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Car Craft Engine Build & Comparison - Battle of the Titans: Chevy 350

Photography by Terry McGean

With the crank cleaned and the rods weight-matched, the pistons, pins, and rings were weighed to verify that they also matched as promised on the Speed Pro box (they did) and then the crank was assembled with bob weights on the spin-balance rig. This is an expense that is usually considered optional, though since we were changing the rods as well as the pistons, we felt it was necessary. If you're building a performance engine, spend the extra cash for the balance job.

Once the rotating assembly was balanced, JMS hung the pistons on the rods and it was finally time to start putting it all together. Out of the three Titan engines, the Chevy was obviously the easiest to build on a budget, which left us with a few bucks for accessories. One of the extras we sprang for was a Milodon windage tray, which necessitated a special main-stud kit, also purchased from Milodon. After the crank was set in place, the studs were threaded in by hand, and then the caps were installed and torqued. As a bonus, the stud kit will also provide extra strength to our bottom end. The improved oil control offered by the windage tray should add a few more ponies too.

Once JMS buttoned up the bottom end, we moved to the all-important camshaft. Since we were limited to hydraulic flat-tappet cams by the rules of the competition, we selected one of Crane's Saturday Night Special grinds to make big torque and horsepower in the upper-rpm range. The shaft is ground for 244/252 degrees duration at 0.050-inch lift and 0.516/0.525-inch lift on a 106-degree lobe separation angle. We checked it with a degree wheel to verify its placement and briefly considered advancing it to further boost low-end torque (our Cloyes timing set allowed 4 degrees). Upon further inspection of the specs, however, we decided to merely install it straight up as Crane intended.

The plan called for Vortec heads, but there was a potential flaw with that approach. From the factory, the Vortecs can only handle a maximum of 0.470-inch lift without bottoming the valvespring retainers against the tops of the valveguide seals. In addition, the factory springs were not designed for high-lift or long-duration lobe profiles, which we fully intended to use. These issues can be dealt with by having a machine shop machine the valveguides and install better springs, but we found the simpler solution was to purchase upgraded heads from Scoggin-Dickey Parts Center in Lubbock, Texas. Scoggin-Dickey offers its own version of the Vortec with Z28 valvesprings and LT4 retainers, which are both lighter (to improve rpm capability) and shallower (to provide extra retainer-to-guide clearance). We had JMS verify the claims, and as promised, the heads were good for 0.525-inch lift.

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