Mike Mavrigian, tech editor for Hotrod & Restoration, recently began his latest engine build—a bored and stroked Pontiac 455 engine at his Creston, Ohio-based shop, Birchwood Automotive Group.

“The direction of this build is to start with an OEM Pontiac 455 block, bore and stroke to 501 CID, and build an approximately 600-horsepower street performer,” Mavrigian wrote on his Precision Engine website. “The target audience [is] the street/strip muscle car and/or street rodder application.”

In the first part of the build, Mavrigian smoothed out the block exterior to obtain a show-quality surface finish. Later, he’ll paint the block in the original Pontiac blue metallic.

Next, Mavrigian spent a few days dressing the block exterior, grinding off any casting nubs, radiusing sharp edges and smoothing out all exterior surfaces using a combination of tools and methods that included carbide cutting bits on a high-speed die grinder and angled pneumatic die grinders. Any low spots (due to the irregular casting surfaces) were filled with small amounts of All-Metal body filler.

After servicing the block, Mavrigian took it to Ross Racing Engines, where Tony Lombardi installed the new set of ARP main cap studs and carefully torqued all main cap locations.

To read the entire article and see all of the modifications Mavrigian made to the block during Part 1 of the build, click here.

Tags: Birchwood Automotive Group, Engine Builders, Engines, Mike Mavrigian, Precision Engine