Of course, just because it looks like a 383 on the outside doesn't mean it had to be one on the inside. Muscle Motors (MM) of Lansing, Michigan, is well-known in the business for its stroker kits, and we chose their 431 kit for our project (MM also offers a 496 kit for the 383). The balanced rotating kit includes Ross forged pistons, Childs & Albert rings, I-beam connecting rods, Clevite 77 bearings, and a 4340 chromoly steel crankshaft with a 3.75-inch stroke, which is a stock stroke on a 440. This crankshaft has 383 size mains, so there's no need to cut an old 440 crankshaft's mains to size or to bore and hone the main caps to the 440 size. The resulting strong-arm tactics should help this motor produce tons of torque for this heavy B-car. Muscle Motors has built a great reputation with its quality stroker kits, and we saw first-hand why. This was all top-shelf hardware.
For a cam, we selected a Crane Cams HR-230 grind, featuring .528/.539-inch lift and 230/236-degrees duration at .050 inch, with a lobe separation angle (LSA) of 112 degrees. We chose this hydraulic roller stick with its similar duration profile (that was in the 383) for a decent idle and street manners. Being a roller, it'll optimize the torque and power output from the added cubes and better breathing heads. Crane also supplied us with their high-quality roller rockers with a 1.5 ratio. We could have used Crane's 1.6 rockers to bring the total valve lift to roughly .560/.570, but we stuck with the 1.5s to ensure long valvetrain life.
When choosing cylinder heads, we went with Edelbrock aluminum castings (PN 60929). But we didn't leave them stock. Foley did his usual porting job, which was then flow benched by Wayne Williams at Cylinder Head Service in Seaville, New Jersey (presently closed for business). The Edelbrock Performer heads are fine pieces in stock trim and come with 2.14-inch intake valves and 1.81-inch on the exhaust, but we were able to improve their flow dramatically. Stock, the intake ports flowed 284 cfm at .600-inch lift, and the exhaust flowed 213 cfm. After porting, the intake side showed 301 cfm, and the exhaust handled 227 cfm at .600 lift. Equally important (and often overlooked), after back-cutting the intake valves, the low lift numbers (.200-, .300-, and .400-inch lift) increased by 8, 10, and 4 cfm, respectively (see flow charts).
We've had great success in the past strip-testing with Edelbrock's Performer RPM intake, and we decided to use one in this application. We worked some magic on this piece as well. Concentrating on the plenum area, runner entrances and exits, along with polishing the inside short turns on the numbers 5 and 7 ports, would add velocity to the mix. For a carburetor, we're going with the proven Holley 950HP to match our expected power potential.
To keep our stroker properly lubricated, we chose a new MP pump and larger capacity oil pan (7 quart) with a windage tray from Milodon. We'll break it in with conventional motor oil before switching over to full synthetic oil. We decided to try Quaker State Q Racing oil once we get it to the track.
When it comes to the parts that put it together, we look to Summit for those necessities. Summit supplied us with the ARP fasteners (main studs, head bolts, and engine accessory kit), Mopar Performance goodies (aluminum W/P housing, chrome timing cover, HV oil pump, oil filters, engine small parts kit, and crankshaft bolt), FelPro gaskets, and a Powermaster mini-starter. We felt Summit's no-name chrome valve covers would be a nice touch for the new motor. The internally balanced engine assembly (by Muscle Motors) would need a new high-quality harmonic balancer. We choose to use a proven damper-a Summit brand SFI-approved unit. These are just some of those gotta-have parts you need to assemble an engine.