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Demon Engines 454 Engine - The Low-Buck 454 Part II

We Get More Power With Cylinder Heads And A Cam Swap on . . .

By Richard Holdener, Photography by Richard Holdener

The phones rang off the hook when we covered the components and dyno testing of the low-buck 454 from Demon Engines in the Oct. '10 issue. Checking in at $2,650 outright (minus carburetor), the low-buck 454 from Demon Engines offered an attractive combination of power and pricing. Bypassing the stock replacement and wrecking yard motors, the mill offered a minimum of 400 hp for just less than three large outright and required no core exchange. Even more impressive was the fact that the 400 hp came with a peak torque reading of 542 lb-ft. In fact, torque production exceeded 500 lb-ft from 2,800 rpm to 4,600 rpm, making this big-block a real thumper and ideal for a variety of different applications, including a performance street machine, a truck, or even an RV. Despite all this motor had going for it, we couldn't help but wonder what it might be like with a few performance upgrades. According to Demon Engines, even with a cast crank and factory rods with a bolt upgrade, the short-block will withstand considerable punishment. No way, you say? Not without a steel crank and forged rods! Check out part three when we add a low-buck turbo kit to the mix-but for now we will concentrate on upgrading the low-bucker with a few simple bolt-ons.

The three most important power producers in any combination are the heads, cam, and intake. A close examination of this engine reveals that upgrading at least two of these components will yield significant dividends. Since it was already blessed with a dual-plane intake from Procomp, we set our sights on replacing the peanut-port heads and mild Xtreme Energy cam. As it turned out, our choice of cylinder heads required replacement of the Procomp intake, but more on that later. First up was the camshaft. Out came the XE268H cam from Comp Cams to make room for a slightly wilder XE284H. Our hope was that the new cam profile would shift the torque curve higher in the rev range, thus producing more peak power. At the same time, we couldn't help but hope that the gains would result in only minimal trade-off in low-speed power.

When it comes to cylinder heads, just about any performance aftermarket head represented a significant step up in flow and power potential compared with the factory truck heads. Ideally suited to the 400 to 450hp level, the peanut-port heads are a significant restriction. They were replaced with a set of Profiler heads from Dr. J's Performance. The Profiler heads offered a number of important upgrades, including lightweight aluminum construction and a significant increase in airflow. Lifting a set of iron big-block heads is no picnic, so it should come as no surprise that replacing them with their aluminum counterparts offers a serious weight reduction. On the all-important power-to-weight scale, less weight is the same as more power. Thus, replacing the iron with aluminum heads offers a power gain irrespective of the additional airflow. Naturally, we did not choose the Profiler heads on weight alone; we were much more interested in their impressive flow figures. The Profiler heads also feature a five-angle valve job, a 5/8-inch-thick deck surface, and 0.250-inch raised exhaust ports. They came with CNC combustion chambers and a valvespring package designed for our sub 0.600-lift hydraulic flat-tappet cam, all for less than $2,000.

By Richard Holdener
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