C4 Top-End Upgrades - A Plan Comes Together

Pulling off the front cover exposes the factory timing chain.

Once that's been removed, out comes the stock cam.

The next steps involve installing our TFS cam, followed by the GMPP Severe Duty timing set...

...and freshly cleaned front cover.

Now that the front of the engine is back together, it's time to pull the factory LT1 cylinder heads.

After laying the included gaskets in place, Lovell installs the new Fast as Cast GenX heads.

They're secured with beefy ARP bolts, which also come with the TFS package.

Lovell then drops in our fresh TFS lifters...

...and reinstalls the factory lifter-retaining hardware.

Adding oil directly into the lifter valley (rather than via the fill tube) effectively "pre-oils" the engine, allowing lubricant to coat critical engine parts as it drains into the pan. We used Royal Purple 10W-30 synthetic.

The remainder of the job involves installing any remaining engine parts, including, in our case, a set of TFS 1.6-ratio roller rockers...

...and the included 30-lb/hr fuel injectors.

This shot of the completed engine provides little evidence of the work that's taken place. Cowl-mounted bottle caps add critical car-guy cred.

Like any major engine modification, the TFS package requires custom, post-install PCM tuning to achieve an optimum balance of performance and driveability. We sent our car's computer off to Tony Gonyon (shown), at TunersInc. in Orange Park, Florida, who has extensive experience with the late C4's complex OBD-II brain. Once the recalibrated unit arrives back at VETTE HQ, we'll be ready to perform our usual battery of dyno and track testing.