As the old saying goes, "The end of one man's garage space is the start of another man's project." OK, we made that up. Nevertheless, it's true for so many of us-we tenaciously hang onto parts or engines or even entire cars, certain that sometime in the future we'll actually make something of our cache of go-fast goodies. Often, however, that future happens for the next guy-the one who gets a smokin' deal when all that stuff just finally has to go. In this case, the treasure to be had was a complete LS1 engine with a spun bearing, minus coil packs, available for a ridiculously low $250 when the previous owner just had to get it out of his garage. You can be sure we'll be putting this bargain find to good use, starting with its re-creation by Turn Key Engine Supply into a stout-and carbureted-383 stroker.

The decision to add some capacity to this LS1 ended up being something of a no-brainer. The motor had to come apart, and the damage caused by the spun bearing was severe enough to require a new crankshaft. Therefore it made sense to increase the stroke and add some displacement to our Gen III creation. In fact, this is really the only practical way to gain more cubes with the aluminum LS1 block, since bore increases are limited with the factory pressed-in cast-iron liners. A very minimal overbore-0.005 inch to 3.905 inches-along with an increase in stroke from 3.62 to 4.00 inches, yielded that magic Chevy stroker number: 383 ci.

As for component choice in the lower end, we plan to lean on this thing pretty hard, so we wanted to create a bulletproof short-block. The factory six-bolt main configuration is a more-than-solid foundation. Once it was filled it with a 4340 forged-steel Lunati crank and 4340 rods (6.125 inches long, a hair longer than the factory 6.098 pieces) along with JE Forged Side Relief (FSR) pistons that brought us in at a pump-gas-friendly 10.3:1 compression ratio, we knew we'd devised a bottom end that could handle anything we threw at it. And by "anything," we mean forced induction. But that's another story.

When it came to our heads and cam combo, we were primarily focused on making high-rpm horsepower, hopefully without totally sacrificing lower-end grunt. We went for the bottom-of-the-page choice and picked out a Comp Cams XER287HR. It's a big cam for an LS motor. According to Comp's Billy Godbold, the engine's basic architecture incorporates a very stiff valvetrain (thanks in part to the cam's 55mm core size). What does this all mean? The lobes are quicker, for one, getting the valves open further, faster. It also means that less duration is lost to valvetrain deflection, so they stay open longer. In short, the engine gets every bit of lift and duration promised on the cam card.

We teamed the big 'stick with AFR's 205cc LS1 Mongoose heads, which enabled us to kill two birds with one stone. On the one hand, these heads flow extremely well and are designed to accommodate LS1, LS2, or LS6 powerplants displacing as much as 408 ci, so they lend themselves to the high-rpm power we were seeking. On the other hand, the 205cc intake openings are designed to maintain high port velocity, which helps out with bottom-end power. "At low speeds, smaller ports do a better job of filling the cylinders," says AFR's Tony Mamo. "They really shine in the real world, making the engine more responsive at in everyday, part-throttle situations. These types of gains are rarely measured on a dyno, as most testing is done at WOT."

1. We topped our Victor Jr. LS1 manifold with a Holley 750 Street HP carb; best power numbers were obtained with a Wilson Manifolds 1-inch tapered combo spacer in place.

2. MSD's 6LS ignition controller is a real plug-and-play deal. You can use preprogrammed timing curve modules or program it with a laptop if desired.

3. MSD coil packs and Super Conductor wires provide higher-energy sparks for hi-po setups.

4. AFR 205cc LS1 Mongoose cylinder heads flow big numbers with high port velocity-the Holy Grail of head design.

5. This bargain-find Gen III block is filled with bulletproof internals from Lunati, JE, and Comp.

6. Need a little bling on your LS? The chrome balancer and bolt from Turn Key runs $225.

7. QTP makes this trick two-piece timing cover, allowing cam changes without disturbing the crank pulley.

Although most of Turn Key's Gen X engines are fuel injected-and we intend to try out EFI on this particular engine-we decided to go carbureted for this project. "We'll cater," said Turn Key's Kory Enger, so we bolted up an Edelbrock Victor Jr. LS1 manifold and teamed it with an MSD 6LS ignition controller. While we were looking to save a few bucks compared to the cost of an EFI system, the setup we used had one big advantage: simplicity. And sure, we're saying that installing the manifold, slapping on a carb, and dialing it in was simple. But the same thing goes for the MSD ignition controller-it truly is plug-and-play, especially if you go with one of the preprogrammed timing curve modules. How simple was it? This writer actually hooked most of the harness up, minus the power and ground wires. With that done, all that was left was to fire her up and have at it.

When all was said and done, it was hard to be disappointed with the results: 560 hp at 6,500 rpm, along with 505 lb-ft of torque at 5,100 rpm. And despite our emphasis on the upper end, we still managed a pretty broad torque band, maintaining 400-plus lb-ft from 3,300 rpm all the way to the end of the run at 7,000. They're good numbers, especially when you consider that we're dealing with only 383 ci and 10.3:1 compression. There's more in store for this thrown-away LS, but we're off to a good start. Check it out.

Quick Notes
What we did
Turned a cast-off LS1 into a potent stroker motor

Bottom line
We got big-block horsepower numbers from an aluminum small-block

Cost (approx)
$12,294

CAMSHAFT SPECS
Manufacturer Comp Cams
PN 54-448-11
Grind Number XER287HR
Type Hydraulic roller
Valve lift 0.605/0.609-inch
  intake/exhaust
Duration at 0.050 238/240
  intake/exhaust
Lobe separation 112
FLOW FIGURES
LIFT INTAKE EXHAUST
0.200 140 112
0.300 200 170
0.400 251 203
0.500 281 221
0.550 292 226
0.600 298 230
CFM at 28 inches H2O
PRICE LIST
MANUFACTURER PN DESCRIPTION PRICE
AFR 1510 205cc LS1 Mongoose heads  
    w/ spring upgrade $2,465
ARP 134-3609 Head bolt kit 150
Comp Cams 54-448-11 XER287HR 400
  7955-16 Hi-Tech pushrods 135
  850-16 High Energy lifters 189
Edelbrock 29087 Victor Jr. LS1 manifold 290
  or 2908 Victor Jr. LS1 manifold w/ module 690
JE Pistons 264041 F.S.R. Pistons 737
Lunati JO711ER Pro Series crankshaft 1,651
  6125FM3 4340 I-Beam Rod Set 1,460
MSD Ignition 82458 LS1/LS6 Blaster coil packs 632
  32079 8.5mm Super Conductor wire set 102
  6010 6LS Ignition Controller 313
Quick Time Performance QCC-LS1 Gen III Quick Cam Cover 425
Turn Key Engine Supply 872012 Chrome balancer w/ bolt 225
(including machine work) 7145 Double-roller timing chain 175
  12498544 Head gaskets (set) 50
  Balancing 200
  Cylinder boring 250
  Assembly on used motor 2,000
Yella Terra YT6645 Shaft-mount rocker arms 445
    Total $12,294
Options   New LS1 block 800-1,000
    New motor assembly 1,500
DYNO DATA
RPM LB-FT HP
2,600 369 182
2,700 372 191
2,800 370 197
2,900 368 203
3,000 369 211
3,100 374 221
3,200 385 235
3,300 404 254
3,400 416 269
3,500 424 283
3,600 427 293
3,700 433 305
3,800 441 319
3,900 448 332
4,000 456 347
4,100 459 358
4,200 461 369
4,300 465 381
4,400 474 397
4,500 480 411
4,600 487 426
4,700 491 440
4,800 498 455
4,900 501 468
5,000 503 479
5,100 505 490
5,200 505 499
5,300 502 507
5,400 499 513
5,500 497 521
5,600 497 530
5,700 496 539
5,800 494 545
5,900 487 547
6,000 483 552
6,100 476 553
6,200 469 554
6,300 464 556
6,400 457 556
6,500 453 560
6,600 443 557
6,700 438 558
6,800 428 554
6,900 418 549
7,000 407 542
DYNO DETAILS
Headers 1 3/4 Kooks long tubes w/ 18-inch extensions
Advance 32 degrees
Fuel 91-octane unleaded
Carb 750-cfm Street HP
Jets 73 primary/75 secondary
Max torque @ rpm 505 @ 5,100
Max power @ rpm 560 @ 6,500
Average torque 449
Average power 413
Build Sheet
Specifications not listed are the same as stock. Except as noted, all dimensions are in inches.
Displacement 383 ci
Bore x Stroke 3.905 x 4.000
Compression 10.3:1
Rod center to center 6.125
Piston deck height 0.00
Chamber volume 66 cc
Rod bearing clearance 0.0025
Crank endplay 0.003
Piston ring endgap 1.5mm top, 1.5mm second
Main bearing cap torque 58 ft-lbs
Main bearing/cross-bolt 20 ft-lbs
Rod bolt torque 85 ft-lbs
Head bolt torque 75 ft-lbs
Sources
Air Flow Research
877.892.8844
airflowresearch.com
ARP
800.826.3045
arp-bolts.com
Autotronic Controls Corp. (MSD Ignition)
915.857.5200
msdignition.com
Comp Cams
800.999.0853
compcams.com
Edelbrock Corp.
310.781.2222
edelbrock.com
Holley Performance Products
270.782.2900
holley.com
JE Pistons
714.898.9764
jepistons.com
Lunati
662.892.1500
lunatipower.com
Quick Time Performance
201.444.0998
quicktimeperformance.com
Rockett Brand Fuel
800.345.0076
rockettbrand.com
Turn Key Engine Supply
760.941.2741
turnkeyenginesupply.com
Westech Performance Group
951.685.4767
westechperformance.com
Wilson Manifolds
954.771.6216
wilsonmanifolds.com
Yella Terra
601.485.3355
yellaterra.com.au
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