PERFORMANCE
GM
PARTS
ZZ572/620 (12499190) and ZZ572/720R (12498825) Short Block Specifications
Thank you for choosing GM Performance Parts as your high performance source. GM Performance Parts is
committed to providing proven, innovative performance technology that is truly.... more than just power. GM
Performance Parts are engineered, developed and tested to exceed your expectations for fit and function. Please
refer to our catalog for the GM Performance Parts Authorized Center nearest you or visit our website at
www.gmperformanceparts.com.
This publication provides general information on components and procedures that may be useful when installing
or servicing a ZZ572 short block assembly. Please read this entire publication before starting work. Also, please
verify that all of the components listed in the Package Contents section below were shipped in the kit.
The information below is divided into the following sections: package contents, torque information, ZZ572/620 and
ZZ572/720R short block assembly specifications, and a service parts list.
The ZZ572 short block assembly incorporates modern technology in a package that can be installed in applications
where 366cid and larger displacement Big Block Chevrolet (BBC) V-8s were originally used. This short block is
assembled using brand new, premium quality components. Due to the wide variety of applications in which a ZZ572
short block assembly can be used, some procedures and recommendations may not apply to specific applications.
The ZZ572 short block assembly in an all new Gen VI Tall Deck Bow Tie Cylinder Block manufactured on new
production tooling; consequently you may encounter dissimilarities between the ZZ572 tall deck BBC short block
assembly and previous versions of the BBC V-8. In particular is the fact that the ZZ572 tall deck BBC short block
assembly in a "Tall Deck", meaning the distance from the crankshaft centerline measured perpendicular to the deck
surface is 10.2" or .400" greater than a "Short Deck" BBC (9.8"). This increase may cause interference in some
applications where a short deck BBC was previously installed. Also, the ZZ572 engines are internally balanced and
only should be used with internally balanced flywheel, flexplates, and harmonic dampers. In general, items such
as motor mounts, bell housing, starters, etc. can be transferred to this ZZ572 tall deck BBC short block assembly
when it is installed in a vehicle originally equipped with a BBC V-8 engine. However, such items as intake manifolds,
headers, push rods, etc. are different. These differences may require modifications or additional components not
included with this ZZ572 tall deck BBC short block assembly. When installing a ZZ572 tall deck BBC short block
assembly in a vehicle not originally equipped with a BBC V-8 it may be necessary to adapt or fabricate various
components for the cooling, fuel, electrical, accessory drive system and exhaust systems.
It is not the intent of these specifications to replace the comprehensive and detailed service practices explained
in the GM service manuals.
For information about warranty coverage, please contact your local GM Performance Parts dealer.
Observe all safety precautions and warnings in the service manuals when installing a ZZ572 tall deck BBC short
block assembly in any vehicle. Wear eye protection and appropriate protective clothing. Support the vehicle
securely with jackstands when working under or around it. Use only the proper tools. Exercise extreme caution
when working with flammable, corrosive, and hazardous liquids and materials. Some procedures require special
equipment and skills. If you do not have the appropriate training, expertise, and tools to perform any part of this
conversion safely, this work should be done by a professional.
ZZ572/620 and ZZ572/720R Short Block Specifications REV 15JA08
TITLE
ALL INFORMATION WITHIN ABOVE BORDER TO BE PRINTED EXACTLY AS SHOWN ON 8 1/2 x 11
WHITE 16 POUND BOND PAPER. PRINT ON BOTH SIDES, EXCLUDING TEMPLATES.
TO BE UNITIZED IN ACCORDANCE WITH GMSPO SPECIFICATIONS.
Specifications Part Number 88962927
DATE
07OC03
Initial Release - Shawn Smith
16FE07
Revised - Rusty Sampsel
GENERAL MOTORS
SERVICE PARTS OPERATIONS
6200 Grand Pointe Drive, Grand Blanc, MI 48439
88962927
PART NO.
REVISION
1
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