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Holley .150in Needle & Seat Assembly 6-521

Part Number: HLY6-521
HOLLEY
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SKU:
HLY6-521
UPC:
90127465738
MPN:
6-521
Condition:
New
Availability:
Ships Same Business Day
Weight:
0.03 LBS
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$49.95
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Description

A precision needle and seat assembly is critical for consistent fuel metering in Holley carburetors—any wear or contamination directly impacts your air-fuel ratio and engine performance. This .150in titanium assembly delivers adjustability and durability, ensuring reliable fuel delivery whether you're tuning on the dyno or competing on the track. If you're rebuilding or upgrading your carburetor, this is the kind of OEM-quality component that separates a properly functioning fuel system from one that leaves power on the table.

  • Holley 6-521 assembly
  • .150in orifice size
  • Titanium construction
  • Adjustable needle and seat
  • Sold individually
  • Carburetor fuel metering
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Specs

MFG Part #:
6-521
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Fitment

Fitment for Holley .150in Needle & Seat Assembly 6-521

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