Edelbrock 3847/3 Installation Instructions
Catalog #s 3847, 38473, 3848, 38483, 3849, 38493, 3850, 38503
3851, 38513
Rev. 3/08 - AJ/mc
©2008 Edelbrock Corporation
Brochure #63-3847
Page 1
Thottle Body Elbow
For EFI Manifolds w/ 4150 flange
Catalog #s: 3847/3, 3848/3, 3849/3, 3850/3, 3851/3
INSTALLATION INSTRUCTIONS
®
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 or e-mail us at Edelbrock@Edelbrock.com.
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 Throttle Body Elbows are designed to allow mounting a throttle body in a conventional position when using EFI manifolds,
such as the Edelbrock Victor and Super Victor EFI series, equipped with a 4150 square-bore carburetor flange. All elbows are compatible with Edelbrock
LS2 and Ford 5.0L based throttle bodies. LS1 style throttle bodies will require the use of an adapter to prevent a vacuum leak, except for elbow #3849
which will not work with LS1 style throttle bodies. These elbows are not intended for use on vehicles that need to meet emission compliance standards,
and do not have provisions for EGR or any other vapor recovery system.
BEFORE BEGINNING: Due to the wide variety of engine and chassis designs, it is impossible to provide any significant guidance on vehicle specific
clearances. Many combinations will require modifying or replacing the stock hood. Always verfiy clearances before attempting to fully shut the hood
or damage may occur. The rounded elbows #3847, #3848 & #3849 have been dual drilled to allow them to be mounted in any direction, but the box
style elbows are restricted to a longitudinal mount with #3850 or a lateral mount with #3851.
SPACERS: Engine components such as distributors, fuel rails and thermostat housings can interfere with throttle body and elbow mounting. Some
applications will require the use of spacers to achieve proper clearance. It is recommended that all other engine components be installed before test
fitting your elbow, thottle body, and air inlet system to determine the necessity of spacers with your application. Standard open spacers should be
used to minimze air restriction, such as Edelbrock #8724 (1/2”), #8719 (3/4”), #8720 (1”) or #8712 (2”).
THROTTLE BODY FLANGE BOLT PATTERNS: The throttle body flange of these elbows have been drilled to accept several different bolt patterns. Ford
5.0L style throttle bodies should bolt directly to all elbows without any modifications or adapters necessary. OEM and some aftermarket LS2 throttle
bodies will need to have the lower bolt holes elongated prior to installation. LS1 style throttle bodies will require adapter plate #2737 to prevent a
vacuum leak when used with elbows #3848, #3850 & #3851. Elbow #3847 includes this adapter plate, while elbow #3849 is not compatible with
LS1 style throttle bodies due its 95mm bore.
THROTTLE BODY SELECTION: Edelbrock recommends using the largest throttle body available that is compatible with your EFI management system.
Peak performance can be achieved on most applications with the use of Edelbrock 90mm LS series Throttle Body #3869 (or #38693 for black powder
coat). These throttle bodies have provisions for early style cruise control as well as automatic transmission kickdown. They include a GM 4-wire IAC
and 3-wire round plug TPS.
INSTALLATION: Most installations can be accomplished with hand wrenches or sockets.
Edelbrock Corporation • 2700 California St. • Torrance, CA 90503
Tech-Line: 1-800-416-8628 • E-Mail: Edelbrock@Edelbrock.com
Part #
Length
Bore Centerline
Overall Height
Throttle Body
Flange Angle
Throttle Body Flange
Bolt Pattern
3847
9.0”
.56”
3.62”
102°
LS1, LS2
2
, Ford
3848
7.0”
2.0”
5.04”
95°
LS1
1
, LS2
2
, Ford
3849
5.5”
4.5”
7.00”
90°
LS2
2
, Ford
3850
10.0”
1.75”
4.76”
98°
LS1
1
, LS2
2
, Ford
3851
10.0”
1.75”
4.76”
98°
LS1
1
, LS2
2
, Ford
ELBOW DIMENSIONS
(#3849 shown)
1
Requires adapter #2737 (sold seperately)
2
Edelbrock LS2; OEM thottle bodies will require bolt hole elongation