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Moroso 65425 Holley Vacuum Secondary Spring Kit

Manufacturer

Picture for manufacturer Moroso

Part Number

65425
7 reviews
Sale Price

$18.13

In Stock (10+)

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Usually delivered within 2 days

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No Hassle Returns

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Live-in-stock inventory

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Fitment guaranteed

Fitment guaranteed

Product Details

The Moroso 65425 Vacuum Secondary Spring Kit is designed to fine-tune Holley carburetors with an effect on initial operating and full upper rpm performance. This kit contains a variety of secondary diaphragm springs to tailor the secondary opening characteristics to a particular engine.

Key Features:

  • Includes seven color-coded springs ranging from light to heavy tension
  • Allows precise tuning of vacuum secondary opening rate and timing
  • Color-coded springs for easy identification and selection
  • Complete instructions included for proper installation
  • Compatible with Holley 4150, 4160, and other vacuum secondary carburetors

The springs regulate the opening point and rate on vacuum secondary Holley carburetors based on venturi air velocity. By selecting the appropriate spring tension, you can customize when and how quickly the secondary throttle plates open, optimizing engine performance across different RPM ranges and load conditions. This tuning capability helps eliminate bog or hesitation while maximizing throttle response and power delivery.

This company is pretty good even when I found what I was looking for cheaper then some other websites

This is my second time ordering from Autoplicity and both times they had the lowest price on the items I was looking for (brake pads and CAI filter). Fast shipping, my filter was at my door two days later. Overall very satified.

Once I've ordered from autoplicity and the part was wrong. I'm giving them another chance and the check out was much easier. Things were updated and now it's smoother so hopefully everything will go well this time

Great products, and pricing

I was amazed to find the air intake I wanted at the price offered by Autoplicity. No one else came close and the item was shipped very quickly. This store has been added to my favorites list........Thank You!!!!

Order was fast, had the products I wanted in stock, and vehry pleased. Thank you 5 star service.

I received my Corsa exhaust for my Sequoia today; I had issues with Autoplicity with regard to the order/availability which once brought to their attention was rectified; in the end I had to wait a little longer than expected to receive my order but it was resolved and hopefully the management learned something from this experience.

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