Rocco Acerrio of A.R.E. Performance & Machine of Simi Valley, California (www.areperforman
As we noted in the second stanza of this series ("Best of Both Worlds;" Jan, '10, p. 70), the term "racing" is somewhat global, with respect to the ways in which Mustangs are modified for and used in various types of motorsport competition. However, despite Mustangs' versatility-especially those equipped with the pushrod engines-drag racing is arguably recognized as the number one form of competition for daily driven and purpose-built Ponies.
Major differences are easily recognized when comparing hard-core racing cylinder heads to their streetborne siblings. Racing heads feature larger and more-elaborate, CNC-ported combustion chambers, and (exhaust) ports that are considerably raised to give air a smoother, straighter exit from the cylinder. They also feature thicker deck surfaces for flat and angle milling (to increase compression), and some have canted valves, which set them far apart from conventional heads.
While some of the street-and-track heads mentioned earlier can contribute to 1,000 rwhp, the big dogs that are included in this report all are capable of helping a Ford small-block engine produce power that is deep into the quadruple-digits with a power adder. Pricing for race-specific cylinder heads typically starts at $1,100 each-in some cases-for just the bare castings alone.
From a cost perspective, the heads being featured in this story are far beyond the needs and affordability of our core group of readers who own daily driven street 'Stangs. However, in the spirit of "equal time" for all of the categories of usage for which cylinder heads are made, we're closing out our series with the bad dudes that are detailed in the following photos and captions.
Air Flow Research
AFR's 225 cylinder heads (PN 1451; 58cc chamber and PN 1456; 72cc chamber; $2,019), are the next (and final) level in the company's small-block Ford head lineup. They share many traits of the 205s that the 350ci bullet in our '86 T-top coupe uses to generate 866 rear-wheel horses (stay tuned for an upcoming report on reaching that new power plateau). The larger heads are 100-percent CNC-ported and flow gobs (intake flow measures 324 cfm at 0.700-inch lift) of air across 2.08 (intake) and 1.600 (exhaust) valves. The 225s are recommended for 347-to-427 stroker engines that turn as much as 8,500 rpm. One important spec to note is that exhaust ports are seriously raised, to 0.375-inch taller than a factory head, which makes them as race-specific as it gets, in the grand scheme of things.
We bet almost everyone competing in the NMRA's Super Street Outlaw class already knows what Brodix Neal heads are. They're the canted-valve, raw-dog heads found on many Super Street Outlaw and Outlaw 10.5 engines. Yes, those castings make tremendous steam. However, Brodix also offers a little-known fully CNC-ported race castings for the classes that require conventional heads. While we couldn't confirm their NMRA legality, Brodix's Track 1 Fs (PN STS T1 F STD 214/214cc; 68cc chamber; 2.08-inch intake valve/PN STS T1 F STD 225/225cc; 68cc chamber; 2.10-inch intake valve; $2,744.38) appear to be suited for EFI Renegade-type engines. With intake flow of 334 cfm at 700-inch lift (for the 225s) and exhaust ports that are raised 0.500-inch from the factory big-cube, Windsor-based engines that spin to 8 grand are the type of engines that these Track 1s thrive on.
We used images of fully assembled Dart Pro-1 CNC cylinder heads and their bare castings (PN 13072143; 62cc chamber; 2.08-inch intake valve; with 1.550 [OD] double valvesprings, $2,910.70) to lead off our first two stories in this series, and they sit atop a complete Dart 347 long-block that we'll be telling you more about in a future issue. Pro-1 CNCs feature 225cc intake ports (2.150x1.300-inch) that flow 325 cfm at 0.700-inch lift, and equally as large, raised (0.135-inch) exhaust ports that flow 235 cfm.
Edelbrock's Glidden Victor II Pro-Port (PN 773169; $911/each; $2,225/each fully prepared by Kuntz and Company) cylinder heads are sold bare. They feature small ports and combustion chambers, and thick walls for heavy modification by professional engine builders and head porters. The castings are designed for racing classes that require in-line valve positioning (Victor IIs have an 11.25-degree valve angle) but allow port relocation. The big dogs of Outlaw 10.5 and Pro Street use hardware like this, as it truly is in the outer stratosphere for churning out solid power from a 9.2- or 9.5-deck, stroked, or 351W.
Glidden Victor SC-1 Pro-Ports (PN 770769; $1,025 each; $2,825 each, fully prepared by Kuntz and Company) are Edelbrock's top-of-the-line race castings. Like the Victor II Pro-Ports, these heads are served up in bare form only, leaving engine builders to the task of shaping, porting and designing a head that can flow as much as 440 cfm on the intake side. An 8-degree valve angle (SC-1 Pro-Ports feature a twisted-style combustion chamber for true, canted valves) are one of the keys to these heads contributing to the production of 2,000 horses (and then some) from big-cube, big-power-adder, small-block Ford engines.
Ford Racing Performance Parts
Ford Racing Performance Parts also brings a serious bare casting to the table for small-block Fords. FRPP's High-Port heads (PN M-6049-SC1; unfinished chamber [40cc-70cc]; 2.180-inch intake valve; $1,195 each) are canted-valve, raised-runner (0.400-inch over Yates C3 heads on the intake and exhaust sides) castings that also require extensive porting. With the right amount of time invested, the heads definitely can be formidable players on engines that power drag-, sprint-, and circle-track race cars.
Although Racing Head Service is better known for its Brand-X head castings, the company's Pro-Elite series for small-block Ford race engines should not be taken lightly. Pro Elites are RHS's biggest and baddest 20-degree cylinder heads for Blue Oval bullets; offered in 205cc and 221cc (intake-runner volume) configurations. Pro Elites (PN 35020/205cc; 62cc chamber; 2.05-inch intake valve; $1,846.32 and PN 35025/221cc; 62cc chamber; 2.08-inch intake valve; $1,846.32) are fully CNC ported and receive a multi-angle Serdi valve job prior to porting, which gains them as much as 5-percent more airflow. RHS recommends racers use the Pro Elite castings for 289-to-351W-powered drag and circle-track engines that get high in the revs.
Trick Flow's original High Port aluminum cylinder heads arguably are castings that helped kick off the high-performance, small-block Ford head revolution. And, as a testament to how good the OG heads really are, you can still find vintage High Port Street/'Strip heads on some of the fastest Fords around. Today's High Ports (PN TFS-51700001; 64cc chamber; 2.02-inch intake valve; $1,399.95/pair) still have the same patented valve spacing, interlocking ductile-iron valve seats, and thick decks as the originals, as well as excellent cooling characteristics. Most importantly, High Ports flow! Entry into each 192cc intake port has been reshaped to help seal the area along the port roof, and the 87cc exhaust ports are raised 0.750-inch over a stock head's port floor, to increased the exit flow of spent gasses (custom headers are required for High Ports).
CNC Race (also known as "R") cylinder heads (PN TFS-5240T005-C01; 65cc chamber; 2.08-inch intake valve; 225cc intake-runner volume; $2,949.95/pair) are the highest-flowing, bolt-on castings in Trick Flow's Twisted Wedge family. The ported, race-ready heads feature enormous (100cc volume) exhaust ports that are raised 0.500-inch from stock, and flow 341 cfm through the intake ports and 271 cfm out the exhaust ports at 0.700-inch of valve lift-in box-stock form. Other race-ready features include a 0.560-inch deck surface, spring pockets machined to accept 1.630-inch valvesprings for massive, solid-roller camshafts, bronze valve guides, tungsten alloy intake seats, and copper bronze exhaust seats. Trick Flow's R heads are solid out-of-the-box performers, but the castings can be purchased in bare form, too.