Cloyes Hex-A-Just 9-3152A (Viper 3 Bolt) User Manual

Cloyes For the car

Installation Instructions

9-3152A Hex-A-Just® Roller Timing Set

BEFORE YOU BEGIN: READ ALL OF THESE INSTRUCTIONS FIRST !!!

Note: The 9-3152A Hex-A-Just

timing set is not a direct bolt-on application. Machining is

required on the nose of the camshaft prior to installation. The following information explains
the modifications that must be made to the camshaft prior to assembly.

Camshaft Modification. The Viper production engine cam sprocket (OEM P/N 5245124) is
a single bolt installation design with a dowel pin for alignment. In order to apply the Cloyes
Hex-A-Just

system to the Viper engine, a 3-bolt pattern was incorporated into the design of

the high performance cam sprocket (S170DA). The camshaft modification requires three bolt
holes to be drilled and tapped into the nose of the camshaft. Below is a diagram illustrating
the dimensions and angular locations of the bolt holes.

As seen from the diagram, the position of the bolt holes is dependent upon the outer
diameter of the camshaft and the center of the dowel pin. They are centered around a
1.0310” bolt circle diameter and are equally spaced 120° apart. The angular location of the
bolt holes to the dowel pin is very important. Each bolt hole must be within .0050” of true
position, and they should be threaded at least .750” deep.

Ø1.0310

FRONT VIEW OF

CAMSHAFT NOSE

60°15'
59°45'

120°15'
119°45'

60°15'

59°45'

120°15'
119°45'

5/16-18 UNC BOLT HOLES
TYPICAL 3 PLACES

CAMSHAFT

DOWEL PIN

ORIGINAL BOLT HOLE
(NOT USED)

CENTERLINE OF DOWEL PIN

(MUST BE WITHIN .0050"
OF TRUE POSITION)

BOLT CIRCLE