feature - Engine Professional

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FEATURE
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HEAVY
DUTY
ENGINES
Why diesels are good business
BY JOHN STEWART
Photos BY JOHN STEWART and courtesY of the manufacturers
Anywhere loads are to be moved or work
is to be done, heavy duty engines are
there. Generally, these are diesel engines,
which are efficient in situations where
loads are heavy and steady engine speeds
are the norm. These include agricultural
pumps, marine propulsion, buses and
shuttles, over the road trucks and motor
homes. Some of the most common are
those made by Cummins, Isuzu and
International for use in Dodge, GM and
Ford heavy duty pickups and mediumduty trucks. In motor homes, Caterpillar
and Cummins engines are often seen, and
for agricultural use, John Deere and
Caterpillar are common brands.
Lately, there has been a surge in diesel
pickup truck pulling and racing, resulting
in demand for high-performance versions
of some of these engines.
We talked to a number of engine
builders, machine shops and performance
parts manufacturers to get an idea about
the heavy duty end of the engine business.
In some regions, doing rebuilds for dealers is the volume part of the business, in
other areas it’s agricultural and industrial
diesels. At Manitowoc Motor Machining,
in Manitowoc Wisconsin, the farm equipment is most common.
“Most of what we see is agricultural,”
said Scott Wichlacz at Manitowoc. “The
Case IH stuff, Cummins and John Deere
are what we see the most often.” A lot of
these engines are worked hard for long
hours, and could be “just worn out.”
“But usually it’s lubrication failures. It’s
not necessarily the quality of the lubricants, or that they’re not changing them
enough, most of the time it’s contamination by fuel or by coolant.”
“Fuel dilution means something with
the injection system is going bad; if it’s
coolant contamination, it’s generally due
to wet sleeves leaking. Most of these
engines have wet liners in them, so the
seals on the liners will leak, and that precipitates the failure because your oil is
contaminated by coolant.”
Manitowoc is primarily a machine
shop, with the capabilities to handle larger, longer parts found in big diesels. They
can make specialty parts as well, such as a
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FEATURE
cylinder Deere engines, and do dyno testing, engine balancing, crankshaft straightening and cylinder head machining.
Of the lighter-duty diesels, Cummins
B6 engines are fairly common. “We see a
fair amount. We’ve seen some with cylinder head cracks. The Cummins B-series
engines that are used in agricultural
equipment, that’s usually a different story.
There it’s usually air filter problems,
where they haven’t changed the air filter
or weren’t able to get it in correctly. Dirt
gets in the engine and wears it out.”
On an engine built to last, such as
most diesels, the importance of oil and air
filter maintenance can’t be overstressed.
Those engines in dusty or sandy environments are in particular jeopardy.
“The biggest cause of failure on the
heavy duty diesels, says Dwayne Dugas of
Dugas Engine Service, “is not changing
the air filter, or poor air filtration systems.
A lot of the jobs that we do offshore have
sand blasting going on, so they ingest
sand which is really good for our business.”
Even though HD engines are designed
for the long haul, that doesn’t mean there
aren’t weak points.
“A lot of them have their own characteristics,” says Kenny Burns at Harry’s
Machine Works. “It seems every motor
has its own weakness or two.”
How HD is different
Burns tells us that about 65 to 70 percent
of the business at Harry’s Machine Works
is heavy duty and ag-related. From his
point of view, working on heavy duty
engines can be good business just because
you have a better customer.
“There’s a lot less problems, from
what I see… most of the people working
on the larger equipment are more knowledgeable about what they’re working on.
The dealers are a lot more knowledgeable
than people trying to repair their own
vehicles; you don’t have to explain as
much in detail to the dealers as you do
the backyard mechanics, who are trying
to save a dollar. Also with the warranty
issues, you have to explain so much to
somebody who is not familiar with them,
to keep them from having a problem. So
it’s a lot easier.”
Wichlacz at Manitowoc points out
that HD engines are largely the same as
any other engines, with some exceptions.
“What people are not used to is doing
valve work. Doing valve protrusions and
recessions, that’s not what somebody who
only does common passenger car stuff
would ordinarily be familiar with. But
12 APR-JUN 2009 engine professional
AERA does have those specifications in
the PRO-SIS program, so that helps someone who has not been in the heavy duty
business. If they look at their technical
bulletins and service bulletins, they will
help them through most of that.
“The other difference,” Wichlacz
observed, “is sheer size. Pretty much anybody who has automotive equipment can
do most of the common and compact-size
diesels. When you get into the larger
diesels, then the equipment becomes an
issue. You need to have larger machining
equipment to deal with larger cylinder
heads, larger blocks, larger crankshafts
and so on.”
Burns agrees that the HD engines are
bigger, and heavier, and require “a lot of
hoists, and bigger machines, of course.”
Dwayne Dugas at Dugas Engine
Service puts it this way, “It’s really not
that different, other than the weight, and
you can get a better dollar for your work
compared to regular automotive.”
New Emissions Rules
One of the biggest changes in the diesel
world is that new, very strict emissions
regulations have arrived. That’s changed
the engines, the fuel and lubricants, and
changed the business itself.
Burns observed that now, “A lot of
people are trying to restore their old
engines. They haven’t quite got the
engines figured out for the new rules;
there are problems they haven’t addressed
yet. So there are a lot of customers who
will spend the same amount on an old
motor as they will on a brand new one-just to stay away from it.”
It’s not just engines on pickup trucks,
either. “Emissions (rules) are coming
through on the irrigation side of the business too, and that’s raising the price of
new engines. That’s actually helping our
business out,” Burns said. “If they put a
brand new engine out on a well, most of
them are natural gas for the fuel savings.
It’s adding anywhere from two to four
thousand dollars on a brand new motor.
So that’s getting our rebuilds back into
the price range where before the new
motor used to be fairly cheap to go out
and buy.”
All the new engines now require CJ-4
low ash lubricants and run on ultra-lowsulfur diesel fuel. Many, such as Deere
and Cummins, are certified to run B5
biodiesel, or even B20, without voiding
the warranty.
Known Issues and Fixes
6.0L Ford/Navistar Power Stroke engines
have been notable for warranty issues.
These included EGR valve sticking due to
carbon deposits, which can be remedied
by installing a new stainless EGR cooler.
“The EGR cooler, a lot of times, leaks,
puts water in the cylinders, creates a
hydraulic effect, which blows the head
gasket,” Dugas noted.
It also became clear early on that the
engine was not designed with sufficient
performance headroom to permit aftermarket re-programming, which created
further problems. In addition to defective
sensors and other quality control issues,
head gasket failure became a common
cause of repair, for several reasons.
Owners were tempted to extend the rev
range of the Navistar 6.0L beyond the
3600 fuel cutoff by means of aftermarket
programming. This created more pressure
in the combustion chamber.
“Especially on the 6-liter, there was a
design flaw--not enough head bolts. The
head bolts pass through an aluminum carrier and cast iron head, and you just don’t
get the clamping force,” Dugas noted.
This can be addressed by replacing the
torque-to-limit head bolts with head studs
that offer better clamping power. Later
editions of the 6.0 and its replacement,
the 6.4L Power Stroke, have a better
repair record.
“International actually sent us a 6.4,
because they appreciate their problem
with the six liter, and they sent us one to
do form/function study on it. So we’ve
got parts for that.” says Chris Raskey at
ARP, a company that manufactures hardware for racing applications. “There are a
couple of reasons you would want to
change a fastener. One is you want a
clamping load to keep the gasket in, the
other is you want to use it over instead of
buying a new set every time,” Raskey told
us. Racers and owners of modified Power
Stroke engines generally upgrade to studs
as a precautionary measure, but not every
engine rebuilder is convinced that will be
a lasting solution. “I can’t say there is a
good fix for that… there is still an issue
there, because we’ve done some and
upgraded the bolts, and they still had
some problems,” Dugas says. Dugas does
work for Ford dealerships and mentioned
that Ford considers the heads nonrebuildable after a certain degree of
warpage, and that the specification has
recently been amended. “They want you
to measure warpage from side to side,
rather than from end to end,” he said.
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RIGHT: There are millions of “heavy duty” diesel engines to be found
in light- and medium-duty trucks, such as the Cummins 5.9 B6, the
GM/Isuzu Duramax 6.6 and the Ford/Navistar Power Stroke. Working
on them is just like working on any other engine, but they are bigger,
heavier, and require some specialized equipment.
BELOW: Diesel racing has increased in popularity, and as a result,
demand for performance tuning and performance rebuilds has been
on the upswing. This particular Freightliner rig has a Cummins Six
that has been tuned by adding a performance box to control fuel,
another electronic box to control timing, and water/methanol injection
to cool combustion. During the work week, the tuning is readjusted
for better mileage, and at the track, for power.
LEFT: Over 1.5 million of the 5.9 Cummins B6
engines have been made since the engine was
first developed by Cummins and Case
Corporation for agricultural use. The Cummins
B motors have a very heavily built bottom end
and have proved to be popular for use in diesel
motorsports. The engine, now widely used in
Dodge pickups, has morphed into a 6.7L that
has cooled EGR, variable geometry turbo and
high-pressure direct injection to meet 2010
emissions requirements. Unlike current 6.6
Duramax and 6.4L Power Stroke, the Cummins
B6 does not use aluminum heads.
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FEATURE
Duramax
On the GM/Isuzu Duramax engines, the
newer 6.6L V-8s are considered reliable
and good material for Hot-Roding, especially the 2006-2007 LBZ. However, there
have been reports of some premature
crank wear due to failure of the harmonic
balancer. These are frequent enough that
an aftermarket part made by Fluidampr is
frequently substituted, especially in performance applications. The LB7 engines
had injector failure as a common problem, which could lead to oil contamination and larger failures resulting. The subsequent LLY was modified to improve
access to the injectors.
“We haven’t seen a whole lot of problems with the 6.6,” Dugas said. “When
they first came out they had some injection issues, and that seems to be resolved.
Normal stuff, like on an ambulance, they
wear valve guides because of so much idle
time, but overall I haven’t seen a trend of
any problems with those at all.”
The prior GM diesel engines have a
mixed record. Both the 6.2 and 6.5L
Detroit Diesel/GM engines were subject to
main bearing web cracks. That problem
was eventually addressed with a combination of improved higher nickel, cast iron
alloy as well as a lower block redesign
that includes a main bearing girdle.
Cummins B-series
The Cummins B6 is considered to be a
reliable engine, delivering good economy
and value, but there have been reports of
unreliable fuel delivery systems in certain
Cummins B engines. “In the B series, we
do see a lot of piston and ring failures on
the 75,000 to 100,000 mile range,”
Dugas mentioned. “I suspect the fuel system but I don’t have anything to back
that up and prove it.” For whatever reason, there have been a number of fuel systems on the B-motors over the years. The
injection pumps were VE from 19891993, the P7100 from 1994-1998.5,
before going to the Cummins Electronic
VP44 ISB 5.9 in 1998.
In the 24-valve 5.9 with the Bosch
VP44 injection pump, if the fuel pressure
drops the electronics in the injection
pump can overheat, causing the pump to
fail. Generally the lift-pump needs to produce pressure of 12 to 16 psi at idle;
below 8 psi and the injection pump risks
starvation. There are a number of low
fuel pressure warning kits available to
provide early warning for this problem
It’s also known that a series of 5.9L
engine blocks cast in Brazil have a tenden14 APR-JUN 2009 engine professional
cy to crack. These blocks can be identified
by the number 53 cast on the driver’s
side. There are metal stitching techniques
that can address this problem to save an
otherwise sound block.
Perhaps most notorious is the “killer
dowel pin” (KDP) problem that appears
5.9L B engines from 1989 to 1998.5. In
these engines, a steel dowel pin is pressed
into the block to locate the timing gear
housing. These pins have the tendency to
vibrate free over time and drop into the
aluminum cam gear housing on the front
of the engine, breaking a chunk free and
causing loss of oil. In late 1998 the timing
cover was changed to a tapered design
that did not allow the pin to fall out. For
earlier engines, KDP repair kits exist that
include a tab to prevent the pin from
coming loose. Generally the repair
involves about 4 hours of labor to get to
the pin and secure it.
Performance Potential
When it comes to modifying diesels for
performance manufacturers issue stern
warnings, and engine rebuilders generally
agree. For starters, the newest diesels are
already highly engineered, with integrated
electronic systems. Gone are the days
when operators could just turn up the fuel
flow with a screwdriver.
“The newer diesels are just like the
race cars,” Burns pointed out. “They’re
moving their top ring land up, to get all
the compression they can on them, so
there’s no wasted space. It’s a lot more
high performance than it was 20 years
ago; everything’s moving up. It doesn’t
matter if it’s over the road or agricultural,
they’re trying to get more torque and as
much horsepower as they can as far a
cubic-inch goes, and they’re doing it. But
there are failure rates because of it. Piston
failure is what we see the most of.”
Dodge’s warning language for owners
of their newest B-motor, the 6.7, is typical
of the OEM position: “Keep in mind that
your 6.7 liter engine is a sophisticated,
fully integrated system. Some aftermarket
products can jeopardize this system and
cause severe power system, exhaust system and engine damage. These so-called
aftermarket ‘performance chips’ may
carry claims to increase horsepower and
torque output. These non-original chips
can alter how your engine operates and
their claims are neither authorized nor
recommended by Dodge or Cummins.”
Burns: “What I explain to a customer
is, if the factory could afford to warranty
it at the horsepower that they’re trying to
achieve, then that’s where they would
have put it. We do have a lot of people
who either turn up the diesel fuel, or
propane-inject the diesel. They go with
bigger turbochargers, different chips. And
that’s all up to the customer, but I tell
them if it was a safe operating level with
that, the factory would have put it there.”
Generally speaking, by adding more fuel
the mix becomes overly rich, and greater
heat is generated on the exhaust side.
Exhaust gas temperatures (EGT) rises and
the risk of thermal failure of exhaust
valves and pistons become evident. In
some cases, unauthorized modification of
factory engines has created warranty
nightmares for the manufacturers.
Diesel Racing
Nevertheless, one of the newest motorsports trends is diesel motorsports. In
these events, owners of heavy duty Ford,
Dodge and GM pickups gather to try
their hand at drag racing, pulling and
dyno-testing. In many cases, they have
installed equipment that can be tuned for
power with the twist of a knob, and detuned for everyday use at the end of the
day. With all the interest in drag racing,
full-size pickup trucks are now running
surprisingly fast times. Older engines are
the norm, usually Cummins 5.9L,
Duramax 6.6 and Ford 7.3L diesels,
although there are exceptions. Because of
the trend, more and more aftermarket
performance parts have become available,
and there is more demand for performance rebuilding of the common diesel
engines, according to Ron Knoch,
President of the National Association of
Diesel Motorsports (NADM).
“The sale of new trucks has fallen dramatically, however, the shops are reporting very brisk business in repairs, maintenance, and upgrading older diesels,”
Knoch said.
“Most of the trucks in the sport are
used for work during the week, tuned for
pulling and high MPG. During the weekend at the track they tune it for competition and have some fun.” NADM studies
show that owners who race their diesels
on weekends spend about $3500 to add
100 to 400 horsepower to their trucks, on
average. Some are much more involved:
“I know owners who are driving their
trucks for work and have spent easily
$25,000 on top of purchasing their
truck,” Knoch told us. The growing body
of enthusiast racers has generated interest
by traditional performance companies like
Mahle, Crower, ARP, and others, who
made pistons, rods, fasteners and other
lighter, stronger parts.
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LEFT: A broken rocker arm from a 2004
Ford 6.0 diesel. The Ford/Navistar
engines had a redline of 4500 rpm but
the fuel cutoff came at 3600 rpm,
prompting operators to alter the cutoff
level by means of aftermarket programming. Valve train, head bolt and
head gasket failure became common
warranty issues. These engines are still
used in Ford E-series vans, but have
been replaced by the newer 6.4L Power
Stroke on Ford Super duty pickups
since 2007.
RIGHT: Injectors shown are, from
right, Ford Power Stroke 6.0L, GM
Duramax 6.6L and Cummins Bseries 5.9L. Injectors have become
incredibly precise, with tips that
can spray very finely atomized fuel
droplets in precise patterns into
diesel fuel bowls. Computers
direct multiple injections, up to
five per combustion stroke, in
order to promote cleaner combustion and control noise.
BELOW: The underside of a cast
6.6 Duramax piston, showing the
lubrication ports. Narrow piston
skirt extensions are there to promote stability without adding
weight. However, on occasion the
machining around the base of the
tab has removed metal that weakens the tab, allowing it to snap off.
LEFT: Diesel pistons
are generally built
for durability, with
steel inserts protecting the compression ring lands
and two oil control
rings. But with new
emissions laws and
more competition,
every manufacturer
is trying to get
more out of their
engine.
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FEATURE
LEFT: Performance parts for common diesel engines are still in their
infancy, but a number of engine builders are using motorsports to
develop more. The lower piston is a forged Banks Type D piston
made by Mahle. It has valve relief pockets in the top of the piston, a
slightly modified fuel bowl, and Teflon coating on the skirts. Because
it is a pure drag race piston, there is no provision for oil spray cooling on the underside, and weight is cut to a minimum. The stock
piston weighs 853 grams; the forged piston weighs 819 grams.
BELOW: At left is a stock cast rod for a Duramax 6.6L LBZ. At right, a
billet rod made for racing. Even though the stock rods have the latest “fracture split” design, they are only good to 5100 rpm. At 5150,
according to the techs at Banks Performance, they will snap. The
rod at right is 22 grams lighter than the stock rod, and the pin is 40
grams lighter, so there is substantial reduction in reciprocating
weight. The Banks Duramax engine will turn better than 5800 rpm.
Ultra-High Performance
The average weekend warrior is one
thing, but then there is also more professional R&D afoot when it comes to diesel
performance. Recently, new speed records
have been generated in diesel racing,
including new quarter-mile speeds and
elapsed times.
Perhaps most conspicuous among
these would be the Duramax-powered S10 pickup built by Gale Banks
Engineering in Azusa, California. Last
March 8, the dark red S-10 ran 7.77 seconds in a quarter mile, at 180 mph, making it the first diesel pickup to that speed
in the quarter-mile. Although he has
worked with Cummins B motors in the
past to set a diesel land-speed record,
Banks likes the potential of the Duramax
V-8 when it comes to drag racing. “The
Cummins is an older engine, it was
16 APR-JUN 2009 engine professional
designed by Case for agricultural use,” he
told us. The Duramax is a newer design,
and with the right parts, can rev much
higher.
Getting a diesel to rev is something
Banks has done a lot of research on, with
the result that the entire top end of his
race engines are made lighter and
stronger, and the engine breathes better
“with lots of cam and a huge exhaust.”
Forged pistons replace OE cast pistons,
billet rods replace cast rods, and beehive
valve springs with light retainers replace
the stock valve gear. These parts save a lot
of reciprocating weight, but also add
durability. The Banks team has learned
that standard Duramax rods break at
5150 rpm. They have a jar of metal fragments to prove it, and the pieces are very
small.
Otherwise, the race V-8 engine block
is a standard steel 2006 Duramax LBZ
piece, and the steel crank is also from a
standard engine, though it rides on lowfriction bearings.
To Banks, aluminum heads are an
asset, not a problem. “They’re much
more rigid, and lighter.” Noting that gasket retention is more a function of the
number and location of head bolts, he
pulls out a stock GM Duramax gasket
and shows it to me. “Yes, the two metals
expand at different rates. The gasket is
designed for that.” Banks race engines
employ a stock gasket with ARP stud fasteners, which seems to be working fine at
much higher head pressures. The 6.6L
Duramax on the Banks record-setting
pickup can rev to the neighborhood of
6000 rpm. And it runs shockingly clean,
with practically no detectible diesel fuel
smell.
We do it by not over- fueling," tuner
Matt Trainham explains. "We add oxygen
EP 04-2009 10-23:Layout 1 4/17/09 1:34 PM Page 17
Common
Heavy Duty
Engine Facts
Cummins
The Cummins B series is a family of
straight-six diesel engines, first developed
by Cummins and Case Corporation in
1984for agriculture use. The engine is now
widely used in Dodge pickup trucks, buses,
military vehicles, construction equipment
and marine. Those 6BT engines used in
Dodge pickups have Holset turbochargers, a
gear-drive camshaft, deep-skirt engine
block and stout connecting rods. Over 1.5
million of the 5.9 B engines have been
made since 1988.
The original 12-valve B series, appearing in Dodge pickups from 1989, was
updated in 1998 to become the ISB by
adding 24-valve heads and electronic
engine management. The 24-valve is
unusual in that it is a pushrod, 4-valve-percylinder engine.
For the 2003 model year, the Cummins
was fitted with Bosch high pressure common rail fuel injection, increasing power
output. Midway through the 2004 model
year, Cummins 600 was introduced, producing 325 hp 2900 rpm and 600 ft·lbs at 1600
rpm, hence the name. The 610 was new for
the 2005 model year, pushing torque to 610
ft·lbs. Because of the strength of the bottom
end of the engine, strong rods and cast-iron
heads, the 5.9 Cummins is perhaps the
most common powerplant used in diesel
truck racing, accounting for about 75 percent of the entries in some regions of the
country.
The newest Cummins B, the 6.7L,
retains about 45 percent of the original 5.9
components, including the high-pressure
common rail fuel system and electronic
controls. The exhaust valve seats are
Inconel, heads are cast iron and the exhaust
manifold employs a multi-layer gasket. The
connecting rods are forged steel “fracture
split” design. In order to
meet more stringent 2010 emissions
requirements, a cooled EGR system,
variable geometry turbo, high-pressure
direct injection fuel system were added,
along with a particulate filter.
Ford/Navistar
The Ford/Navistar Power Stroke diesels
include the 6.0L and 6.4L engines commonly found in Ford Super duty pickups. These
replaced the 7.3L Power Stroke for the
2003 model year. Early 6.0L diesels were
unreliable, creating warranty issues at Ford
and a legal dispute with Navistar. After many
running changes to the engine, the reliability
of the later 6.0L engines was considered
good, although few are seen in motorsports
applications and performance parts are
scarce. The 6.0L diesel was used in Super
Duty pickups from 2003 to 2007, and in
Ford E-series vans through the 2009
model year.
The 6.0L was replaced by the 6.4L for
the 2007 model year when new diesel
emissions standards took effect. By use of a
twin-turbo system that stages two differentsize turbos in sequence, the 6.4 makes 350
hp at 3000 rpm and 650 lb/ft of torque at
2000 rpm. Like all the newer diesels, it
must run on ultra-low-sulfur diesel (ULSD)
and use CJ-4 lubricants for soot control.
Caterpillar
The Caterpillar 7.2L C7 shares a common
block with the Caterpillar 3126. It is turbocharged. The engine is available with ratings from 190-330 hp and offers a torque
range of 520-860 lb-ft. The C7 uses the
HEUI (Hydraulic-Actuated Electronic Unit
Injector) fuel system. Cat diesels up to the
12.5L, 380-430hp C13 are commonly seen
in motor home applications and Top Kick
medium
duty trucks. There are electronic tuning
boxes available for this engine and other
agricultural diesels that are designed to
improve mileage and/or towing power.
GM/Isuzu Duramax
GM/Isuzu Duramax engines were made in
Moraine, OH, the product of a joint venture
between GM and Isuzu. Although GM has
sold its stake in Isuzu, the plant continues to
manufacture some 200,000 diesel V-8
engines a year, and the 1 million mark was
passed in May of 2007. These 6.6-liter
diesels include the LB7 (2001 to 2004), the
LLY (2005), the LLY (2006), and the LBZ
(2006.5 to 2007.5). These engines were
used in the medium-duty Topkick and
Kodiak trucks, Silverado and Sierra HD pickups. Later versions appeared in the Hummer
H1 Alpha and GM Savanna and Express
vans. All were turbocharged, 32-valve V-8s
with high-pressure common rail direct injection and aluminum cylinder heads. The latest Duramax 6.6, the LMM, is essentially an
LBZ with emissions equipment, requiring
ultra-low-sulfur diesel and CJ-4 low-ash
lubricants.
Prior to 2001, GM 6.2L and 6.5L diesels
were made by Detroit Diesel, and were
optional in 1982 through 2000 GM pickup
trucks, Suburbans, Tahoes, and GM vans.
They are a substantially different engine
than the GM/Isuzu, with a different block.
They were also widely used by the military,
in motor homes, and as conversion engines
in heavier four-wheel-drive vehicles such as
Land Rovers.
engine professional APR-JUN 2009 17
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FEATURE
RIGHT: Piston-to-valve clearances need to be carefully checked when preparing a diesel race motor,
which may have a resurfaced head and be subject
to valve protrusion. This stand allows the heads to
be fitted with light test springs, so the entire
assembly can be cycled through for accurate measurements.
BELOW: “Beehive” valve springs and matched
retainers are all part of the formula when building a
higher-revving diesel.
LEFT: Bottom end components on most diesels are
likely to be good enough for
long life and even performance use. In this race application, a stock bearing cap
is combined with ARP studs
that can be precisely preloaded by cycling the studs
three times before final
torque. With this procedure,
the studs can better resist
higher cyclic loads.
in proportion with fuel using two turbos
and nitrous. It keeps EGTs down, keeps
mileage up, and makes really good power.
Our air/fuel ratio, 28:1, is leaner than that
of most stock trucks.”
Banks disagrees with the idea that
diesels weren’t made to be modified.
“There is a lot of tribal lore on the subject,” he says with some regret. His customers range from motor home owners to
average Joes with pickup trucks, to military, marine, and heavy duty commercial
fleets, such as Wal-Mart. The company
leverages racing experience to develop
parts to improve mileage and durability.
Much of the equipment is designed to
improve cooling to lower exhaust gas
temperature, allowing for durability even
in an environment of greater fuel supply.
It’s accomplished by adding better intercoolers and better air intake capability,
including more efficient turbos, plus the
18 APR-JUN 2009 engine professional
appropriate engine management. Banks
runs a number of emissions dynos on his
company campus, making sure that the
parts he develops for street use do not
compromise federal regulations.■
SOURCES • Gale Banks Engineering,
546 Duggan Avenue, Azusa, CA 91702.
800.601.8072, www.bankspower.com;
• Dugas Engine Service, 1748 Delasalle Dr,
New Iberia, LA 70560. 337-365-1140;
• Harry’s Machine Works, 407 W McArtor Rd,
Dodge City, KS 67801. 620-227-2201;
• Manitowoc Motor Machining, 2308 Franklin
Street, Manitowoc, WI 54220. 920-684-8577,
www.motormachining.com;
• National Association of Diesel Motorsports
(NADM), 866-RUN-NADM, www.runnadm.com;
Automotive Racing Products (ARP),
1863 Eastman Ave, Ventura, CA 93003,
805.339.2200, www.ARPdiesel.com.
John Stewart has been an automotive
journalist and technical writer since
1977. When he is not writing car
reviews for newcartestdrive.com,
popularmechanics.com or Four Wheeler
Magazine, John Stewart works on
restoring his 1980 BMW boxer twin
motorcycle at his home in Pasadena,
California. If you have any questions,
comments or concerns, please
call 626-403-0545 or e-mail:
[email protected].