Chevy Corvette 350 Engine - One-Stop Topping

With Help From TFS, We Make 428HP From An Old 350-And It's 87-Octane Friendly.

Dan Ryder Nov 1, 2008 0 Comment(s)
Sucp_0811_21_z Chevy_corvette_350_engine Timing_cover 1/29

As we tried to install the ProForm timing cover, a problem was encountered. The design of the cover was not compliant for use with a roller camshaft utilizing a cam button (something to keep in mind). It was then time to pull the stock unit from the pile of old parts and clean it up for use. Sometimes functionality takes precedence over looks. We laid the cylinder head gaskets on our previously cleaned block surface. All gaskets are included with the TFS package.

All rockers were properly adjusted as per the instructions and the Edelbrock RPM Air-Gap intake manifold was installed. The Edelbrock unit is a dual-plane design and will offer a better idle quality, as well as low-end grunt compared to a single plane unit. While a single-plane unit might have given us a better horsepower number, we're looking for the total package.

Now came time to lay the 195cc TFS 23-degree cylinder heads atop our assembled short-block. These TFS heads come with 64cc chambers. The valves measure 2.02-inches (intake) and 1.60 (exhaust). Included in the package is a set of ARP cylinder head bolts, known for their reliability and strength. We torqued the bolts according to the sequence provided by TFS in three stages: 32 lb-ft, 52 lb-ft and 70 lb-ft.

The TFS package comes with a complete set of instructions, including torque specifications and patterns. Once the cylinder heads were torqued, we installed the newly designed TFS hydraulic tie-bar style lifters (not included). A tie-bar style lifter is necessary because older engine blocks didn't have provisions for a roller type camshaft. The TFS units fit perfectly with no binding.

It's time to install the guide plates and rocker studs to the cylinder heads. We measured for proper pushrod length, using the length tester in the kit. The stock pushrod (7.750-inches) was used on the valve stem to the right and the new TFS hardened piece (7.250-inches) on the left. As you can see, the pattern on the left shows the rocker tip riding within the middle portion of the valve stem tip, and the valve stem tip on the right, toward the bottom. Always check this by temporarily installing a pushrod length checker, along with the rocker, and rotating the engine one revolution. Adjust the length checker as needed to seat the rocker fulcrum toward the middle of the stem. Finally we installed the CNC-machined TFS 1.5 ratio roller rockers to actuate the valves in a controlled manner (pushrods not included).