To Be a Rocker Arm and Yet to Roll

My first engine rebuild was accomplished on a shoestring budget. As my income has grown just slightly since 1989, I thought it would be a good time to do things the way I wanted to back in the day.

Roller rockers are absolutely not required to build a 7000 RPM valvetrain, but they’re certainly nice to have. For my intentions I decided to go with the Comp Cams Ultra Pro Magnum cast chromoly steel bodied rockers (249-1605-16). These are designed for a 7/16″ big-block stud. This is no accident – the thicker studs flex less under extreme loads.

Rocker Arms

Rocker Arms

This required replacing the factory 3/8″ studs with some “fancy” ARP 135-7101 pieces. A slight modification to the head portion of the studs would be needed due to the thread inserts in the LT-1’s aluminum heads.

Shortening the studs

Shortening the studs

Switching to non-self-aligning rocker arms required the use of pushrod guideplates to keep the roller tips centered on the valve stems. Trickflow Specialities 30400623-8 is the only drop-in for this application due to the valve spacing, but adjustable plates such as those sold by Alex’s Parts would also work. A slight modification to the plates is required to prevent pushrod binding when using 1.6 rockers.

TFS Guideplates

TFS Guideplates

Lastly, the most critical component of a high-revving valvetrain system is a set of springs capable of keeping the lifters firmly planted on the cam lobes. After extensive research I found Lunati’s 73925K5 kit made specifically for the LT-1 heads fit the bill. This is where the can of worms opened up, and Lloyd Elliott of Elliott’s Portworks came into the picture.

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