Building A 721HP Buick Engine - Dream Up!

The history of Buick is filled with dreams, inspirations, and innovations. David Dunbar Buick built the first Buick automobile in 1901, and the next year created the first overhead valve engine for use in an automobile. Though David would leave his namesake company by 1906, the Buick Motor Company would live on to become the founding cornerstone of the General Motors empire. An impressive list of names worked for Buick at one time or another. Chief investor William Durant, Louis Chevrolet, Charles Nash, and Walter P. Chrysler were all key players for Buick. With forward thinking, the Buick brand often found itself on the cutting edge of technology. How was it, then, that the engines powering these cars were relegated to playing second fiddle in the muscle car world? That may be a question for the marketing historians. One thing is for sure though, engine builders like Mike Phillips of Automotive Machine and Performance are doing their best to ensure that the Buick powerplants don't play second fiddle to anyone.

Since opening his shop 22 years ago, Mike has always focused on performing quality machine work and pushing the horsepower envelope. About 12 years ago, he started to refine his focus, centering on the under served world of Buick high-performance engines. Several customers brought him engines with ideas that the Buicks had to be built a certain way, but Mike treated them like any other engine; finding inherent flaws and fixing them, maximizing the architecture of the design, and using his solid machining background to build reliable power. This formula helped him build one of the highest horsepower engines in the '08 Popular Hot Rodding Engine Masters Challenge.

To create his 464ci monster, Mike started with a factory 455 block and gave it the full Automotive Machine treatment. Buick V-8 blocks have always used a lightweight design, and though that makes for less expensive manufacturing, it does leave a little strength on the table. To beef it up, Mike used a main girdle from TA Performance. The girdle is a stout cast-iron piece that ties all of the main caps together, also attaching them to the oil pan bolt holes. When making north of 600 lb-ft of torque, this is a necessary step to ensure the life of the main bearings. Another piece to strengthen the block was a lifter-bore girdle. Similar to Pontiac and Olds engines, the lifter bores in a Buick V-8 just hang out in space, unsupported in the lifter valley. If a solid roller cam is used, the increased spring pressure and loading from the roller cam can break off the lifter bores from the block. The lifter bore girdle ties the bores together and prevents failures like that from ruining the day.

The oiling system is an area that Mike spent a good deal of time modifying. To begin with, he used an external -16 oil line from the pan to feed the pump. He explained that this alone solved a good portion of the oil flow problems. "There's a lot of harsh 90-degree turns in the block. There's four before you get to the gears, and there's three once it leaves the gears. And just like a fuel system on a car, you wouldn't dare put a 90-degree fitting on a fuel system. That's basically how the block is designed." He used a pump called a "scavenger" that bolts in place of the factory block-mounted pump, but really works as an external pump with external feed and pressure lines. "Everything up through our street stuff that we do, we don't put this scavenger on, but we radius all those 90-degree turns in the block." Often, the oil holes in the main bearings don't line up with the holes in the block, so some minor grinding on the block and opening up of the holes in the bearings is the solution. These modifications allow the Royal Purple synthetic to maintain 55 psi of hot oil pressure with just a standard volume oil pump. Mike says: "that's the life of the whole motor--just working on the oil system." Since the factory oiling system feeds the lifters first and then the mains, all of these modifications ironically presented the problem of having too much oil fed to the top end. Mike has tried a few different approaches to restrict the oil to the top end, including small orifice lifters and custom pushrods with a restricted orifice. Ever the thinking man, he found that he was able to modify stock-type pushrods with some silver solder and a small drill bit to get the restriction he wanted. With that bit of technology under his belt, he was able to use standard Comp Cams lifters and save the expense of custom lifters or pushrods.

The block supports, and the oil system modifications made the engine strong enough and reliable enough that he was able to use a stock cast-iron 455 crank to handle to the 720-plus horses. With a 3.25-inch main journal, there is more than enough material to handle the stresses. The stock rods had to go though, in favor of a set of Eagle H-beams. Known for their strength, they would have no problem holding the JE pistons in place. Mike stuck with a tried-and-true set of Speed Pro piston rings to seal up the combustion process. Speed Pro was also the supplier for the engine bearings. As for clearances, Mike says: "I do it just like I do a Chevrolet. Just like anybody would tell you 0.003 inch is the best cooling on a bearing, and 0.002 inch is best for load. So with the mains as big as they are on that, we try to have 0.0025-plus, and I don't mind going over 0.003 inch. On the rods, I try to stay right on 0.0025 inch."