Rocket Man

The end may have come for General Motor's Oldsmobile division in 2004, but faithful fans of the brand are relentless in their quest to improve the breed. And while Oldsmobile, as a make of car, may have lost its high-performance roots on the journey toward its final years, the history of Olds performance is enough to make any fan proud. Notably, Oldsmobile (concurrently with Cadillac) launched the modern era of the high-performance V-8 with the introduction of the "Rocket 88" overhead-valve V-8 in 1949. The original Olds V-8 began as a 303-cube powerplant, and the same architecture carried on to 1964, in displacements up to 394 ci. The early Olds gained quite an enviable reputation in the dawning days of hot-rodding, but in keeping with advancements of the time, an all-new engine design debuted in 1964, to carry Olds through the musclecar era and beyond.

The "modern" Olds V-8 was introduced as a 9.33-inch, short-deck, small-block, 330-inch engine in 1964. That same basic design was carried over in a 10.625-inch tall-deck version to create the long-stroke big-block Olds 400 and 425 the following year. Deck height is the major distinguishing characteristic between the small- and big-block Olds brothers, as they shared the essential architecture. From its original displacement, the Olds small-block went on to be produced in 260-, 307-, 350-, and 403-inch versions, while the original tall-deck Olds big-block line was augmented with the introduction of the 455 in 1968 (see sidebar, pg. 87). This new engine design was adopted for Oldsmobile's muscular, 442 mid-sized performance car, with the 400 engine's availability in 1965.

And the legend only grew through the '60s. First was the offering of the significant W-30 performance package on the 442. Next came the 455-powered Hurst cars, beginning with the redesigned Cutlass in 1968, and then the hot small-block W-31 350s were offered in 1969 and 1970. The year 1970 was particularly important for Oldsmobile enthusiasts, as the 455-cube monster was finally available in the mid-sized Cutlass 442. Further fueling interest and excitement was the unique Dr. Oldsmobile advertising campaign, as well as numerous contemporary magazine stories elaborating the details of Olds performance-stories which didn't go unnoticed by a young Dick Miller.

Dick Miller - Rocket Man

Miller needs no introduction to those familiar with Oldsmobile performance, having built a reputation on some of the stoutest examples of Rocket power anywhere. Just what sparked his long association with Olds? As Miller tells it: "I saw a magazine article on a 1970 W-31. James Garner had one, and the article sort of read that you could buy one of these off the showroom floor, take them racing, and away you go. [PHR, Mar. '70-ed.] Well, being naive and as young as I was at the time, I bought one and found out that was just the beginning." Miller continues, "In 1969, I bought a brand-new 1970 Olds Cutlass-and I still have it. I just started drag racing, and by the mid '70s I was running NHRA Stock Eliminator. Later I got into brackets, and I built a few engines over this period. In the early '90s, I built a '91 Cutlass tube-chassis car, and was running NHRA Super Comp and Super Gas with that. I got involved as an Oldsmobile parts distributor then. In 1994, I started my own business, Dick Miller Racing [DMR], doing what I am doing now: racing, selling parts, and building engines."

432-Inch Powerhouse

The engine featured here was built by Miller to compete in the 2006 Jeg's Engine Masters Challenge, an annual engine building competition sponsored by Popular Hot Rodding. He has been a regular competitor at the event, always one to showcase the Olds' potential. As Miller relates, "It's a great chance for me to get out there and have people see what I am doing. Last year's 434ci limit worked out well. Since a .030-inch overbore 425 comes out to 432, I was able to run a stock stroke and stock bore with a .030 overbore, and I was there." In fact, Miller's engine is based on a production Olds 455 passenger car block, with a factory forged 425 crankshaft. He explains his objectives this way: "I'm not necessarily in the contest to win outright, but more to develop new products, show people what's available, and what can be done. Like the 403 engine we brought last year: most people don't think the 403s are worth anything, but we made 600 hp, and got it to live and stay together, even with that windowed main web people are afraid of."

Commenting on the blocks, Miller reveals to PHR: "At 500 to 550 hp, they are great. We have a few options in girdles: a halo girdle that connects the first four mains, a halo girdle that attaches all five mains, and then I have what I call a pan rail girdle, which attaches like the halo girdle, but also attaches to the pan rail." He informed us that the older blocks are said to have a higher nickel content, and are considered stronger from a metallurgical standpoint; but in his experience, they all hold up quite well, especially with a girdle installed. In fact, Miller said he has never experienced a block-related failure in all these years of building and racing Oldsmobiles. As extra insurance, this engine was built with premium ARP fasteners at all critical points.

For the power output anticipated in this build, the basic production components were righteously fortified, using a DMR girdle system and Miller's beefy billet main caps. Although the crankshaft was plucked from a factory engine core, Miller had Crankshaft Specialists rework the 'shaft with a custom knife-edging and lightening job, as well as hard-chroming the journals. A DMR windage tray provides further oil control and windage reduction. The stock 455 3.000 journals were retained on the mains, while the rod journals were ground to 2.200 inch, to accept the Oliver 7.000-inch big-block Chevy connecting rods. To achieve the 10.5:1 compression mandated by the rules of the Engine Masters competition, Miller had CP Pistons deliver a set of custom forged pistons in a dished configuration. Aiding in overall power production was a low-friction ring set from Total Seal, with narrow .043 compression rings used in conjunction with 3mm oil rings.

Coatings For Power

The engine made use of quite an extensive array of coatings from Polymer Dynamics. The outsides of the intake manifold and cylinder heads were coated (primarily for cosmetics, according to Miller); however, it didn't stop there, as nearly everything inside was coated, too, including the crank and rods, for oil shedding. A dry film lubricant was used on the oil pump gears, and the piston skirts received a similar treatment. The tops of the pistons were thermal-coated, as were the intake and exhaust runners, the valves, the combustion chambers, and the bottom of the intake.

Miller explains that the Olds engines build a lot of torque, but admits that the oiling systems need some work (though he has developed techniques to correct these shortcomings). Overall, he considers the Olds a straightforward engine to build. Oldsmobile uses a shallow stock valve angle (at 6 degrees), and he says: "For the cfm that an Oldsmobile head flows, they'll make more power per cubic inch than most of the other heads out there." Until recently, there weren't many choices in aftermarket heads, but now options are opening up. Miller tells us that the Edelbrock heads are similar in design to the original cast iron heads, limiting the all-out potential. For this engine, he went with the Bulldog heads, which he finds to have greater power potential. He used the offset pushrod version of the Bulldog head, which moves the intake pushrod clear of the intake runner, to offer room for larger ports, and ultimately more flow. Flow peaked at 385 cfm in fully ported form, as reported by Miller.

Deep Breathing Induction

A carefully crafted induction system plays a major role in a successful engine build, and here Miller began with an Edelbrock Victor intake manifold with a 4500 Dominator base. As with the cylinder heads, the intake manifold was subject to development work and porting to maximize airflow and distribution-both major factors in the engine's overall flow system. Though the manifold carried a 4500 base, he settled on a 4150 carb to provide the mix. Rather than run an adapter or spacer to mate the carb with the manifold's bolt pattern, the carb was fitted with a special 4150 adapter base, which carries the 4500 bolt pattern for a bolt-on installation to the manifold. The Holley experts at the Carb Shop handled the requirements for the specialized "tuner" carb.

Another key area for power enhancement on this production-based engine is in the camshaft. Miller favors the use of COMP Cams' profiles, and here he chose a solid roller with a moderate duration in the mid 240-degree-at-.050 range, in an attempt to make power over the range from 2,500 to 6,500 rpm. Despite this relatively conservative duration specification, the fast-acting lobes of the custom camshaft deliver a stout level of valve lift (at .775/.730 inch with 1.6:1 ratio rockers). The high lift helps tap into the excellent high-lift flow of the modified cylinder head castings, and Miller worked in conjunction with COMP to develop the camshaft just for this engine combination. The camshaft works in a team with COMP roller lifters, springs, titanium retainers, and 10-degree SuperLocks. Harland Sharp roller rockers communicate the cam's motion to the valves.

Miller was poised to put on a good showing for Oldsmobile power in the 2006 Engine Masters Challenge; however, a fluke problem with the valvetrain eliminated the engine before it had a chance to really show its stuff. Even so, preliminary numbers in competition showed over 600 hp. Certainly, he would have liked to see the engine complete the competition, but ultimately it wasn't built specifically as a bullet for that event. As he tells PHR: "I built this engine to work in a real-world performance application, something that one of my customers could use." We say with that kind of power and torque on hand, this Oldsmobile really earns its "Rocket" moniker.

Oldsmobile Lifter Bank Angles

While most engine families carried the same lifter arrangement throughout the series' production run, Olds engines were produced with some unusual variations in lifter bank angle, and even variations in the lifter size itself. Blocks were cast with two distinct lifter bank angles: 45-degree and 39-degree. This is important to note, since a camshaft must be ground specifically for the geometry of the block's lifter bank angle, meaning camshafts cannot be swapped from one type of block to the other. Another quirk is that the blocks were manufactured with two different lifter diameters-some were machined for .842-inch lifters, while others were made to accept unusually large .927-inch lifters.

So which engines got which setup? Initially, the Olds engine began with the 45-degree bank angle and .842-inch lifters found on the first year's production 330-cid engine in 1964-a setup retained in the 330 through 1967. The 400 began in 1965 with the same 45-degree/.842 combination, but changed to the 39-degree angle and .927-inch lifters for 1966 to 1967. Likewise, the 425 began in 1965 with the 45-degree/.842 combination, but for 1966 to 1967 it was produced with either the 45-degree/.842-inch or the 39-degree/.927-inch arrangement. The latter is said to have been used primarily on the 425 engine in the premium Toronado model. For 1968, the 39-degree lifter bank angle was standardized across the board in all Olds engines. Where the 39-degree lifter bank angle had previously been used only with the large lifters, the '68-and-later engines all used the 39-degree lifter bank angle with the smaller .842 lifters.

Sources

Dick Miller Racing

662-233-2301

www.dickmillerracing.com