One of the last things to do during preliminary mock-up is to check the valve-to-piston clearances. A set of lightweight "checking springs" were installed on the cylinder head for the #1 cylinder location. Next, the chamber, the valve faces, and the piston dome were given a light coat of oil and two small portions of modeling clay were pressed into place in the radii of the valve reliefs.

The cylinder head was placed directly on the block (sans head gasket) and two cylinder head bolts were snugged down to keep everything in place. Next, a pair of lifters, pushrods and rocker arms were installed and the valve lash was set to zero. The crankshaft was then carefully rotated two full turns to run the valve train through a complete cycle. The valvetrain components were removed followed by the cylinder head. The compressed clay sections were carefully measured to check for both horizontal and radial valve clearance. Given the generous valve reliefs of the SRP pistons and the (relatively) modest camshaft timing, ample valve-to-piston clearance was present.

Once the final mock-up was complete and all clearances were verified, the rotating assembly was sent out for balancing. Prior to the final assembly, everything was cleaned within an inch of its life.

The first component to go into the block was the camshaft. While we're discussing the camshaft, I should mention that I deliberated long and hard before finally deciding on a cam to use for this engine build . Given the rather modest displacement of the engine and the rather generous plenum volume of the intended crossram manifold, I was very concerned with trying to build a respectable amount of low-end torque without sacrificing higher-rpm power.

The factory camshaft for the `69 302 Z28 engine specs out with 254 degrees of duration at .050" on both the intake and the exhaust side with .485" gross lift (.455" net with lash) with a 114 degree LSA and an intake centerline of 112 degrees. If I may be so bold as to state, I consider the 302 Chevrolet engine grossly over-cammed from the factory for a "production passenger car" engine (albeit a thinly disguised race engine at heart), and is one of the main reasons even a stock 302 lacks low-end torque.

Consider this: The 1970 350 cubic inch LT1 engine which replaced the `69 model year 302 was essentially identical to its predecessor save for two things; .480" additional stroke, and a smaller camshaft!

Taking this cue from the General, I chose an off-the-shelf solid lifter camshaft with 10 degrees less intake duration and 2 degrees less exhaust duration than the factory `69 cam.

The camshaft part number and specifications will not be divulged, but I will say that aside from the previously mentioned differences in duration compared to the OEM camshaft, the cam I selected has slightly more lift on both the intake and exhaust side, and there is a significant difference in lobe separation angles and lobe centerlines as well. Again, this was all carefully chosen in an effort to maximize driveability and lower rpm torque without sacrificing excessive upper rpm horsepower.

(Note: The cam I selected mandates the use of tubular exhaust headers. It would not work well at all with OEM iron exhaust manifolds)

There is much more that could be discussed here regarding camshafts, but for the sake of brevity I'll conclude this part by stating that this cam worked out even better than I had anticipated. But you'll just have to finish reading the article to see the final dyno numbers.

No red Taco sauce here, only tried and true Moly paste!

Once the cam was installed, the rest of the shortblock was assembled. Since everything was checked several times during mock-up, the short block went together without any drama.

The last components to go into the lower end of the engine were a Melling M55HV oil pump (the older casting with the thicker neck, not one of the newer lightweight castings!) and a new Melling one-piece hardened oil pump driveshaft. I consider these one-piece shafts a must-have for any kind of a performance build-up. The stock nylon collar is fine for grandma Mirdle's 305 Caprice wagon engine, but it has no place in an engine like this.

Lastly, a new OE replacement oil pickup screen was installed into the pump before the timing cover and the oil pan (again, a correct `69 vintage Z28 unit complete with internal baffling) was bolted into place.