If you've been following our little engine shootout series, then you're already familiar with our self-imposed guidelines for the building of the three Battle of the Titans engines. As a refresher, the small-blocks must not exceed 365 ci, and they must run on pump gas, be equipped with a hydraulic flat-tappet cam, and use production iron cylinder heads. Those heads can't be messed with, and the whole deal has to be topped with a dual-plane intake. Oh, and then there's the budget--$2,500, including machine work, though the cost of the core parts (block, crank, and so on) doesn't have to be included on the balance sheet. The carb, ignition, and headers are considered ancillary items that will be supplied for the test so they are not included in the price. The carb is a Demon 750-cfm unit, which will be shared by all the engines, and the headers were agreed to be full-length 15/8-inch tubes, this time from Hooker.
The stories on the Mopar 360 and Ford 351W have already run in these pages in the preceding issues, leaving the Mouse motor as the final buildup before we get to our dyno shootout next month. Onlookers who can remain at least somewhat impartial will no doubt assume that the Chevy has the advantage, since the most stifling element of the rules is certainly the bit about unported factory castings.
Unless you've been under a rock for the past few years, you know of GM's Vortec heads, designed for use on light trucks and put into production with the '96 model year. The factory was looking for increased efficiency, but of course, where there's efficiency, there's usually more power. The aftermarket caught on pretty quickly and Edelbrock took care of the one major hurdle to mounting these heads on your typical carbureted small-block by building a series of intake manifolds specifically for the unique Vortec intake manifold mounting arrangement.
What many people don't realize is that Ford also has it's own version of the small-block high-velocity/fast-burn-style head, dubbed the GT-40P. It too was designed for light trucks, specifically, the V-8-powered Explorers from the '97 until the end of the 5.0 pushrod V-8. That leaves the Chrysler, but don't sell the Mopar short. With factory-engineered 18-degree valve angles and relatively big valves (2.02/1.60) combined with the longest stroke of the shootout (3.58 inches) and the longest connecting rod (6.123 inches), it isn't exactly handicapped.
But those are bench-racing topics ripe for excuses after dyno day is done and after the dust has settled to the dyno-cell floor. For that, you'll have to tune in again next month, though we'll mention that two of the three engines have already run, and the results were not as predicted. The Chevy can still clean house--or fail miserably. We figured out our combination and took the accumulated parts and pieces to JMS Racing Engines in Monrovia, California, the same facility that machined the Ford and the Mopar and dyno'd all three engines.
JMS has been around for nearly 30 years and has spent a good portion of that time building engines for various forms of competition, from the drags, to circle tracks, to the Salt Flats, and even the water. The experienced staff (many of whom are racers themselves) was invaluable in ensuring that our cobblings on paper could actually be turned into reality without creating expensive shrapnel. Check out the details of the buildup and stick with us next month when we put all three engines to the crucible test of the engine dyno.