PROFORM 67165 Billet Metering Block Kit
Product Information
Specifications:
- Product Name: 67165 Billet Metering Block Kit
- Manufacturer: ProformParts.com
- Caution: Avoid drastic changes to emulsion size or power valve channel restriction
Product Usage Instructions
Cautionary Note:
It is crucial to avoid making drastic changes to the emulsion size or power valve channel restriction, as this can significantly impact the air/fuel ratio and potentially lead to engine damage.
Consultation:
When experimenting with emulsion and wide-open throttle calibration, it is highly recommended to seek guidance from carburetor modification books or other reliable resources.
Additionally, consider using devices that monitor the air/fuel ratio across the RPM range.
Installation Steps:
- Ensure the engine is turned off and cool before beginning the installation process.
- Carefully remove the existing metering block following the manufacturer’s guidelines.
- Install the new 67165 Billet Metering Block Kit in place of the old block, ensuring a secure fit.
- Double-check all connections and fittings to guarantee proper installation.
- Start the engine and monitor for any unusual sounds or behaviors.
Features
- Fits 650-1050 CFM 4150 Style Carburetors
- Includes Primary & Secondary Blocks & Gaskets
- High-Quality Billet Aluminum
- Black Anodized Finish
- PROFORM Parts Brand Product
- Sold as One Kit
INSTALLATION INSTRUCTIONS
67165 Billet Metering Block Kit
Fits Holley® Double Pumper®, PROFORM ®, and Quick Fuel Technology ® Carburetors 650 thru 1050 CFM with 4-Corner Idle
Congratulations on purchasing a PROFORM® billet metering block kit for 650 thru 1050 CFM carburetors with a four-comer idle system.
Installation is the same procedure as replacing a conventional metering block. You should become familiar with some features and tuning aspects of this metering block. At the top of the straight “V’ is the idle feed restriction. This screw-in restriction controls the fuel side of the idle and oL-idle air/fuel mixture. Your metering block comes with .033″ idle feed restrictions (the number 33 is stamped on the head).
One additional feature is the 55 power valve channel restrictions, which are also adjustable. These restrictions determine the amount of fuel enrichment the power valve circuit provides at wide-open throttle or when the engine load is sufficient to reduce the manifold vacuum below the power valve’s rated value. The amount or percentage is proportional to the jet size and should not be altered except in special or extreme use cases.
The emulsion holes and the four threaded holes in each vertical slot do not intentionally have any restrictions. The emulsion holes are calibrated (0.028”) and drilled into the bottom of the well. These pre-calibrated emulsion holes have improved performance over your original metering block and are adequate for most applications.
If you wish to adjust the emulsion feature, it is possible to do so by drilling the bottom of all eight wells to approximately 0.050″ or 3/64”. Remove the main jets and power valve before drilling. Be careful only to drill deep enough to break into the main well. After you have successfully drilled all eight holes (four per side):
- Spray quality carburetor cleaner into the top angle channel (booster discharge port) to dislodge any metal shavings from the drilling process.
- Blow out the main well again from the top (booster discharge opening) down using compressed air.
CAUTION: Do not make drastic changes to the emulsion size or power valve channel restriction, as you can significantly alter the air/fuel ratio and could cause engine damage.
When experimenting with emulsion and/or wide-open throttle calibration, it is highly recommended that you consult one of the many books and resources available on carburetor modification. You should also use one or more devices that monitor the air/fuel ratio throughout the operating RPM range.
PROFORM is a registered trademark of Specialty Auto Parts USA, Inc. Holley® and Double Pumper® are registered trademarks of Holley Performance Products, Inc. No carburetor products sold under the PROFORM® trademark, including such parts as may fit with or replace a Holley® part number application, are designed, made, or endorsed by Holley Performance Products, Inc. or any other carburetor manufacturer.
CONTACT
© 2024 Specialty Auto Parts U.S.A.
Frequently Asked Questions
- Q: Can I make significant changes to the emulsion size?
- A: It is advised not to make drastic changes to the emulsion size, as this can alter the air/fuel ratio and potentially lead to engine damage. Consult resources for guidance.
- Q: How should I monitor the air/fuel ratio during calibration?
- A: Utilize devices designed to monitor the air/fuel ratio throughout the RPM range to ensure proper calibration and performance.
Documents / Resources
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PROFORM 67165 Billet Metering Block Kit [pdf] Installation Guide 67165 Billet Metering Block Kit, 67165, Billet Metering Block Kit, Metering Block Kit, Block Kit |
