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Oldsmobile 468CI - 500hp Engine Combos

Anyone Can Build

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500hp engine combos

This 461ci Olds sits between the wheelwells of Tim Meirick's '70 442 running a slightly different combination of Edelbrock heads, 240/246 0.541/0.544-lift cam, and an Offenhauser Port-O-Sonic intake with an Edelbrock 750 carburetor. It runs 12.50s at 109.

You asked for it. Our reader surveys say you want 500hp engine combos, and while there are several ways to get to that number, the majority of you want to see it without nitrous or a blower. It's seems that 500 hp is the new the 400 hp because everybody claims to have it and it seems easy to get. But is it? What has changed in the last 10 years that allowed an easy 500 to happen? The answer lies in huge jumps in cylinder-head design, low-dollar stroker cranks from overseas, and roller-cam technology that gives you lift and duration without the overlap and valvetrain wear. In this story, we've assembled eight engine combos that are easy to build with available parts, run on pump gas, and are the most economical use of factory blocks we could find. Drop one into your musclecar and feel what 500 hp is all about.

Oldsmobile 468ci

Making 500 hp with a big-cubic-inch engine is relatively easy because of the engine's size. In terms of power, this isn't even 1.1 hp per cubic inch. There is really only one limitation to cranking this much power from a big-block Olds: cylinder-head flow. According to Olds guru Dick Miller of Dick Miller Racing (DMR), it's possible to make five big ones with stock iron heads--he prefers the early A, B, or C casting heads, but ultimately it will cost more to have DMR port your iron heads than to just buy a set of Edelbrock Olds Performer RPM aluminum castings that are ready to bolt on. Keep in mind that these heads require roller rockers that also add up on the bottom line.

As for a camshaft, Miller recommends a DMR-spec flat-tappet hydraulic with 244/246 degrees of duration at 0.050-inch tappet lift with 0.534/0.544-inch valve lift at a 1.6:1 rocker ratio with a lobe separation angle of 113 degrees installed with the intake centerline at 110 degrees ATDC. The earlier 455 engines enjoyed a stock 10.25:1 compression, while later engines dropped to roughly 8.5:1. More compression for the later engines can be gained with Speed-Pro forged pistons that will also add durability.

Miller suggests the Edelbrock Torker as the intake of choice, since it's worth a solid 20 hp over the dual-plane Performer. A 1-inch spacer will add another 10 hp, but unless you've got a cowl hood, the taller combination won't fit. A typical Holley or Speed Demon 750-cfm carburetor will offer excellent power and road manners, and 36 degrees of timing from a reliable distributor will make the most power. Miller also likes the Kooks 134-inch long-tube headers, but they cost more than the Hookers. The bare minimum exhaust is a mandrel-bent 212-inch system. While a 3-inch will probably make the best peak power, it will also be heavier and louder than the smaller pipes. Power should be right at 500 hp at around 5,400 rpm with peak torque of around 570 to 580 lb-ft at 4,000 rpm. This is not a high-winding package, which means shifting a big Olds at 5,700 to 5,800 rpm will deliver excellent results of high 11s at 115 mph in a 3,800-pound Cutlass with a gear ratio taller than 3.73. With gobs o' torque, you don't need much gear.

Parts List
DESCRIPTION PN SOURCE PRICESpeed-Pro forged pistons, 10.25:1 L2323F-30 Summit Racing $319.60Edelbrock RPM 455 heads 60519 Summit Racing 1,579.00Edelbrock head-bolt kit 8558 Summit Racing 95.88Edelbrock Torker 455 2730 Summit Racing 267.88Fel-Pro head gasket 1155 Summit Racing 63.95Harland Sharp 1.6 rockers S5011 DMR 299.00Hardened 38" pushrods 5678-GP DMR 179.00SCE intake gasket 179102 DMR 12.77Hyd flat-tappet camshaft custom DMR Call

Dick Miller Racing; Hernando, MS; 662/233-2301;

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