Our bang-for-the-buck mentality can lend to a host of great ideas and combustive mixtures for making super power on short coin. Don't get us wrong--we love a great custom engine combination making freight-train steam that sends the earth's rotation twisting in the other direction. However, we also still have an affinity for proven short-block combination builds. For the street, our theory for boxed engines has yet to be questioned.

It was important to begin our build on solid ground. GM Performance Parts (GMPP) might as well be called Engines "R" Us, because its catalog is basically a toy store for the itchy automotive soul. Our insatiable appetite for GMPP's ready-to-go short-blocks made the company an easy choice for cost-effective power. The offerings range from sedate two-bolt main 290hp 350s and more muscular and complete 383 turnkey engines to the baddest of the bad, such as the 720hp 572ci big-block. Now, we can't help but get our hands dirty, and the 383 carries the best of both worlds for the street. While we appreciate GM's willingness for drop-in-style turnkey motors with all the bells and whistles, we also wanted to take full advantage of Brodix's new top-end kit.

There we opted for the 383 short-block crate engine (PN 12499106) for a solid foundation. This assembly features a four-bolt main with a one-piece rear main seal, the perfect starting point for solid, reliable power in a box. Inside resides a forged 4340 steel 3.800-inch stroker crankshaft, heavy-duty 5.700-inch connecting rods, and hypereutectic dished pistons--needing only a valvetrain and top end to complete the engine.

For just about $1,950, Brodix will pull out complete matching aluminum 200cc intake runner cylinder heads and a dual-plane manifold combo unlike any other. While the heads come standard with 64cc chambers, we had Brodix mill them to 58 cc (additional $212), bumping the compression ratio. We also took advantage of the CNC combustion chambers option, which added $227 to the tab. Even at 58 cc, pump gas is still a reality with this kit, plus Brodix makes sure to supply everything needed to button up the top end.

What's more is our Comp valvetrain took full advantage of the Brodix package. The Comp 'stick we chose came with 242/248 degrees of duration at 0.050 and 0.540/0.562 inch lift on intake/exhaust. We even topped the valvetrain off with Comp's newest member, the Ultra-Pro Magnum roller rockers with a 1.52:1 ratio.

As usual, we followed the build at Westech Performace Group, as Steve Brul put up the wrenching. We threw in the Comp goodies, bolted on the Brodix top end, installed a Holley 750, and strapped the 383 to the dyno to get the numbers all in one day. Our combo was good for 466 hp and 456 lb-ft, and we even ran the mill to 7,000 rpm to showcase its upper-rpm potential. Read on to see how we pulled it off.

Quick Notes
What We Did
Pieced together a reliable yet potent 383 combo for the street

Bottom Line
It's a stump-puller from 3,000 rpm on up

Cost (Approx)
$2,400 for top end, $6,035 bottom end

GMPP 383CI
1. Brodix dual-plane manifold with 4150 carb base fitted with Holley 750-cfm carburetor. Kansas-like torque curves for everyday grunt and upper-rpm flexibility were abundant.
2. The camshaft took advantage of the Brodix 200cc heads. We swapped out the springs, locks, and retainers to avoid valve float and to increase our rev potential. We swapped in Comp springs (PN 26120), locks (PN 795-16), and retainers (PN 613-19) for more open/closed seat pressure.
3. Comp 7.300-inch-long pushrods (PN 7949-16) push the Comp hydraulic rollers we have in place with H-bars. The pushrods are heat-treated chromoly with 0.080-inch wall thickness.
4. As usual, we relied on a Pro-Billet MSD ignition distributor (PN 85551) and wires.
5. Expelling fumes were Hedman 1 3/4 x 3 1/2-inch dyno headers with 18-inch collectors.

THE PROOF
Compression ratio 9.75:1
Fuel 91-octane
Timing 37 degrees
Spacer Wilson tapered
4-hole combo
Max torque (lb-ft) 456 @ 5,100 rpm
Max power (hp) 466 @ 6,500 rpm
Avg. torque (lb-ft) 424
Avg. power (hp) 382
RPM LB-FT CHP
3000 389 222
3100 387 229
3200 390 237
3300 397 249
3400 408 263
3500 415 277
3600 422 289
3700 427 301
3800 432 313
3900 437 325
4000 440 335
4100 442 345
4200 445 356
4300 447 366
4400 449 376
4500 449 384
4600 448 392
4700 447 400
4800 446 408
4900 447 417
5000 447 426
5100 456 433
5200 442 438
5300 440 444
5400 436 449
5500 433 453
5600 429 457
5700 424 460
5800 419 462
5900 414 465
6000 408 466
6100 400 465
6200 394 465
6300 388 464
6400 382 465
6500 376 466

Build List
Our foundation was a GM 383 short-block assembly (four-bolt main block, forged crankshaft, hypereutectic pistons, 5.700-inch rods, 8-inch harmonic balancer, 12 3/4-inch flexplate, windage tray, 5-quart oil pan, composite timing cover).

The top-end kit included 200cc cylinder heads, clean and blended bowls, CNC combustion chamber, angle milling for increased compression, matched intake ports, 2.20/1.600-inch intake/exhaust valves, dual-plane intake manifold, valve covers, intake gasket, 4150 carb gasket, STD port exhaust gasket, NGK B8ES spark plugs, head bolt kit, intake manifold bolt kit.

MFG DESCRIPTION PN PRICE
GMPP Short-block assembly 12499106 $3,500
BRODIX Top-end kit 9991010 2,400
ADDITIONAL ITEMS
COMP CAMS Hydraulic roller camshaft CS XR294HR-10 12-443-8 266
Hydraulic roller lifters 875-16 223
Hardware kit 08-1000 121
Ultra-Pro Magnum roller rockers 1601-16 324
Pushrods 7949-16 135
Beehive springs 26120-16 120
10 steel retainers 795-16 56
10 11/32-inch locks 613-16 24
HOLLEY 750-cfm 4150HP carburetor 0-82750 526
MSD Pro-billet distributor 85551 228
TCI Rattler Balancer 870003 384
WILSON 4-hole tapered combo aluminum spacer plate 004110 128
SERVICES
WESTECH Full engine dyno, tune and fuel   600
TOTAL $9,035
SOURCE
TCI
Ashland
MS
662-224-8972
www.tciauto.com
Brodix
301 Maple P.O. Box 1347
Mena
AR  71953
Wilson
N/A
wilsonmanifolds.com
MSD
El Paso
TX  79936
915-857-5200
www.msdignition.com
GM Performance Parts
www.gmperformanceparts.com
Westech Performance Group
11098 Venture Dr., Unit C
Mira Loma
CA  91752
9-09/-685-4767
www.westechperformance.com
COMP
Memphis
TN
compcams.com
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