HARTLEY
HARTLEY
SUPER STOCK
ENGINES
Hartley would like to put the V12 into something
exotic. “But just for one or two partners, not for
just anyone who walks through the door," says
Nelson. "At the moment the future of the engine
design is a little uncertain, so we don't want to
contaminate the future market by selling it to
anyone who asks for it – it’s too unique to do that
and if we do, it will never be an exclusive engine
for an exotic sports car maker.
“It’s a nice engine, I wish I could take all the credit
for it, but I haven't reinvented the wheel with this
motor, we’ve just done what we normally do – I’ve
just done more of it on this job," says Nelson.
"What I’ve realised doing this job, is that what we
can do normally and what we take for granted,
lots of our competitors can't do, which gives us a
useful edge. There are very few engine companies
around the world doing what we do. There’s not
really many companies that can take on a small
bespoke engine production job. A lot of our
competition build engines from essentially kitsets
of parts, whereas we make or modify everything in
house.
“Building a high-performance engine is fairly
straight forward, but doing it reliably, efficiently,
cost effectively and with repeatability is not easy,
but that’s what we’re quite good at," says Nelson.
"I’d like to do more jobs like this, and I am really
interested to see what the future holds.”
The last word from Nelson – “It’s freakin’ cool.”
Super Stocks is about the biggest race
category in New Zealand. “It’s like Nascar,
but nothing like Nascar – it’s full contact
motorsport," says Nelson. "It’s similar
to the BriSCA Formula 1 Stock Cars in
the UK, but also still quite different”. The
cars weigh about 1,500kgs, have 500 –
550bhp and they run on ¼ mile oval dirt
tracks. The engines have to be built to
stay in one gear all the time. They use
tiny, hard tyres. The engine regulations
are 4L maximum capacity, with a
maximum of 10:1 compression ratio and
naturally aspirated with a big carburettor
running up to 10,500rpm.
“It’s seriously impressive and makes V8
Super Car engines look like toys (except
for the rule forcing us to use carburettors…
what year is it?)," says Nelson.
"We are building them for purpose built
demolition derby cars. They use custom
billet manifolds that start out with 50kgs
of aluminium and we machine them down
to 4kgs, we’re making crankshafts and
conrods and we are making valves and
camshafts and I just can't make enough
of them. They are based on a Nissan
VK56, and a Toyota 1UZ-FE VVT- i we go
bigger in the bore and shorten the stroke
so we can meet the 4L limit and pull lots
of revs.”
At a recent championship about 80 – 90
professionally built cars showed up and
there are a handful of drivers that do it
for a living. “This kind of enthusiasm for
the category makes the V8 Super Tourers
look like a waste of time," says Nelson.
"The Super Stock guys can fund their
entire racing from sponsorship. Typical
crowds are 15 – 20,000 people too.
“Our lowest budget engine is based
around the Toyota 1UZ – the other rule is
that it has to be OEM block and heads
if you’re using a multi-valve engine,"
says Nelson. "This is great as it stops
us making our own casting and keeps
the costs down a bit. The lower budget
engine is around $35,000 depending on
specification. They are all dry sumped
with titanium valve spring retainers,
proper high-end valves and springs, CNC
ported heads and billet manifolds. The
manifolds have a single arc from the valve
head to the carburettor butterfly and this
is virtually unheard of in this category.
“We build lots of Toyotas and quite a few
Nissans – the Nissan runners have higher
budgets, so we don’t build as many,"
says Nelson. "We also do Toyota kitsets
for other engine builders and people on
lower budgets who want to build engines
themselves. The kitsets are actually
quite useful, because we just don't have
the time to build everyone a motor. Our
development rate seems to be much
higher than most other people, because
we do so much of it and have the tools
we can develop stuff faster and better
than most people and we can spread the
costs by selling kitsets to other engine
builders. It’s one of those situations
where everyone wins and our developments
have been good for the category
as well, and it’s really flourished because
of it. It would be good to see more of this
happening in other categories of circuit
racing, whereas it’s all spec or one make
formulas, and everyone seems to be
taken for a ride in terms of chassis and
engine costs. In contrast in the Super
Stocks there are probably 30 different
chassis manufacturers, maybe 10 or
so big ones and similarly with engine
builders."
The racing looks a bit like semi organised
carnage, but it’s actually quite technical
to get these cars to work at all. “They
are seriously heavy and their tyres are
small, narrow and hard and the racing is
really close, because they can basically
run bumper to bumper it creates a
completely different dynamic in the
racing," says Nelson. "Because it’s a full
contact category, if you try to block you
will just be put in the wall. Controlling
from the front is difficult, the best place to
be going into the final turn on the final lap
is second.”
You can buy a fairly competitive used
car for about $30-40,000, but such is
the nature of the sport – you never stop
spending. Apart from the contact nature
of the category, the thing that makes it
unique is the start. All the competitors
are touching bumper to bumper, side by
side at the start and they go into turn one
like a solid slab of metal. That’s when the
mayhem begins.
“They actually go quite quickly, given the
weight and the tyres," says Nelson. "It’s
quite tactical too as the fastest line often
leaves you quite exposed. If you want to
get passed someone you can legitimately
turn them around.”
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