Best Selling Engine Combos From Top Engine Builders - Proven V-8 Power Trends

A short-deck 582ci Rat motor... 

   

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A short-deck 582ci Rat motor can be easily passed off as a 496 or even a 454 if you're adept at subterfuge. It's the ultimate sleeper Rat. But you won't be able to use the Shafiroff valve covers. They're a dead giveaway.

Big-Block Chevrolet 582 CI
Talking with the crew at Shafiroff Race Engines, we learned that the most popular standard-deck-height Bow Tie rodent is the 582ci Ultra Street engine that pumps out 745 hp at 6,200 rpm and 710 lb-ft of torque at a mere 4,500. This is a monstrous 4.600-inch bore and long-arm 4.375-inch stroke, so even with a big Comp Cams or Crane mechanical-roller cam that specs at 260/266 degrees of duration at 0.050-inch tappet lift with 0.668/0.678 inches of lift with a 114-degree lobe-separation angle, this motor can still make the power on pump gas with 10.5:1 compression. Horsepower and torque numbers on these gargantuan motors are all dyno'd with a 1,050-cfm Dominator carb. According to Shafiroff's guys, the biggest complaint after the buyer stuffs the motor into his car is that the rear tires shred in record time. Of course, if you really want to go crazy, Shafiroff also sells a tall-deck 598ci package that makes 755 hp at a mere 6,000 rpm. Lord have mercy.

Shafiroff Race Engines
Bohemia, NY
800/295-7142
shafiroff.com

Butler Performance can build... 

   

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Butler Performance can build complete Pontiac crate engines between 400 ci and 600 ci-it all depends on how big and how much grunt you want to put to the ground. Its pump-gas 467ci stroker can thump out 550 hp, depending on cam timing.

Pontiac 467 CI
The desirable Pontiac 455 blocks are becoming so hard to find that the big move now is to stuff a 4.250-inch-stroke aftermarket crank into a 400 block. Butler Performance knows all about this and has several options for the aspiring Pontiac power-monger. The company offers a stroker-crank rotating assembly that includes a cast crank, 6.800-inch H-beam rods, and a set of Ross forged pistons for a reasonable price. You can purchase an assembled short-block, or you can commission Butler Performance to build the complete engine, which includes blueprinting. According to owner Jim Butler, the 461/467ci package will easily make 530 to 550 hp depending upon the camshaft selection. The most popular and streetable choice is the Comp Cams Xtreme Energy 274 hydraulic flat-tappet cam that specs out at 230/236 degrees of duration at 0.050 inch along with 0.488/0.491 inches of lift using a 1.5:1 rocker ratio. For cylinder heads, Butler recommends a set of BP-ported-and-assembled Edelbrock heads complete with 2.11/1.77-inch valves, polished chambers, and 10-degree locks and retainers. Cap that off with an Edelbrock Performer RPM intake and a Holley 850-cfm carburetor along with a set of Doug's 1 7/8-inch headers.

Butler Performance
Leoma, TN
931/762-4596
butlerperformance.com

Building a 406ci Pontiac is... 

   

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Building a 406ci Pontiac is actually pretty easy and far more affordable than a 455.

Pontiac 400 CI
Let's face it: Not every Pontiac guy is into 600hp stroker motors. Some just want to have fun with a torquey street engine. For the money, the 400 is the way to go, so we called Ken Crocie at H-O Enterprises to get his take on a good-running Pontiac. The 400 is just an over-bored 389, so the stock 4.12-inch bore can be easily punched to 4.15 with a set of Speed-Pro forged flat-top pistons to make 406 inches. The Edelbrock Pontiac Performer RPM heads are the way to go with 2.11/1.66-inch valves and 72cc chambers to make an honest 10:1 compression. Crocie did warn us that these heads require Ram Air IV-style round-port headers that are generally more expensive. The more plentiful D-port Pontiac headers won't work with the Edelbrock heads. Among the stock-iron heads, Crocie recommends the 64 casting number '70 455 iron head as the best production piece, but he says in stock condition these heads give up a bunch of power to the Edelbrocks. As for a cam, Crocie spec'd a Crane 296 PowerMax flat-tappet hydraulic with 234/242 degrees of duration at 0.050-inch along with 0.473/0.488 inches of valve lift. Combined with an Edelbrock Performer RPM intake and a 750-cfm carburetor, you're looking at roughly 440 hp and 460 lb-ft of torque.

H-O Enterprises
Rancho Cucamonga, CA
909/980-1451
hoenterprises.com