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Super Performance
How much power can you extract from a 5.7-liter LS1 V8? That's the question Chevy Specialty Vehicles asked itself. And the Super Performance Camaro, based on an off-the-shelf Z28, is the answer. How does 530 horsepower at 6700 rpm grab you? That's generated by 485 ft.-lb. of asphalt-melting torque at 4900 rpm. Popular Mechanic's Editor-In-Chief, Joe Oldham, turned a 12.358 quarter mile at 121.11 mph, in this near-Pro Street machine on the strip at Memphis Motorsports Park. 'Nuff said.
But the beauty of this feat is that it was done with shrewd tuning of the stock engine, not bags full of money that bought a race-bred Keith Black Hemi. Jon Moss and crew began with displacement–adding it, that is. The OE cylinder liners were tossed in place of larger ones that yield a 4.00-in. bore. Squaring things up required a long-arm crankshaft that stretched the stroke up to another 4.00 in. So the factory 5.7-liter (350 cu.-in.) V8 became a one-off 6.6-liter (402 cu.-in.) monster. Forged aluminum pistons operate under a compression ratio of 13.0:1.
Of course, to fill those coffee-can cylinders now required better intake breathing. The aluminum heads were polished and ported and fitted with stock-size valves and retainers, plus custom-wound springs. A wild, custom-ground, roller-hydraulic, high-lift camshaft was inserted to operate the valvetrain at 44.5° of overlap. Further on up, there are 4.00-in. intake runners in the custom-made aluminum manifold, fed by dual 2.5-in. throttle body butterflies. Custom-bent 1-7/8-in.-dia. equal-length-tubing exhaust headers with 3.0-in. collectors spit out the spent gases.
Keeping all this port fuel-injected hardware in sync is a Delco-GM 1993 Corvette LT5 electronic control module. Ignition chores are handled via a hand-me-down module, coil pack and crankshaft/camshaft sensors from, of all places, a Cadillac Northstar V8.
A manual-shift Coan-built Turbo 350 Hydra-matic automatic transmission with 5000-rpm stall-speed torque converter sends all that torque down a steel propshaft. A custom-built Strange Engineering rear end then turns the oomph 90° toward the wheels. And the aluminum solid axle pushes the Camaro forward via four trailing links. A wishbone device attached beneath the differential keeps things tracking on the straight and narrow.
To keep this torque monster of a Camaro from twisting itself into a pretzel, the chassis had to be stiffened with a 4-post tubular roll cage fastened to full-length 2 in. x 3- in. rails welded into the floor pan. The trunk area was tubbed to accept the monster 31 x 10.5-in. drag slicks on 15 x 11-in. wheels. The front end is suspended by the stock upper/lower A-arms with Koni coil-over-shock units. Out back, Koni coil-over-shocks also keep the rump in the air.
The Super Performance LS1 Camaro weighs close to 3000 pounds, due to generous stripping of unnecessary parts. Yet the interior is completely trimmed with leather. It's a real Jekyll and Hyde act.
Chevy could never build a sellable version of this monster. It would cost too much. What's important, though, are the possibilities such a project brings to light.
Details
Body Style: 2-passenger, 2-door coupe
Engine: 402 cu.-in. (6.6-liter) LS1 aluminum ohv V8
Horsepower: 530 @ 6700 rpm
Torque: 485 ft.-lb. @ 4900 rpm
Bore: 4.00 in (101.6mm)
Stroke: 4.00 in (101.6mm)
Compression Ratio: 13.0:1
GM LS1 aluminum cylinder heads,
stud diameter upped by 1/2 in.
Manley 2.0-in. titanium intake valves
Manley 1.55-in. stainless steel exhaust valves
Isky Pacaloy valve springs
Lunati titanium valve spring retainers
Erson hydraulic roller camshaft, intake: 256°
(.050-in.) duration, .635-in. max lift, exhaust:
265° (.050-in.) duration, .050-in. max
lift, 44.5° valve overlap
GM OE LS1 hydraulic roller followers
GM OE LS1 investment-cast steel
roller fulcrum rocker arms, 1.7:1 ratio
GM LS1 cast-aluminum polished rocker covers, coil
mounts removed
Callies 5140 steel crankshaft
GM powder-metal cross-bolted main caps, 7/16-in. studs
Crower 4340 steel billet lightweight connecting rods,
6.0-in. center-to-center, 7/16-in. ARP bolts
Diamond forged aluminum pistons
JE piston pins
Wheel To Wheel double-row roller timing set
Wheel To Wheel aluminum short-runner
tuned-port, dual 2-1/2-in. throttle bores
K&N Corvette air filter system
1-7/8-in. tubular stainless steel 4-into-1 headers,
3-in. collectors
SX Performance No. 18201 frame-mounted
130 liters/hour fuel pump
SX Performance No. 15402 remote-mount
58.0-psi fuel pressure regulator
SX Performance No. 41002 high-flow filter
Bosch 5.2 gm/sec port fuel injectors
Aeroquip-8 feed and -6 return Pushlock hoses
and fittings
Transmission: Coan-built Turbo 350 3-speed Hydra-matic
Hurst Quarter Stick manual shifter
Gear ratios: FIRST 2.52, SECOND 1.52, THIRD 1.00:1
Drive: Strange Engineering rear axle and center section
for GM 12-bolt differential
5.13:1 spool-drive
Dyno-Tech 3.5-in. steel hollow
driveshaft, .083-in. wall
Dana-Spicer 1350-series U-joints
Wheelbase: 101 in.
Track, f/r: 64.5/55 in.
Weight: 2832 pounds
Suspension, front: A-arms, Koni adjustable coil-over-shocks
Suspension, rear: Solid axle, 4 adjustable trailing links, Koni
adjustable coil-over-shocks
Brakes: Strange Engineering 4-wheel-disc
drag brake system with line lock
Wheels: Monocoque aluminum, f: 15 x 4-in., r: 15 x 11-in.
Tires: Mickey Thompson E/T drag tires and slicks,
f: 27.5 x 4.5 in., r: 31 x 10.5 in.
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