Thread: 283 with small journal 327 crank

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It's tough to find affordable pistons that will yield 11.0:1 in a 292 with decent heads. Here's what I came up with just foolin' around on the DynoSim.
283 bored 0.060"
Keith Black hypers, KB166-060
L31 Vortec heads, cut 0.040" for 58cc chambers. Stock 1.94/1.50 valves, springs and retainers matched to lift. Makes static compression ratio of 10.5:1. Heads are bone-stock except for springs and retainers and the 0.040" cut. You can rescue 'em out of a boneyard. Casting number 12558062 in a '96-'98 Chevy truck with 5700 Vortec motor. Look for a saw-tooth design on the front of the heads. Get the rail rockers and center bolt valve covers at the same time you're gettin' the heads.
CompCams solid flat tappet cam. 12-221-5, grind 280B-8, 280/285, 242/250, 507/532, 108.
Large tube stepped race headers
Edelbrock RPM Vortec intake w/750 carb
RPM HP TQ
3000 201 252
3500 253 380
4000 312 410
4500 372 434
5000 424 446
5500 457 436
6000 489 428
6500 502 406
7000 507 380
7500 505 354
8000 495 325
136 mph top speed @8000 w/4.88 gear, 28" tire. Use 3000+ stall converter with auto. Would be way more fun with a 4-spd/5-spd. I realize the original poster asked for a way to enlarge his 283 to pull a truck. This is not the motor to do that. This is a play-toy built the way Scooter might do it. I just wanted to dyno it and see what it looked like. Who says you can't make 500 hp out of a budget 283??? A guy might have to massage the domes a little to fit the chambers, but you'd still make 500 hp even if you dropped the SCR a couple of tenths. Disable the centrifugal and vacuum advance and lock it up at 34-36 degrees. Install a switch through a relay to disable the ignition while cranking, then flip the switch to ignition-on while the motor's spinnin'.