Edelbrock 61949 Installation Instructions - page 2
©2008 Edelbrock Corporation
Brochure #63-0414
Catalog #61949, 61969, 61979, 61989
Rev. 12/08 - AJ/mc
Page 2 of 2
ROCKER ARMS AND VALVE TRAIN: These cylinder heads are designed
to use the stock rocker arms or aftermarket replacement rocker arms
designed for the Gen III and Gen IV engines. Aftermarket stud &
guideplate rocker arm conversions require machine work to the
rocker stud pad for proper guideplate placement. Due to the larger
intake port design on these CNC-ported heads, the factory rocker bolts
will need to be shortened, or you may use aftermarket rocker bolts.
VALVE COVERS: Edelbrock Performer RPM cylinder heads will accept
stock center-bolt design valve covers. Engines originally equipped with
perimeter bolt valve covers will need to convert to center bolt valve
covers. Perimeter bolt cylinder heads are found on 1997, 1998, and
some 1999 vehicles.
INTAKE MANIFOLD: Cylinder Heads will accept stock intake manifolds,
as well as our Performer RPM LS-1 Carbureted intake manifold #7118,
Victor JR. LS-1 Carbureted intake manifold #2908, or Victor Jr. LS-1 EFI
intake manifold #29085 (requires fuel rail kit #3638 or equivalent). Use
stock type LS1/LS6 individual port o-ring seals.
EXHAUST HEADERS: For optimum performance, exhaust headers and a
low restriction exhaust system are highly recommended for use with
Edelbrock Cylinder Heads. Exhaust ports are CNC-profiled to match
stock or Edelbrock #6962 exhaust gaskets which are recommended for
this application.
SPARK PLUGS:
Use 14mm x 17.5mm (.708”) reach tapered seat
resistor type spark plugs.
Heat range requirements will vary by
application. For many applications, GM factory spark plugs or equivalent
spark plus such as Champion RS14YC6, NGK TR55, or Denso IT16 spark
plugs may be used. Use anti-seize on the plug threads to prevent
galling in the cylinder head, and torque to 10 ft./lbs. Do not over
tighten sparkplugs! If a short reach plug is used, poor
performance and possible engine damage may occur.
INSTALLATION:
Installation is the same as for original equipment
cylinder heads. Consult a factory service manual for specific procedures,
if necessary. Factory manuals can be purchased direct from Helm® at:
www.helminc.com. Be sure that the surface of the block and the surface
of the head are thoroughly cleaned to remove any oily film before
installation. Use alcohol or lacquer thinner on a lint-free rag to clean.
NOTE: Be VERY careful to remove any coolant or other fluids that
may be in the cylinder head bolt holes in the block. These bolt holes
are sealed at the bottom, and any fluid trapped in the holes will
cause the block to crack when you torque the bolts.
When using the GM factory head bolts, be sure to replace all of the bolts
with new bolts, and to follow the factory recommended installation
procedures. The factory bolts and installation procedures do not call for
the use of oil or any lubricant on the threads. When using aftermarket
bolts or studs, follow the manufacturer’s recommended torque
specifications
(See Figure 1 for factory tightening sequence).
NOTE: A Torque Angle Gauge is required for proper installation.
Torque to yield fasteners are not designed to be re-torqued after
installation.
When using Edelbrock bolt kit #8596 or #8595, lightly coat all head
bolts with 30wt motor oil or ARP moly lube, then substitute a final
torque value of 85 ft/lbs (or 70 ft/lbs w/ ARP moly lube) for the M11
bolts, and 29 ft/lbs (or 23 ft/lbs w/ ARP moly lube) for the M8 bolts.
SPECIFICATIONS:
Head Bolt Torque:
See Figure 1, or use head bolt
manufacturer’s specifications
Deck Thickness:
5/8”
Combustion Chamber Volume:
65 cc
Valve Size:
Intake - 2.02”
Exhaust - 1.57”
Valve Seats:
Hardened ductile iron, non-
interlocking, compatible with
unleaded fuel
Valve Spring Diameter:
Beehive type spring,1.300”
at base of spring
Valve Spring Installed Height:
1.800”
Valve Spring Seat Pressure:
130 lbs. @ 1.800”
Valve Spring Open Pressure
318 lbs. @ 1.200”
Max. Valve Lift:
.650”
Coil Bind
1.085”
15 13 11 12 14
10 3 1 5 9
7 6 2 4 8
Figure 1 - Factory Cylinder Head Bolt Torque Sequence
First Design Blocks
(8 long, 2 medium length M11 bolts per cylinder head)
First Pass:
Torque all M11 bolts (1-10) in sequence, to 22 ft./lbs.
Second Pass:
Turn all M11 bolts (1-10) in sequence, an additional
90 degrees.
Final Pass:
Turn all long M11 bolts (1-8) in sequence, an
additional 90 degrees.
Turn medium M11 bolts
(9-10) an additional 50 degrees. Tighten M8 bolts
(11-15) in sequence shown to 22 ft./lbs.
Second Design Blocks
(10 long, M11 bolts per cylinder head)
First Pass:
Torque all M11 bolts (1-10) in sequence, to 22 ft./lbs.
Second Pass:
Turn all M11 bolts (1-10) in sequence, an additional
90 degrees.
Final Pass:
Turn all M11 bolts (1-10) in sequence, an additional
70 degrees. Tighten M8 bolts (11-15) in sequence
shown to 22 ft./lbs.
NOTE: First to Second design change-over date is roughly mid
December 2003 for block manufacturing date. Always refer to your
vehicles service manual for specific torque procedures.
(EXHAUST PORT SIDE)
Edelbrock Corporation • 2700 California St. • Torrance • CA 90503
Tech Line: 800-416-8628 • Office: 310-781-2222
E-Mail: Edelbrock@Edelbrock.com