©2010 Edelbrock LLC
Brochure #63-0170
Part #1801-1806,1812, 1813, 1825, 1826
Rev. 6/10 - AJ/mc Page 1 of 6
PLEASE study these instructions carefully before beginning this installation. Most installations can be accomplished with common tools and
procedures. However, you should be familiar with and comfortable working on your vehicle. If you do not feel comfortable performing this installation,
it is recommended to have the installation completed by a qualified mechanic. If you have any questions, please call our Technical Hotline at:
1-800-416-8628, 7:00 am - 5:00 pm, Pacific Standard Time, Monday through Friday.
IMPORTANT NOTE: Proper installation is the responsibility of the installer. Improper installation
will void your warranty and may result in poor performance and engine or vehicle damage.
DESCRIPTION: Edelbrock Thunder Series AVS carburetors have been calibrated, factory flow-tested, and preset. These instructions also apply to
carburetors featuring our EnduraShine™ finish. Please read all instructions prior to installation. For "Theory of Operation" and "Tuning Procedures",
see the accompanying carburetor Owner's Manual. These are non-emissions carburetors, check your local emissions laws.
ATTENTION: EDELBROCK CARBURETORS ARE NOT CALIBRATED FOR OR COMPATIBLE WITH ALCOHOL RACE FUEL OR E85 PUMP FUEL.
USE OF ALCOHOL OR E85 IN YOUR EDELBROCK CARBURETOR WILL DAMAGE YOUR CARBURETOR AND VOID YOUR WARRANTY. THESE
FUELS CAN ALSO DAMAGE OTHER FUEL SYSTEM COMPONENTS, UNLESS SPECIFICALLY DESIGNED FOR USE WITH ALCOHOL FUELS.
NOTE: Edelbrock Thunder Series carburetors are not for computer-controlled applications. That includes some 1981 & later GM
vehicles with Q-Jet carburetor and some 1981 & later Ford vehicles with automatic overdrive (AOD) transmissions.
SPECIAL NOTE (1803 & 1804): These 500 CFM carburetors are calibrated for out-of-the-box performance on dual-quad applications ONLY. For
single-carb applications, you should use carburetor 1801 or 1802. If you already have carburetor 1803 or 1804 you can recalibrate the carburetor
prior to use. Calibration Kit #1486 contains all jets and rods necessary to recalibrate 1803 or 1804 carburetors. Edelbrock has found the following
to be a good starting point for most performance applications requiring a 500 CFM carburetor:
Primary Jet .086” (Factory setting)
Primary metering rod .065” x .052” (#1460)
Secondary Jet .095” (#1426)
Air Valve Secondary Setting 1-1/2 Turns (See Fig. 12, Page 6)
❑ 1 1/4" NPT pipe plug
❑ 1 Throttle cable ball end stud
❑ 1 10-32 Hex nut
❑ 1 3/16” Internal star washer
❑ 1 Red choke positive wire
(Electric choke carburetors only)
❑ 1 Black choke ground wire
(Electric choke carburetors only)
❑ 4 5/16” SAE flat washers
(EnduraShine™ finish only)
❑ 1 Installation instruction sheet
❑ 1 Owner’s Manual
❑ 1 Warranty card
❑ 1 Square-bore base gasket
❑ 1 Air horn gasket
❑ 1 Air cleaner stud
❑ 2 5/32” Vacuum caps
❑ 1 5/32” Vacuum “T”
EDELBROCK THUNDER SERIES AVS CARBURETORS
Part #1801, 1802, 1803, 1804, 1805,
1806, 1812, 1813, 1825, 1826
INSTALLATION INSTRUCTIONS
❑ Replace fuel filter. Dirt (i.e. corrision residue or other debris)
found in carburetor voids warranty.
❑ Check and replace the air filter, if necessary.
❑ Check PCV valve and replace, if clogged.
❑ Check all hoses for leaks or cracks and replace, if necessary.
❑ Check fuel pump for proper operation and replace, if necessary.
❑ Check the intake manifold and cylinder head gaskets for leaks and
replace, if necessary.
❑ Check the ignition system: clean and gap or replace spark plugs,
plug wires, and adjust ignition timing.
CHECK THE FOLLOWING BEFORE BEGINNING INSTALLATION
WARNING: WHEN WORKING AROUND GASOLINE, ALWAYS WORK IN A WELL VENTILATED AREA, AND KEEP ALL OPEN FLAMES, SPARKS AND
OTHER SOURCES OF IGNITION AWAY FROM THE WORK AREA. FAILURE TO DO SO CAN RESULT IN A FIRE OR EXPLOSION.
KIT CONTENTS