At PHR's annual engine-building shootout, the AMSOIL Engine Masters Challenge, many of the competitors fall into one of two camps. There are the guys whose engine platform of choice is the one that they feel best stacks the edicts of the rulebook in their favor. Let's call them the pragmatists. Since making horsepower is all about optimizing airflow, it's not surprising that the engine platforms with the broadest selection of potent induction components are often the most popular. At the other end of the spectrum, there are guys who will build their favorite engine platform of choice no matter what, rules be damned. Let's call them the passionate loyalists. From Cammer Fords and Pontiacs, to AMCs and Buicks, thank goodness for the men who love these motors, because they're the ones who add a big wallop of intrigue and spice to the competition.
Big displacement is the big-block Ford’s specialty. Thanks to a commodious crankcase, a pr
Todd Miller of TM Enterprises is a Ford Boss 429 fanatic, and for him the choice was between building a Boss motor or building nothing. He loves the Boss platform so much that he personally developed an all-new hemi cylinder head casting that bolts up to any Ford 385-series big-block. We say personally because Miller's a foundry mold and pattern maker by trade, not an engine builder, and he painstakingly dedicated his free time to designing a set of brand-new cylinder heads for the Boss faithful. Not only does the AMSOIL Engine Masters Challenge provide a great excuse to show off his new Boss head, but the lessons learned from competition also serve as a great opportunity to further refine and develop the TME product line.
Seriously Big Boy
Among the 31 engines that competed in the 2012 AMSOIL Engine Masters Challenge, TME's Shotgun Ford was the largest at 545 ci. In fact, most of the top finishers in the Street Division fielded motors that measured 100-150ci smaller, which is no coincidence. While the EMC scoring system divides the horsepower and torque averages of an engine by its cubic inch total to neutralize the benefits of larger displacement, all Street Division engines must exhale through a pair of 3-inch Flowmaster mufflers. This presents a substantial handicap for larger engine combinations, but Miller didn't care. "A 545 is way too big of a motor for the small exhaust you have to run, but this short-block is basically a test mule for our parts development, which means it has to be representative of what one of our customers would build for a street car. A small-bore, long-stroke motor with half the intake port volume filled in would be a better setup to score a lot of points with, but this engine isn't a dyno queen or a ringer by any means," Miller explains. "Given the tremendous airflow capabilities of the Boss cylinder heads, in a street application there's no reason to bolt them to a small motor. These Boss motors love lots of cubic inches. Since it doesn't cost any more to build a bigger motor and you have the cylinder heads to feed it, you might as well put a long-arm crank in it and let it eat."
In addition to long cylinder sleeves, tall-deck blocks offer thick piston compression heig
A closer examination of the Ford 385-series big-block architecture reveals why Miller decided to defy convention and go big. Simply put, big-block Fords are easy to build big, but it's hard to make them small. With a 4.900-inch bore spacing and a 4.360-inch bore, a factory 460 Ford dwarfs the 4.840-inch bore spacing and 4.250-inch bore of a 454 Chevy. Furthermore, while the 4.390-inch bore dimensions Miller settled upon might seem somewhat large, Blue Oval boys routinely open them up to 4.440 inches and larger. When it comes to deck height, the 385-series block stands tall at 10.322 inches with a cam tunnel pushed way up high in the block. This allowed Miller to drop in a 4.500-inch Scat forged crankshaft without having to grind down the rods or crankcase for clearance. He matched them up with a set of Scat H-beam 6.800-inch steel rods and Diamond 10.5:1 pistons. In contrast, a 9.800-inch deck factory 454 Chevy block typically requires a fair amount of grinding with a 4.250-inch stroke. In other words, big-block Fords beg for big cubic inches, and it's no wonder that hot rodders often build them as large as 557 ci.
Practicality notwithstanding, the TME 545 more than held its own for a combination that wasn't optimized for the EMC competition, finishing 12th out of 20 entries in the Street Division. Much of that success is attributable to the combined brainpower of Miller and his partner in crime, Eric Simone of Shotgun Hemi Parts. Simone has done just about everything in a distinguished career that includes engine development work for Ford Racing, Roush-Fenway Racing's NASCAR program, IHRA Pro Stock, and NMRA Outlaw 10.5. Likewise, he has entered several of his own motors in past EMC competitions. In an effort to boost low and midrange torque, Miller and Simone spec'd out an under-square short-block that combines a 4.390-inch bore and a 4.500-inch stroke. Likewise, the COMP hydraulic roller cam provides .799-inch lift, but duration was limited to a conservative 248 degrees at .050. A tight 108-degree lobe separation angle shifts the power curve to the low and midrange as well. "The idea with the cam was to pick the valves up into the fat part of the lift curve where the heads move a lot of air, but then keep the duration relatively short to increase low and midrange output," Simone explains.