447 HP Vortec Small-Block Build - Budget Sledgehammer

Cylinder Head Flow

PHR would like to especially thank Shaver Racing Engines for performing the cylinder head flow testing and head assembly for us. Shaver is a dealer for EQ cylinder heads, and offers the Vortec EQ Lightning heads in bare or assembled form with a variety of spring and valve packages. (We suggest you call 310-370-6941, or check out www.shaverengines.com, for more information.) Our heads were assembled with cost-effective Manley budget performance valves (1.94-inch intake and 1.50-inch exhaust), a three-angle valve job, and COMP Beehive springs and retainers. That's all. No additional clean-up or port work was performed. As you can see, flow values for the EQ are better than stock, yet still relatively modest. It just goes to show that for a street engine, the amount of flow is a secondary concern to the quality of flow. Other than a .025-inch mill job to up the compression, our heads were box-stock.

On The Flowbench

Tested At Shaver Racing test depression 28-in. H2O

Budget Vortec 350-Turnkey Crate Motor

Speed-O-Motive helped us build our motor and can build you a near replica of our budget Vortec 350-the only difference will be an upgrade to stainless steel roller rockers, a Pertronix Flame Thrower HEI, and a Holley 750 double-pumper. The price of $5,450 includes assembly, dyno tuning, and free shipping. By comparison, a little shopping will uncover more than a few crate engine packages that cost as much or more and don't deliver the goods like this little number. Keep in mind everything that you are getting, including the carburetor, dyno-tuning, and shipping costs. Figure in the whole package, and this combination is quite a performance value. To find out more about ordering a budget Vortec 350 like this, go to www.speedomotive.com, or call 626-869-0270.

Dyno Results

TESTED AT SPEED-O-MOTIVE
DTS ENGINE DYNO

Our choice in valvetrain was...        read full caption Our choice in valvetrain was a big contributor to the engine's outstanding output. The COMP PN 26918 beehive springs have been well proven in allowing high-rpm performance with hydraulic roller cams. The 1.6:1 ratio COMP Magnum rockers deliver a healthy 0.563-inch lift, a big advantage compared to the 0.528 inch that a stock ratio rocker would provide. The pushrods are just our cleaned-up OEM units.

A Vortec Crosswind intake...        read full caption A Vortec Crosswind intake manifold from Professional Products serves to feed the mixture to the heads. We have found this intake manifold provides very good output in street engines operating under 6,500 rpm.

Sufficient carb capacity should...        read full caption Sufficient carb capacity should never be neglected when looking for performance. Our choice is a Holley 3310 universal vacuum secondary carburetor, an ageless design that offers the flow volume our 350 needs at a price we can afford.

Before getting down to testing,...        read full caption Before getting down to testing, we were impressed with how our engine looked, and much of the credit goes to the Dupli-Color engine enamel covering the exterior. This paint was easy to apply and exhibited excellent coverage on our raw cast iron and steel parts.

We'll admit that we were a...        read full caption We'll admit that we were a little uncertain about how much power our low-budget 350 would put out. We knew the combination held the promise of delivering outstanding numbers, but the lack of really exotic equipment tempered our expectations. As Jake Hairston hooked the small-block to Speed-O-Motive's DTS dyno, there was more than the usual amount of discussion in the dyno cell speculating on "what'll she put out."

Before firing our overhauled...        read full caption Before firing our overhauled 350 mill, the crankcase was filled with Royal Purple 10W30 synthetic motor oil. Royal Purple makes a variety of synthetic lubricants that we have always found to offer a great combination of reduced friction for power and longevity.

The engine fired without any...        read full caption The engine fired without any undue drama, and Jake went to work with the base settings, adjusting the ignition timing at 34 degrees total timing by the end of the session.

After a few preliminary short...        read full caption After a few preliminary short pulls to check the mixture readings via a pair of wide-band Lambda sensors, we attempted some high-rpm pulls and were disappointed by a premature drop-off in the power curve. Jake suspected the ignition was falling off at high rpm, and replaced the HEI module in the Summit-sourced HEI with a Performance Distributors Dyna-Mod.