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Turbo Pontiac 400 Build - Ludicrous Pontiac Power

Ken Crocie Built A 489ci Stroker Pontiac Pressurized With A Single Turbo And A Q-Jet That Is A Recipe For Ludicrous Power

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It doesn't take long when reading car magazines to realize how each story always comes off looking easy. Even if the tale is all about trial and frustration, it can seem like another chapter out of Aesop's Fables. That's because the reader is always spared the fits and starts, and the story takes barely 30 minutes to read. The only thing more fantastic than a quick magazine story is a complete muscle car buildup in 42 minutes on reality TV. So when we tell you Ken Crocie spent months on this turbo Pontiac restoration and all but slept at Westech's shop in search of respectable Pontiac power, it was all in the name of doing the project justice. We came along for the ride as intrigued observers, but trust us-the suffering was all Crocie's.

Pontiac true believers will recognize Crocie's name as the man behind H-O Enterprises and its 30-plus-year Pontiac approach to performance engines and suspension goodies. If you spoke Pontiac back in the '70s and '80s, he was the man in the guru chair. One accomplishment that was way ahead of its time was a single blow-through turbocharger kit that guaranteed to double the horsepower on any 350ci to 455ci turbo Pontiac. Crocie and then H-O owner Craig Hendrickson designed and built a kit that produced single-digit boost numbers and pushed that boost through an unlikely Q-jet carb. A few of these kits ended up in Mecum Macho T/A Pontiac Firebirds, which brings us up to the 21st century when a Crocie customer desired an upgraded stroker big-block Pontiac fitted to his original H-O turbo kit. The plan was to make the turbo Pontiac package look original on the outside yet breathe as much fire as possible.

Pontiacs are big on torque, and Crocie decided to capitalize on this by upping the displacement on a middle-child 400ci motor with a stroker crank that created what Crocie calls a 488 (it actually calcs out at 489, but who's counting?). Before going any further, Crocie emphasized that this was a restoration project, not the typical hunt for maximum horsepower. The goal was a restofied Trans Am that should look just like one of those Mecum machines from the early '80s-along with a carefully placed wink and a nudge.

Turbo Pontiac: The Engine
Crocie started with a basic Pontiac block that he immediately punched with a 0.040-inch-larger bore and added a 3/4-inch-longer Scat 4.50-inch crank to replace the stock 3.75-inch piece along with Scat forged 6.700- inch-long H-beam rods. This created a 489ci monster to which he added a Probe piston with a generous dish to keep the compression at around 8.3:1. The plan was to allow the turbocharger to make up for the low static compression. Since the engine would be street driven and turbochargers tend to respond to short-duration camshafts with wide lobe-separation angles, Crocie spec'd a custom Comp Cams hydraulic roller using the XFI lobe design. This lobe was created to generate maximum lift from a relatively short duration that he combined with the Comp 1.5:1 roller rockers. All the machine work was performed by Outlaw Racing.

Because this was a resto of sorts, Crocie had to retain the iron Pontiac 6X heads that got the bigger 2.11/1.77-inch valves upgraded to a set of stainless SI versions along with better springs and retainers after Tim Martindale of Outlaw Racing Engines did the porting work. Crocie then topped the whole package off with an Edelbrock Performer (yes, that's right) dual-plane intake that had to be used because of hood clearance issues. Of course, that choice wasn't nearly as restrictive as the original factory exhaust manifolds. But as you will see, even with these limitations, this Pontiac compensates quite nicely.

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