Vehicle Description
This is one of those "we knew it when" stories. That's because we
knew SLP Performance Parts' Camaro Ultra-Z when it was "only" a
pewter, 550hp street car. Back then (all of two years ago), the car
sported a stroked LS1 and would lay rubber until either your right
foot got a cramp from pressing the pedal to the floor or the
seesawing hind end threatened to snap a 180-at 50 mph.
So, after a brief life as an on-the-edge street car, Reese decided
to take the car off the highway and get serious. Certainly, the car
has proved itself a worthy rolling tested for SLP Performance
Parts, but it also is an in house project that keeps morale pretty
high. Think of it this way: Where you had to fill out an expense
report for a taxi ride from the airport to the hotel, Reese turned
in an expense report for, say, an NHRA-legal rollcage. Is Ed
Hamburger a helluva boss or what?
"The funny thing is, it's a lease," says a grinning Reese, about
the now-Laser Red F-body (sprayed by Richfield, Ohio's Northcoast
Jet Clean). "We'll either have to return it to stock or buy the
car. You might see a 'For Sale' sign in the window someday, too.
But I don't even know where the back seat is right now." It doesn't
matter. The strip-bred Ultra-Z now packs a 650hp Gen III engine
(548 to the ET Streets), providing enough yank to pull the front
wheels and zip down the track to a best e.t. of 10.37 at 130
mph.
Displacing 427 ci (7.0 L), the motor powering the Ultra-Z started
out as the ultimate Gen III foundation- Corvette racing C5R
aluminum block. For the unfamiliar, the C5R block was developed for
the LeMans-winning GTS
Corvette team, and though it has the same outward appearance and
dimensions as an LS1 block, that's about where the similarities
end.
The dry, pressed-in cylinder liners on each bank of the block are
different than the regular production LS1, and the C5R block has
Siamese water jackets. This allowed adequate room to overbore the
cylinders to 4.125 inches (max 4.160). Combine that with a
4.00-inch stroke and you've got 427 big-block-style cubes.
Bottom-end beef includes a Callies Magnum Plus 4340 forged crank,
Callies Pro- (by Oliver) 4340E forged conrods, and Diamond/SP
forged pistons delivering 12.0:1 compression.
But while the stout bottom end delivers the displacement, making
power is all about moving air. The cam is a Comp Cams/SLP hydraulic
roller with 256/256 and 0.621/0.603 specs. The heads are
SLP-modified LS6 parts, with CNC-ported intake runners and exhaust
ports and 64cc chambers. The lightweight LS6 valves measure 2.00
inches on the intake side and 1.55 on the exhaust. The rockers are
SLP's own 1.85:1 parts. "They're the same heads we include with the
382 and 427 engine packages," says Reese. "The whole idea with this
car was to build something reflective of the capabilities we offer
'over the counter.' Anyone can order the same engine combination
from us." Well, almost anyone-at $25.500, the package isn't exactly
cheap.
SLP's heads flow like the wind across Nebraska, with the air stream
generated in a ported LS6 intake manifold capped by a prototype
85mm throttle-body. Thirty-eight-pound injectors, fed by an SX pump
and regulator, ensure a more-than-adequate fuel supply. The fuel
tank was replaced by a trick fuel cell setup, and the stock fuel
lines were scrapped in favor of half-inch teed and return lines.
The Camaro's stock quasi-returnless fuel system, says Reese, is
totally inadequate for the engine's needs.
As for exhaust, SLP's 131/44-inch, tuned-length, stainless steel
long tubes feed a pair of custom collector mufflers with dumps. The
remainder of the car's drivetrain is fairly straightforward strip
stuff: a Yank-built Turbo 400 with a 3,200-stall 9-inch converter.
The obligatory transbrake and Hurst Quarter-Stick are in place, as
is one of SLP's Moser-built 12-bolt rearends. Again, it's one of
those "out of the catalog" parts SLP installed. For the Ultra-Z,
the rearend boasts stronger axles, 4.11:1 gears, and a spool. The
whole assembly turns a set of 15-inch Weld Wheels with Mickey
Thompson ET Drags (28.0x11.5) or ET Streets (26.0x11.5).Keeping
that rubber planted at the Tree is a bunch of SLP suspension parts,
including the company's adjustable torque arm. HAL shocks are used
at all corners, while the modified, but stock, rear springs house
airbags. To stiffen the F-car's notoriously flexible chassis, SLP's
subframe connectors and shock tower brace were also added, and SLP
scratch-built the car's rollcage.
In a nutshell, the Ultra-Z is prepped for one thing: launch. "It's
pretty sick." says Reese. "It comes off the transbrake around 3,200
and just blasts off-the tires stick like glue. It tracks super
straight thanks to a heavy preload of the passenger-side
suspension, as well as proper shock valve tuning and airbag
biasing."
Thing is, 10.30s are just a first blush. "The Ultra-Z was in pieces
two days before we had to leave for one of SLP's
customer-appreciation events, and we promised the car would run
down the track," says Reese. "When the car got back from the paint
shop, it was a thrash to assemble it. Hank Daniecki, Tony Kalapach,
and Ken Estelle deserve most of the credit for putting the car
together-and making it run." As a rolling laboratory, the form and
function will continue to evolve. "We'll be in the 9s shortly,"
says Reese. "We just need to put the car on a diet. I'd like to get
it down to about 3,250 pounds, but without completely tearing out
the interior. We're going after hidden
weight."