Tackling High Performance Work
By Dave Emanuel
Obviously, there are many questions to be answered
before a shop enters or expands its activities into the high performance
arena. There are moderately successful performance-oriented machine
shops scattered from one end of the nation to the other. There
are also a significantly smaller number of VERY successful shops.
Typically, the difference between the former
and latter is notoriety; owners of the most successful shops have
done something to distinguish themselves from the rest of the
pack. In some instances, it's building engines for at least one
racer who consistently winds up first at the finish line; for
others, it's attention in national magazines and reputation built
over the years.
Specialization is also an important factor
in many shops' formula for success. Race engines of any particular
type have become so highly developed that it's virtually impossible
to build a competitive engine unless you have the opportunity
to do research and development. It may be possible to "buy"
some R&D by inspecting a competitive engine built by another
company, but this is a stop-gap band-aid at best.
Engine technology is continually evolving,
so constant dyno sessions are a necessity if a company is to be
able to build competitive engines for many types of racing. Given
the equipment and personnel commitment required to successfully
engage in high performance work, it may seem as though it creates
more problems than profits. And it can.
Bill Hancock of Arrow Racing Engines, Rochester
Hills, MI, has worked "both sides of the street." He
has a background in production engine rebuilding, but since 1979,
his company has been involved almost exclusively in race engine
building and research and development. Hancock notes that there
are many opportunities for traditional shops to expand into high
performance work, but he says you have to be cautious.
"You have to be careful and selective
about the type of work you take in," said Hancock. "My
advice is to stay away from anything that makes more than one
horsepower per cubic inch, at least until you get some experience
under your belt. It isn't necessarily that a traditional shop
can't do the work, but there are a number of considerations that
you may not be aware of.
"As an example, suppose a customer comes
in with a crankshaft balanced and the connecting rods rebuilt.
If it's a production engine and you screw up the crank or rods,
you can go to any number of places and get a replacement for a
few hundred dollars. The customer may be inconvenienced for a
day or two, or he may not even be aware that there was a problem.
"But when a racer comes in with a billet
crank and a set of Carillo rods, you're looking at a considerably
higher replacement cost. And that's the least of it. The real
problem is that at most times of the year, there's an 8-10 week
lead time to get replacements. If he's a professional racer, you're
dealing with his livelihood; if you damage his parts, you've put
him out of business for two months. No matter how you handle the
situation, he's not going to be happy."
Another consideration is the difference between
tolerances in production and race-oriented components. Hancock
notes, "True race heads don't lend themselves to production
tolerances and methods. You can do a valve job and lose 20 hp
- even though the valve job is technically perfect -
just because seat machining reduced air flow.
"You can't argue about it either because
the differences will show up on the flow bench and on the dyno.
Decking a set of heads can also cause similar problems. You have
to be familiar with the specific head casting you're working with
and you also have to be aware of racing class requirements. Things
are less critical if you're working with a bracket racer or a
Hobby Stock type oval track racer, but you still have to know
the territory. If you do, there's plenty of opportunity for profitable
Mike Osucha of Mike Osucha Racing Engines,
Charlotte, NC, has found some of those opportunities. Osucha states,
"We do some race work, but our specialty is custom high performance
LT1 and LT4 engines for late model Camaros, Firebirds, Corvettes
and Impalas. Most of the engines that we build are installed in
street-driven cars that are rarely taken to the drag strip, so
we have pretty much relied on dyno results to tell all of the
"When you get over 500 horsepower from
a true late model street engine, people pay attention. Fortunately,
a number of our engine projects have been covered in national
magazines, and that has really helped our business."
Osucha, who is a licensed aircraft mechanic
and a precision machinist, notes that most high performance customers
spend a lot of time talking about horsepower, but they also have
strong concerns about reliability. His advice is to be honest
and up front with customers.
"A lot of high performance engine buyers
couldn't change spark plugs if their life depended on it,"
said Osucha. "But they've read enough and listened enough
to speak intelligently about specifications and components. If
you want this person's business, you have to be up-front and honest.
"We've had a number of customers who had
work done by other shops and the engine just didn't last because
they had used inferior components. But they charged the customer
for the good stuff, thinking he'd never know the difference. That's
a good way to earn the type of reputation that will put you out
of business. I've found that it's best to discuss specifications
and components with the customer and be realistic with power estimates."
Osucha also pointed out the need for qualified
shop personnel, a sentiment echoed by Garry Grimes of Grimes Automotive
Machine, Alpharetta, GA. Grimes has been machining and building
race engines for more than 25 years and he states, "With
high performance work, you're usually working in specialized areas
and customers frequently know as much about specific tolerances
and materials as the person doing the work. So you have to be
"If you're machining parts for a high
performance customer, you can bet he's going to check everything
you do. Even if you do a complete engine and deliver it ready
to race, somewhere along the line someone else is going to take
it apart and check it. If you've done inferior work, word will
get around quickly.
"Even when you do everything right, you're
going to get complaints, that's part of it. But high performance
work has been very profitable for us and it's helped increase
our standard machining and rebuilding business too. However, if
you don't really have an interest in high performance engines,
and are going into it just to increase business, I think you're
wasting your time. You've got to be involved to be successful."
Assuming that horsepower in large amounts does
have some allure, the best place to begin in high performance
work is at the top - with cylinder heads. For openers,
it offers a better parts/labor ratio. Every dollar spent on head
work generates about two dollars in parts sales. On the other
hand, with block work, the ratio is about one-to-one.
Another advantage is that you can teach head
repair work in a minimal amount of time - usually six weeks
or less. It's pretty repetitive work so a person can get up to
speed pretty quickly and stay there. On the other hand, blocks
constitute a completely different type of challenge.
When a race engine comes in for a rebuild,
it should be disassembled by a person who is naturally inclined
to study the incoming parts to determine what caused the wear-out
or failure. That person must also be capable of operating a variety
of different machines. With cylinder head work, you primarily
need someone who can operate valve and seat cutting equipment,
some type of surfacer, cylinder head pressure testing system,
If you're planning to buy valve and seat grinding
machinery, take a long, hard look at the new generation of valve/guide/seat
equipment that uses seat cutters rather than stones. The cutters
machine three valve seat angles in a single pass. Both the angles
and widths are predetermined by the cutter shape, so repeatability
is virtually 100%.
That's important because in addition to completing
the valve job more quickly, and with greater accuracy, holding
a constant seat depth keeps combustion chamber volume from varying
excessively. These cutters can be up to three times faster than
conventional methods in applications using oversized valves. But
you'll still need some conventional seat grinding equipment for
freshening up mildly worn seats if nothing else.
The consensus among many high performance engine
builders is that anyone venturing into high performance machine
work should begin with cylinder heads. The equipment needed costs
a lot less than block machining equipment, and it will probably
be used in 60-70% of the business you do. As volume grows, the
need for a valve/guide/seat machine will become more critical;
most shops use their valve/guide/seat machines for a wide variety
of operations including valve seats, guides, screw-in studs, oversized
spring seats, valve guide OD machining, heli-coiling, milling
pedestals down, and even some bowl work.
Other cylinder head-oriented equipment that
should be on hand are a surfacer (belt sanders are inappropriate
because they don't offer consistent stock removal and can destroy
carefully machined deck angles) and a burette so you can check
combustion chamber volume
The typical high performance customer (as opposed
to racer) wants a three-angle valve job, premium quality valve
guides, the spring seats and valve guides cut for dual valve springs
and special seals, port matching, some bowl work and the chambers
cc'd. That's the type of work a shop that's new to high performance
work should be set up to do.
Another prerequisite is a good cleaning system.
Before you can machine a head or block, it has to be free of all
the dirt and grease it has accumulated in its previous life. If
environmental considerations make installation of a system prohibitively
expensive, make arrangements with another shop to do your cleaning.
If you're ready to jump into high performance
block machine work, the first prerequisite is a quick and accurate
boring and honing system. That means a first class boring bar
and a semi-automatic honing machine as a minimum. Even if you
have the skill to hone a block satisfactorily with a hand held
drill, you won't have the time.
To ensure optimum cylinder wall finish, it's
usually necessary to hone .004ý to .005ý after boring.
That honing is ALWAYS done with torque plates attached. As Grimes
puts it, "Tooling for your machines is everything. If you've
got equipment and no tooling, you've got a yo-yo without a string
and with honing, the torque plate is your tooling.
"Cylinder walls will move more than .003ý
when the head bolts are tightened and if you don't simulate the
bolt loads while you're honing, you can't do a proper job. Remember,
cast pistons are very forgiving, but if the customer is going
to install forged pistons and keep piston-to-wall clearance relatively
tight, chances are the pistons will gall if torque plates aren't
used during honing.
"The situation has gotten worse since
the late '70s when most of the factories went to thin wall block
castings. Cylinder wall movement varies according to engine type,
and some blocks are noticeably worse than others. But even the
best ones are bad enough that use of torque plates while honing
is definitely a necessity."
Of course, it's always advisable to know how
thick the walls are before you start machining. Sonic thickness
testers aren't cheap - about $2,000 - but they can be worth
their weight in gold. Whether you're machining a customer's block,
or one that you supplied, a failure due to insufficient cylinder
wall thickness is not good for customer relations - regardless
of who supplied the block or specified bore diameter.
Another advantage of a sonic checker is that
customers may bring their blocks to you for checking and that's
a good way to start a relationship that can lead to increased
business. Most shops charge $50-$75 to sonic check a V8, so it
doesn't take too long for the tester to pay for itself
Another piece of equipment that's standard
fare in high performance machine shops is an align hone. Align
boring is typically needed only when installing special or replacement
main caps, however, align honing is needed on almost every block
- even brand new ones. Factory machining is rarely up to high
Connecting rod reconditioning and balancing
equipment rounds out the basic requirements for a high performance
machine shop. It all adds up to some pretty healthy expense, so
it may not be possible or economically feasible to purchase all
the necessary equipment at one time.
Another 20-year veteran of the high performance
business, Myron Cottrell of Cottrell Racing Engines, Chaska, MN,
advises, "Find out what work you can get done by other shops,
then concentrate on the equipment you absolutely have to have.
You definitely need the equipment, but to me the first priority
is a good machinist. Find one and pay him well because by getting
the work done right the first time, a good machinist drags in
a lot of parts business."
Another important point that a lot of people
don't think about is the relationship between a machinist and
the person working the counter. A lot of high performance sales
are time consuming because sometimes you have to explain to a
customer that his needs are beyond what he thinks they are. All
the time that a machinist spends talking to customers is time
away from being productive.
A certain amount of that goes with the territory,
but you can turn out a lot more machine work when the counter
person can handle most of the conversation with customers. Just
make sure everybody communicates well so signals don't get crossed.
Without question, there is money to be made
in high performance machine work, but it's not all sunshine and
roses. And the nature of the business has changed in recent years.
Traditionally, the overwhelming majority of customers for high
performance machine work were owners of domestic V8 engines. The
only interest in four and six-cylinder engines was centered on
a comparatively small number of road racers and a rare drag racer
or street performance enthusiast.
In the mid to late '80s, V6 engines attained
increased popularity as the future of production V8 engines became
dubious. Many oval track racing series attempted to encourage
a switch to V6s and in some divisions, rules made V6s the only
game in town.
Growing import performance market opportunities?
By the time the '90s got into full swing, V8s
had reasserted their dominance and interest in high performance
V6 engines slackened, although V6s are still the engine of choice
at a number of racing venues. More recently, demand for high performance
six cylinder and four cylinder engine work has increased, fueled
by interest in imported vehicles. That interest stems largely
from road racing where imported cars have predominated for some
Recently, import drag racing has been adding
fuel to the fire. At this point, most performance-oriented import
owners are geared towards bolt-on equipment - headers, intake
and exhaust systems, camshafts and superchargers - but cylinder
head modifications are becoming more common. According to Grimes,
import owners are starting to dive into their short blocks in
increasingly larger numbers.
"What we're starting to see is that the
customer with a Nissan, Toyota or Honda is just like the guy with
a small block Chevy," explained Grimes. "He wants more
horsepower for his street car, so it's faster than his friends'
cars and when he decides to have an engine built, he wants it
to have good components inside. We haven't seen much drag racing
influence yet; at this point, all the street performance action
with imports has come from road racing."
Naturally, every machinist has a different
opinion about which types and brands of machines are best, and
which segment of the market is most lucrative. But one thing they
all agree upon is that to be successful with high performance
machine work, you have to know the market and you have to do things
right the first time.