2011 - Crane Cams

CAMSHAFTS
Chevrolet Small Block V8 Tech Tips & Notes
1957-1987 262-400 V8 (262-265-267 (4.4L)-283-
302-305 (5.0L)-307-327-350 (5.7L)-400 cu.in.)
The classic Small Block Chevrolet V8 was introduced in
1955, in a 265 cu.in. version. The 1955-56 265 engines
required a camshaft having a flat machined on the rear cam
bearing journal to allow for oil flow to the lifter galleries
and the top end. If you are using one of these blocks, a flat
must be machined in center of the rear cam journal, .350”
wide and .080” deep. Another option would be installing
later model cam bearings in these early blocks. If your camshaft
already has a flat on the rear journal, it will not cause
any oiling problems if used in a later engine.
The entire family of engines, designated by Crane Cams’ 11
prefix (except the Energizer line of camshafts), were
equipped from the factory with flat faced lifters, either
hydraulic or mechanical, throughout their production run.
We offer complete lines of hydraulic, hydraulic roller,
mechanical, and mechanical roller camshafts, lifters, and
valve train components for these. Although we list this
engine family as running through 1987, some truck applications
continued through 1995. It’s important to verify the
engine type when dealing with these vehicles to insure the
proper components are being obtained.
Cast hydraulic and mechanical lifter camshafts are available
with standard cam bearing sizes, and also optional
Chevrolet Big Block bearing sized journals (1.948” dia.), indicated
by a BB suffix in the grind number. The standard firing
order is 1-8-4-3-6-5-7-2, and cast standard journal camshafts
can also be ordered with our SFO suffix firing order
configuration of 1-8-7-3-6-5-4-2.
Crane Cams’ retrofit hydraulic roller and mechanical roller
camshafts are produced from steel billet material, heat
treated, and finish ground in a variety of versions. Our retrofit
hydraulic roller lifters do not require any block machining,
and are a drop-in configuration, incorporating a vertical
locking bar. For street and endurance applications, we offer
camshafts equipped with a cast iron distributor drive gear
and rear journal installed on the steel camshaft. These are
noted by an IG suffix (Iron Gear), allowing the use of a standard
type distributor gear for long term reliability.
There are many journal size options available for the roller
camshafts, including: Standard (1.868”); Roller Bearing
(1.875”) – RB suffix; Big Block (1.948”) – BB suffix; Large
Roller Bearing (50mm/1.969”) – LRB suffix; 55mm (2.165”)
–55J suffix. Other sizes are available on request. Camshafts
with larger then stock journals have a step ground on the
front journal, so a standard size camshaft sprocket can be
used.
We offer camshafts with different lobe layouts for the various
cylinder head options that can be installed on these
engines. On this page are drawings illustrating the standard
Small Block, Dart Buick/Chevrolet Splayed Valve (84 – prefix),
and Chevrolet SB2 (138 – prefix) cylinder head valve
layouts that are primarily in use today.
Standard, SFO (1-8-7-3-6-5-4-2), and SFO1 (1-8-7-2-6-5-4-3)
firing orders are offered, along with other custom options
54
FRONT
FRONT
FRONT
CRANECAMS.COM
E I I E E I I E
Standard 11-Prex
E I E I E I E I
I
Dart Buick/Chevrolet Splayed Valve 84-Prex
E I E E I E I
SB2 138 and 123 - Prexes
for 180 degree crankshafts and other unique situations.
Drilling and tapping the rear cam journal for the Sander
accessory drive is offered (RD – suffix), as is gun drilling of
the camshaft for lightness and reduced torsional deflection
(DR – suffix). For certain usages, we offer special lightweight
camshafts (LW – suffix) having undercut bearing journals,
narrow lobes, and gun drilling where weight saving is of
prime importance.
1987-1999 305 (5.0L)- 350 (5.7L) V8
This first major upgrade to the traditional Small Block V8
incorporated a hydraulic roller camshaft and lifters. These
are sometimes referred to as Vortec engines when checking
some reference materials. The bolt pattern on the front of
the camshaft was reduced in diameter, allowing for a step
on the front journal, permitting the installation of a thrustplate
to control camshaft endplay.
This engine family is referred to as Crane Cams’ 10-prefix,
and our early steel billet camshaft cores did not incorporate
provisions for the front ignition drive that was later used on
the 1992-1997 LT-1 and LT-4 engines.
We have separated these engines from the LT-1 & LT-4 versions
in this catalog to properly define the emissions legalities
of the camshafts, although they will now physically
interchange. Since the late 90’s, all of our camshafts for
these powerplants have been machined for the front ignition
drive and include the long cam dowel pin that’s also
needed. If you have an engine that does not require the
long dowel pin, you can drive the pin in further to the proper
length for your application.
The lifter bores on these blocks were increased in height to
accommodate the hydraulic roller lifters. When using a camshaft
with greater than standard lobe lift, or a small base
circle cam, you must use taller-than-standard lifters to prevent
them dropping out of the factory alignment bars
when on the base circle. Our 10535-16 hydraulic roller lifters
are intended for these purposes. Our vertical guidebar
11532-16 retrofit hydraulic roller lifters are also suitable for
these applications.
We also offer mechanical roller lifter camshafts and components
for these engines, in either standard or Iron Gear
configurations.
REAR
REAR
REAR