 This computer-generated cross...  This computer-generated cross section of the ports (blue intake, red exhaust) shows the generous short-side turn radii used. |
 UNC Charlotte Motorsports...  UNC Charlotte Motorsports student Nathan Bornitz runs the numbers on a computer-controlled Saenz (www.saenzdynos.com.ar) flow bench. The long-term averaging capability of this bench is an asset to accuracy. |
 The port forms around the...  The port forms around the guide bosses are critical to flow. In the case of the intake (green), the guide boss also is used to influence swirl in a positive manner. |
 The smaller-than-usual intake...  The smaller-than-usual intake port proved highly active over its entire area. This gives the column of air in the intake port/runner greater ramming capability from the momentum involved. |
Although CFD could do much to show pictorially where and how air was traveling through the cylinder head, Losito still chose to validate any such information by thoroughly velocity-probing all the areas of concern on the flow bench.
OK, so much for wandering off into the land of high-tech computational flow testing. Getting back to terra firma and moving on from valve angles, Losito addressed the intake port positions at the intake flange face. Using what has been developed for Cup car racing as a starting point, the port shape and position were reevaluated. Since this head was not constrained by NASCAR rules, Losito had greater freedom to be more innovative with the intake port. What he found was needed could not be had from the SC1 casting. On top of that, the relocation of the valves also meant the rocker locations had to be revised. That in itself was cause for some serious casting changes to become necessary.
At this stage, a pair of dyno-proven prototype heads were carrying an indecent amount of weld, so the next problem to address was to get a new, redesigned casting into production. Here, Losito worked closely with Ford engineers. Externally, the most obvious change, if you were to check with a caliper, was the extra 200 thousandths on the intake manifold face and the modified rocker pads.
What cannot be readily seen, however, were the changes made in the water jacket-among these changes were some to make the castings more porter friendly. The principal ones here were the thickening up of the material under the short side turn of both the intake and exhaust. Another such move was increasing the thickness around the intake bowl. Once the new castings were done, it would seem that Losito had a winner on his hands. Not quite. He is as fussy over his projects as a mother hen over her chicks. With a new head casting to work with, a substantial number of refinements were made and tested. None of these were of major significance in themselves, but when the sum total was considered, it all added up to something worthwhile.
On the dyno, the heads produced satisfying numbers, even for the most power-hungry racers. In fact, Losito selected some of these racers to do the field testing. These included multiple Dirt Late Model champ Scott Bloomquist and ARCA champ Frank Kimmel. As for drag racing, this was considered to be of prime importance as it was a venue to test the valvetrain to some stratospheric rpm in the 10,000-plus region. Though it might seem somewhat removed, the drag contingency was actually testing in order to quell the reliability fears that NASCAR Ford teams historically had with previous heads and valvetrains.
In 2001, Ultra Pro Machining canted valve heads went to Penske, Yates, and Roush, but the then-current race pressures and politics (just keeping up with the busy race schedule was more than enough to deal with) precluded any serious testing. This, in part, was because NASCAR was comfortable with the balance of power between the various brands of cars, and was reluctant to approve the new headIn 2003, both Chevy and Dodge made some serious improvements in output, thus upsetting the competitive balance between the three manufacturers competing. This caused a reevaluation of the situation that led to Ford ordering UPM's then-latest version of the Ford SC1 canted valve heads. Working closely with Roush, a test engine was built and dyno tested. Just about everyone present was impressed with the results. Ford then submitted the head design to NASCAR, and in the fall of 2003 gave the head design approval.
At this, UPM had to consolidate the head design to be sure it met all of NASCAR's template requirements for port centerlines and heights. From all this emerged the casting and port/ chamber configurations that helped Kurt Busch win his first Nextel cup championship in 2004. It also was instrumental in placing five Ford-powered cars into the chase, with 2005 seeing five more Fords added.
Since its introduction, the D3 casting-based UPM canted valve heads have won literally hundreds of races in the top and most competitive classes in the country as well as an enviable number of championships. These classes include drag racing, Dirt Late Model, ARCA, Nextel Cup, Busch GN, Craftsman Truck, Silver Crown, Sprint cars, Midget, and Off-Road. Depending on the application, there are a number of port configurations that UPM can supply. It can be very flexible in this area because it starts with a raw casting. If you want to talk versatility and big power, try 2,400 hp from a turbo motor.
Our Evaluation
So much for the UPM canted valve heads pedigree and success to date. Now it's time to take out our magnifying glass to see what makes this head such a powerhouse. Dyno testing on anything less than an all-out spec engine won't prove much, and we can't afford to build one just to show you such results. But we do know that a good Nextel Cup engine (remember, that's a flat-tappet deal) makes over 840 hp with these heads. What we can show you are the results of our flow testing on UNC Charlottes flow bench. Since big and possible controversial numbers were expected, the bench had its calibration checked immediately prior and subsequent to our tests. As a result, the confidence level of these numbers is to about the 1 percent accuracy mark.
Let's start by perusing the flow numbers in the flow chart. On the intake side, the number that most of you are going to be impressed with is the 434 cfm of peak flow. There are a lot of performance big-block heads out there with intake valves bigger than the 2.180 inch ones this head is equipped with that don't match that number.
As good as this may be, the number that really impressed us was the flow at 0.250 lift. The best head we have done with that size valve flowed 186 cfm at 0.250. On our list of all-time bests, that ranks in third place. Second was a GM head, which as it happens was a UPM head that flowed 188 cfm. At this stage of the game, a couple of cfm improvement represents a hard-fought deal.