Completed 408HP 327CI Engine.

Tim Moore started this buildup with a set of Keith Black hypereutectic pistons that set the compression at a very streetable 9.1:1. The KB pistons allowed Moore to run a fairly tight piston-to-wall clearance for quiet street operation.

The key to this stout 331-inch Mouse is the Comp Cams hydraulic-roller cam and kit. This is the retrofit K-kit that comes with the cam, lifters, pushrods, springs, retainers, keepers, timing set, and a nylon cam button.

Moore ground the stock steel small-journal 327 crank and rebuilt the rods using ARP rod bolts. Here he uses an ARP rod bolt stretch gauge to accurately torque the rods to the spec of 0.006 inch of bolt stretch. This is the only right way to torque rod bolts.

Proper installation of the roller cam requires a cam button to prevent cam walk, which retards the ignition timing. The button uses several washers to set the proper end clearance.

Moore set the thrust clearance at 0.005 inch using a dial indicator on the cam at the back of the block with the timing chain cover and water pump thrust bolt installed on the front.

The retrofit Comp Cams hydraulic-roller lifters come with tie-bars that prevent the lifters from rotating in the bore. These also require shorter pushrods because of the taller lifter body. On the right is a stock replacement hydraulic-roller lifter for 87-and-later small-blocks.

Moore retained the original iron 461 heads but had Slover's Porting Service tune them up with a mild pocket-porting effort. Moore used Manley Street-Flo stainless steel 2.02/1.60-inch valves to complete the job.

Moore selected the Edelbrock Performer RPM because it's worth some power and looks like the factory dual-plane. The carb is an original Chevy 780 vacuum-secondary unit that Moore rebuilt.

Moore Auto sells a special heavy-duty alternator mount (arrow) that bolts to the header and uses the stock alternator bracket.

The headers are DynoMax ceramic-coated headers. The black Moroso Blue Max wires look almost stock but are much better.

We took this little 331ci small-block out to Westech Performance, bolted it on the Super Flow dyno, and surprised everyone with a solid 408 hp at 5,700 rpm and 400 lb-ft at 4,800 rpm.

Not only did Moore machine the heads for larger-diameter springs, but he also added ARP screw-in studs, Manley valves and guideplates, and a set of Comp Cams Pro Magnum roller 1.52 rockers.