Here you can get a good view of the business side of the Weisco pistons provided by Lunati. The -15cc dish will yield us a very pump gas-friendly 10:1 compression ratio.
With the Fel-Pro gasket in place, the RHS cylinder head was carefully lowered into position. Once in place, it was secured using ARP bolts liberally swathed in assembly lube.
The only downside to running the sexy shaft-mounted rockers was that the factory valve covers would no longer fit. Luckily Turn Key had these sweet billet spacers on hand to save the day. They incorporate the same gasket as the GM valve covers, so they're easy to install and will be leak-free.
With the Weiand intake, GM fuel rails, 46-pound injectors, and coil packs installed, our 427 small-block is ready for its date with the dyno at Westech Performance.
Given how bulletproof the rest of our engine was, we didn't want to cheap-out on the rockers, so we went with Comp's shaft-mounted aluminum units (PN1500). These rockers feature 8629 steel pedestals with shafts that have been deep case-hardened and tempered for max strength. The benefit of the shaft arrangement is that it provides a stable and accurate pivot point for the 2024 aluminum 1.7-ratio rocker arm bodies. They also feature oil passages that feed pressurized oil to the shaft bearings and rollers tips. This not only extends the service life, but it provides a continuous stream of cooling oil to the valve springs.
Another issue arose when we went to bolt the Weiand aluminum intake on top of the LS2 valley cover. The Weiand intake has been around for a few years, and General Motors has revised its valley covers to incorporate bungs for PCV fittings. We could have cut these offending bumps off the LS2 cover and welded up the holes, but Turn Key had an easier solution in the form of this flat billet valley cover that it typically uses when installing blowers. Before the '69 Camaro is finished, we will be swapping out the aluminum intake for Weiand's new 90mm composite Street Warrior intake.
Here are the brains of this operation, a GM MEFI-4 computer. It's small, but more than capable of controlling our new 427 powerplant. Turn Key also provided its five-wire hookup engine harness. Just as the name implies, this simple-to-install harness requires only five wires to be spliced into the rest of the car. This is a good thing, since time is running out to get this project on the road, and the guys at Route 66 Motorsports will appreciate the simplicity when they graft this engine into the Camaro.
With the 427 strapped down to Westech's Superflow 901 dyno, Kory could get started tuning the all-aluminum engine. Running on the 91-octane stuff they pass off in California as premium gas, the mill put down peak numbers of 562 hp at 6,200 rpm and 561 lb-ft or torque at 4,700 rpm. More important, the torque curve of the engine extends past 450 lb-ft from 3,000 rpm all the way through 6,400 rpm, and at idle it runs silky smooth.