnacle of 4.6L, Three-Valve performance with its naturally aspirated 400-plus-rwhp status, and we thought the C&L intake manifold would give it a sizeable kick in the pants over the factory intake manifold. The Mustang features an Al Papitto-built (Boss 330 Racing) 302ci bullet based on a Ford Racing Performance Parts Boss 302 block. Kris Starnes ported and polished the stock heads, and a pair of Anderson Ford Motorsport prototype camshafts moves the air and fuel through the engine.
Installation of the C&L intake is fairly simple. The only real change between it and the stocker is the length of the bolts. Because C&L has eliminated the charge motion control valves from the intake tract, it uses slightly shorter bolts, which are provided. Total installation time was easily under an hour. Rather than offer a simple before and after test, we took the opportunity to run a few tests with different throttlebodies on both the stock and the C&L intake manifold. We were pretty pleased with the results on our naturally aspirated test subject, and we're eager to see what it will do on a supercharged or turbocharged application. MP
12 In case you're addicted to nitrous oxide, C&L incorporated these bosses so you can plu
13 Since the C&L intake does away with the factory CMCV plates, it requires a different l
14 Clearance between the bottom of the intake and the alternator case was too tight for o