 |
| |
Buy with confidence!
If for any reason
you're not
completely satisfied
with an item, simply
return it within 7
days and the
purchase price will
be refunded.
|
|
 |
|
|
We ship world wide.
All international
orders must be paid
online. Checks or
money orders
drawn on non-US
banks will not be
accepted.
|
|
|
|
|
Choosing the Right Cylinder Heads
|
|
|
|
An engine’s cylinder head ports are the pathways to power! The air and fuel that pass through
them are the sole source of energy. No matter what standard you apply to engine performance—
horsepower, torque, fuel eco- nomy, or response—it is the valves, seats, and ports that are finally
responsible for how well the motor works.
Differences between high-performance short blocks are relatively minor; what makes one motor
superior to another is likely to be the valve layout, chamber shape, and port volumes.
No book can thoroughly explain the mysteries of cylinder head porting. Porting techniques are as
trendy as hairstyles and musical tastes; yesterday’s hot setup is today’s old news. First of all, the
design qualities of available head castings have a tremendous impact on what is possible and what
is not. And with both the Detroit automakers and the specialty head manufacturers introducing
radical new designs and revisions of old ones almost daily, the state of the art in head porting is
constantly changing. For these reasons, we will concentrate on the basic blueprinting techniques
that apply to any cylinder head: Preparing the valves, seats, guides, and springs. And for those
who have a compulsion to grind on cylinder heads, we will outline some simple port work that can
make a substantial difference in airflow.
|
|
|
 |
|
 |
|
|
|
The range of cylinder head choices confronting performance enthusiasts has never been
greater. Today an engine builder can select from a variety of factory and aftermarket castings in
both aluminum and iron.
|
|
|
|
Selection and Inspection
Selecting and inspecting cylinder heads parallels very closely the steps involved in choosing a
cylinder block. Many of the same procedures and cautions apply.
In general, late-model cylinder heads are inferior to older, Sixties vintage iron. Current production
castings have very thin metal sections, and the ports are likely to be extremely restrictive. These
small runners promote high mixture velocities, even at low engine speeds, so they are favored by
mileage-conscious automakers. Power, though, comes with an increase in port volume—which is
why you must go back to the ample passages found in older cylinder heads if you are building a
serious street performance or bracket-racing engine.
For an all-out racer, however, nothing less than the very latest factory or specialty castings will do.
The series of “Bow Tie” cylinder heads developed by Chevrolet, the SVO offerings from Ford, and
even the so-called “corporate” small-block heads (for the Chevrolet cylinder block) available from
Pontiac all represent the latest thinking in the science of engine airflow. And when both your budget
and the rulebook allow specialty castings, the racing-only designs from Dart, Brodix, Brownfield,
and other non-Detroit sources are vastly superior to anything you can find in a salvage yard.
|
|
|
If your head choices are confined to used parts, then you must look carefully before exchanging
cold cash for cast iron. Cylinder heads, like blocks, are prone to cracking if they have been
overheated or frozen during their lifetime. The advent of unleaded gasoline in the early Seventies
prompted many automakers to induction-harden the valve seats in cylinder heads. This allows the
seats to survive without the lubrication provided by small amounts of lead—but this process also
made the seats much more susceptible to cracks, especially on the hot exhaust side. This is
another point in favor of early “pre-smog” head castings. Cylinder heads can be checked for cracks
with Magnaflux inspection or by pressure testing the water jackets, as discussed in the chapter on
cylinder blocks.
A thorough head inspection should also include a close look at the valve seats and guides. If you
have a choice, avoid heads that have already had a valve job performed on them. During a typical
quick-and-dirty valve job, the seats are ground with little concern for airflow characteristics. The
usual result is that the valves are “sunk” in the chambers. This reduces compression, by increasing
the combustion chamber volume. In addition, the bumps and ridges left around the seat by a
careless machinist can disrupt the flow of air around the valve head. It may be difficult to find this
telltale evidence of a previous valve job in a cylinder head that is coated with baked-on carbon.
When you go head hunting, take along a valve spring compressor and remove several valves. If
you find distinct ridges surrounding the seats, chances are good that someone has already worked
over—and perhaps ruined—the castings.
|
|
|
A sharp parting line around a seat indicates that at some time in the past it has been repaired with
an insert. An insert is a metal ring that is pressed into the head to repair a damaged or cracked
seat. There is nothing intrinsically bad about a seat insert; after all, most aluminum heads are
outfitted with seat inserts at the factory. However, you have no way of knowing if the insert was
installed properly or what type of damage it conceals. Unless the casting in question is extremely
rare or valuable, it is probably better to continue your hunt than to buy someone else’s problems.
A little preliminary research can make your head shopping more successful. Every brand of
performance engine has some prized head castings. For example, small-block Chevrolet
enthusiasts seek out “fuel-injection,” Bow Tie, and “turbo” castings; Mopar fans covet various
W-2 and Stage heads, while the Ford contingent stalks Boss and Cleveland components.
|
|
|
Unfortunately, a reputation for high performance is likely to add a premium to the price of a set of
cylinder heads. You can, however, cut the high cost of hot rodding by recognizing that the real
distinction between a set of high-priced heads and cheaper castings may be only an insignificant
difference in valve sizes or combustion chamber volume.
Among small-block Chevy head castings, for example, the early large port heads with 2.02-inch
intake valves—usually identified as “fuel-injection” heads—can fetch twice the price of a pair of
similar castings with 1.94-inch intakes. In truth, the heads with smaller valves are really the better
buy. They have the same ports and chambers as the big-valve castings. And if you upgrade them
by installing larger valves, your machinist will have virgin metal to work with when he grinds the
critical valve seats. This is just one instance of smaller being better—and a bargain, too.
|
|
|
Cylinder Head Selection
In 1997, the number of cylinder heads available for your engine was staggering, and the numbers
of choices were a little intimidating. Cylinder head design, particularly for high performance and
race heads, has ranged far from the factory performance castings of the Sixties and Seventies.
Older designs with their attendant limitations and problems have been improved upon
tremendously. Aluminum and cast iron performance heads are available in many port volumes
sizes, valve sizes, port configurations, valvetrains, combustion chamber sizes and designs, spark
plug locations, water jacket locations, spring pocket dimensions, and deck surface thicknesses, and
they have better oil and gasket sealing.
Many of the blueprinting and performance-enhancing techniques in cylinder head preparation have
been adopted into the newer design racing and street performance heads. These days, you get
more cylinder head for your money, more power, less cost, and wider consumer availability. Many
reputable specialty cylinder head shops can prepare heads, flow bench test them, and assemble
them with the valvetrain parts you need. “Swirl and Tumble” head technology has even found its
way into street head designs, not only to improve cylinder filling and power, but also to reduce
tailpipe emissions levels.
|
|
|
One aspect that many of us have to consider is cost. You can certainly use an older style casting
and make improvements in port flow, valve size, valvetrain parts, etc. However, you may need to
install hardened valve seats to the heads if you are going to use unleaded pump gasoline. By the
time you add up the costs of these improvements and include the costs of head cleaning, repairs,
seat grinding, guides, install screw-in rocker arms, seals, etc., the costs may surpass the cost of a
newer design head that has already incorporated these improvements. Give it some thought before
you make your cylinder head choices.
|
|
|
 |
|
|
|
Edelbrock Performer aluminum
heads offer good value for those
seeking a more modern design street
performance head. When you
consider the time and money spent
altering an older style production
cast iron head, the newer designs
are comparable in price, but you get
more cylinder head for your money
with the newer designs.
|
|
|
|
|
|
Previous | Next
|
|
|
|
|
|
|
|
|
|
|
|
|
This has been a sample page from
|
|
|
|
|
 |
|
The Step-By-Step Guide to Engine Blueprinting
by Rick Voegelin
|
|
|
|
|
Practical Methods for Racing and Rebuilding
How to buy machine shop work
Selecting and preparing parts
|
|
|
|
|
|
This completely revised and updated version containing an
additional 32 pages is simply the best book you can buy on
engine preparation for street or racing! Rick Voegelin's highly
acclaimed combination of savvy writing and wrenching skills puts
this best-seller in a class by itself. All important preparation
techniques are clearly illustrated and explained in this easy-to-
read text. Engine Blueprinting shows the reader how to use
precision measuring tools, calculate compression ratios, degree a
camshaft, and much more! Loaded with helpful advice, this book
should be in every enthusiast's tool box.
|
|
|
Click below to view sample
pages from each chapter.
|
|
|
|
|
|
"Rick Voegelin's book, The Step-by-Step Guide to Engine
Blueprinting, is an excellent source of performance-oriented
engine building information for the beginner and the seasoned
veteran alike. This digest should be in every enthusiast's greasy
mitts."-- Steve Magnante, HOT ROD
|
|
|
Chap. 1 - Engine Blueprinting
Chap. 2 - Cylinder Block
Chap. 3 - Crankshaft
Chap. 4 - Connecting Rods
Chap. 5 - Pistons
Chap. 6 - Cylinder Heads
Chap. 7 - Camshaft
Chap. 8 - Compression Ratio
Chap. 9 - Balancing
Chap. 10 - Assembly Tips
|
|
|
|
|
|
Softbound
8-3/8 x 10-7/8
160 pages
400 b/w photos
Item #SA21
Price: $18.95
|
|
Click here to buy now!
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
|
|
|
How to Rebuild the Small-Block Ford
This 144 page book guides you step by step through a rebuild,
including: planning, disassembly and inspection, choosing the
right parts, machine work, assembling your engine, first firing and
break-in. It also gives you helpful hints and tips on performance
upgrades, including cams, heads, ignition, induction, and more. It
also points out problem areas to watch for, professional builder
tips, jobs that need special care or special tools, and more.
Includes 495 color photos and covers the Ford 289, 302, 351W,
351C, 351M and 400.
|
|
Price:
$22.95
|
|
|
 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Turbochargers
How to select and install the correct turbo for big or small
horsepower gains. Discusses turbocharger design, sizing,
matching, controls, carburetion, exhaust, ignition,
intercooling, marine and high altitude applications. The most
comprehensive book available. Turbo suppliers and kit
maker addresses are included. “Everything you could possibly
need to know about turbochargers for automotive applications
is in this book.
|
|
|
 |
|
|
Price:
$18.95
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
How to Build Big-Inch Ford Small Blocks
By increasing the bore and stroke of your current engine, you can
add those cubic inches without the hassle of switching to a big
block. George Reid thoroughly explains the building of a small
block Ford stroker, paying special attention to the effect that
increasing the bore and stroke have on the engine as a whole.
Also included is a complete guide to factory head and block
castings, as well as aftermarket block and head guides, so you
can choose exactly the right parts for your project.
|
|
|
 |
|
|
Price:
$18.95
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
|
|
|
 |
|
 |
|
 |
|
|
Payment, Shipping & Sales
Tax: Iowa
residents must pay 7% sales tax. Items usually ship
within one
business day of receipt of payment! Standard shipping is a flat rate of
$4.95 to
anywhere in the United States with USPS Media Mail.
Priority Mail shipping is available for an
additional $2.95, or
$7.90 for shipping. Shipping is combined and discounted for multiple item
purchases as follows: first item regular shipping price, add
$1.95 for each additional item. For
purchases of 3 or more items
shipping is automatically upgraded to Priority for no additional
charge! We offer world wide shipping and ship to Canada and Mexico
with USPS Priority Mail
International for $11.95, and to most
locations in Europe, Australia, Asia, Japan and South
America for
$14.95. Satisfaction is Guaranteed. Our store has a NO HASSLE RETURN
POLICY
within 7 days of purchase.
|
|
|
|
|
|
 |
|
|
|
|
|
|
|
|
|
|
