What We Did
Give an old-school 355ci a new look and a lot more power
We gained 111 hp and 600 rpm on the dyno with a simple top-end kit
Mystery engines are always more entertaining than their crate/off-the-shelf brethren; not knowing what's on the inside can make them more or less interesting real fast. Our mystery motor could have high-compression pistons with forged internals ... or it could have a less-than-willing stock bottom end with a set of beat-up main bearings-it's just part of the deal when getting into a running car or engine secondhand. Originally, this little goose sat between the framerails of a second-gen Camaro, Henry D's project F73, to be exact. And as most of you know, we pulled this old slug from the car to perform a perfect summer makeover and also to give us as much room as possible for the chassis to be retrofitted with an all-new Detroit Speed suspension.
Considering our little mill was in perfect running order before we pulled it, we couldn't think of a better way to showcase its power potential than with a complete makeover-all of which would only call for bolt-ons while leaving the bottom end alone. We wanted to keep the costs down and keep the work performed to a minimum. The 355 featured a set of vintage cast-iron Corvette heads, a leaky oil pan, a stamped timing cover, and an older dual-plane manifold. Not exactly modern, but a solid performer nonetheless.
We outlined this build with a few basic rules: increase breathing with airflow, supply ample fuel, and maximize the power for the street. The major makeover components consisted of a set of heavy-puffing aluminum CNC-ported Brodix heads, single plane manifold, and a Comp valvetrain. While our unkown cam was pulled, we relied on a high-lift 0.520/0.540-inch intake/exhaust with 236/242 degrees of duration at 0.050-inch. It all sat on 110 degrees of lobe separation.
Topping it off is a gasket-matched SP1 single-plane manifold, also from Brodix. For good measure, we replaced our oiling system with all Moroso pieces, including a high-volume oil pump and pickup, and a deeper sump pan with screen. To maintain our street creed, we upgraded the fuel delivery with a 750-cfm Quick Fuel Technology carburetor and placed our confidence in a drop-in, ready-to-go MSD distributor.
We enlisted Westech Performance Center in Mira Loma, California, to get us baseline numbers from the original setup. With numbers in hand, we tore down the small-block and took care of its aging looks with a fresh coat of Chevy Orange paint.
Was it worth the effort? Considering it took all of two days-one for the teardown and rebuild and another spent on the dyno-111 additional ponies was well worth it, almost too easy to be honest. Tag along to see how we did it and how to do your own small-block makeover.