When the C&V Performance VY Holden blasted down the quarter mile in
10.35-seconds it authoritatively established itself as Australia’s fastest LS1.
With a terminal speed of 135 mph, this baby doesn’t hang around – and Con from
C&V (the owner of the car) says it will go even faster in the same tune!
What’s even more remarkable is the limited number of mods that the car packs
under the lid.
Con explains that the guys at C&V have been doing a lot of LS1 R&D
over the past three years and last year they decided to showcase their efforts
with a company promo car. "We went for the SV8 LS1 because it’s lighter than the
SS. That was important because I weigh around 155kg and we wanted to keep the
weight down to a similar level as everyone else," he says.
The first mods involved drop-kicking the factory exhaust system and bolting
on C&V’s own design Tri-Y headers and twin 2 ½-inch exhaust system. Con says
a lot of hours were put into the development of the exhaust and he isn’t keen to
give away too many details.
The air intake was enhanced with by enlarging the feed into the airbox and
whacking in a K&N replacement panel filter.
To liberate the maximum power gain from the exhaust and intake, Con fitted a
UniChip interceptor to customise the fuel and ignition maps. Interestingly, the
factory ECU was also electronically recalibrated to provide a higher rev limit.
The engine will now spin to 6800 rpm. The ECU was also modified to alter the
shift points and the transmission line pressure.
At this time, the rear-end was changed to a shorter 3.9:1 ratio and the
torque converter was changed to a higher stall unit.
With these preliminary mods, Con took the car down the quarter mile and
recorded a low 13. Engine output at this time was around 310kW according to Con.
This figure has been converted from an at-the-wheels figure of 225kW (on a Dyno
Dynamics chassis dyno).
Next came the mod that would see the car plunge into low ET territory.
Con is an experienced hand when it comes to nitrous so he applied his
knowledge to the 5.7-litres of LS1. Con explains, "The system uses some
off-the-shelf parts from Nitrous Oxide Systems but the final system and the way
that it runs was devised by us."
In the first instance, a 100hp shot of nitrous (and enrichment fuel) was
injected by a single fogger nozzle immediately before the throttle. This ‘wet
manifold’ system provides a greater fuel/nitrous mixing than other approaches.
C&V also took this opportunity to replace the restrictive MAF pipe with a
custom aluminium big bore pipe.
Note that the nitrous is delivered only above 3000 rpm and the system is
armed by an aviation-style switch on the centre console. A second switch is used
to turn on the nitrous bottle warmer. (The temperature and pressure of the
nitrous are critical for system performance.)
At this stage, the fuel system was upgraded with a high-flow piggyback pump,
surge tank and adjustable regulator, which is used to force more fuel through
the standard injectors. The factory ignition system is up to the task. "It’s a
very good set-up for something factory," explains Con.
With the 100hp shot of nitrous aimed down its throat, Con knew road tyres
would’ve been next to hopeless so he went for a set of Mickey Thompson sticks.
The result?
Well, the ET tumbled to 11.8-seconds down from low 13s. Yep, that’s right –
these two changes alone dropped about a second and a half off the time!
At this stage, the engine was still completely stock internally – and Con
knew a lot more power could be released by playing around in the camshaft and
head department. The conservative factory cam was replaced by a C&V designed
cam profile along with a new gearset, valve springs and retainers. The
2-valve-per-cylinder alloy heads were then ported to give a potential 80hp gain.
At the same time, the throttle body was also exchanged for a SS Inductions job,
which offers more flow. Interestingly, the standard airflow meter is retained -
Con says they’ve tried a modified airflow meter but the improvement was
negligible.
Back on the long black strip the car – completely unchanged apart from heads,
cam and throttle – showed a 0.4-second improvement. An 11.4-second 117 mph pass
is not to be sneezed at.
However, it wasn’t completely smooth sailing. The standard axles weren’t
managing with the stress caused by slicks, so Con stepped up to a Diff Technics
9-inch diff with "indestructible" driveshafts. The transmission was also swapped
for the tried-and-proven GM Turbo 400 with various internal tweaks. Northmead
Auto Centre can be thanked for this work.
With the driveline now ready to take almost whatever could be dished up, Con
was confident enough to add another 100hp nitrous fogger to inject a 200hp
(total) shot of gas into the engine. Y-eah!
With shorter 4.11:1 diff gears and revised rear tyre diameter, the car has
recently freight-trained its way down the quarter in just 10.35-seconds (at 135
mph)! Con says it wasn’t even a particularly good run... So, without running to
its potential, the car has already broken the Australian LS1 record!
With a bit more fiddling with the chassis and tuning, Con is confident of
soon cracking the 10s. At present, Con estimates that the engine is putting
out around 700hp – but he’s unable to say for certain because they can’t stop
the beast from wheel-spinning on the dyno rollers. However, before any more
development is performed, a half cage is the first requirement under ANDRA
regulations.
As it is, Con says it has an awesome amount of go – especially when the
nitrous is flowing at mid-range revs. "It just goes like a train," tells Con.
"And that’s with all all-up weight of more than 4000lb."
On the street, the car is relatively stealth – sure, you can tell it has a
big cam an’ exhaust but that’s about all you’d suspect.
Con has limited visual mods to the essentials. This includes top lookin’
19-inch DTM rims wearing 245/35-series rubber. The ride height is also much more
attractive thanks to progressive rate lowered springs and re-valved Bilstein
dampers. Con has also fitted adjustable airbags to the rear suspension to aid
take-offs. Other nice touches include an aftermarket ‘Chev’ grille, rear badge
and some sticker work.
No, it might not be a show pony but when it’s the fastest LS1 in the
land, it doesn’t have to be!
Contact:
C&V Performance +61 2 9690 2000
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