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Holley Inc.

Holley Inc. (NYSE: HLLY); operating company Holley Performance Products, Inc.
Founded 1903 (per Holley 10-K; Wikipedia traces the Holley brothers' first company to 1896)Nashville, Tennessee, USA (principal executive offices); main owned facility in Bowling Green, KentuckyFounders: George Holley and Earl Holley

Holley is a US performance-aftermarket group, founded in 1903 and famous for carburettors, that now owns many brands including Holley EFI, Sniper EFI, MSD and AEM. Its EFI line (Dominator, HP, Terminator X, Sniper) runs Holley EFI PC software and touchscreen handhelds and is aimed mainly at US V8 and domestic platforms.

See 4 Holley ECUs ↓Find a Holley EFI tunerWebsite ↗Software downloads ↗Contact page ↗

History

  1. 1903Holley founded (10-K); brothers George and Earl Holley began building vehicles in Bradford, PA, in 1896 (Wikipedia)
  2. 1905Holley Brothers Company established in Detroit, concentrating on carburettors (Wikipedia)
  3. 1952Plant moved from Portland, Michigan, to Bowling Green, Kentucky (Wikipedia)
  4. 1968Acquired by Colt Industries (Wikipedia)
  5. 1998Sold by Coltec Industries to a management team backed by Kohlberg & Co. (Wikipedia)
  6. 2015Acquired MSD Group (MSD, Mr. Gasket, Accel and others) (Wikipedia)
  7. 2018Holley EFI V5 software released (Active Speed Management, Staging Assist)
  8. 2021Acquired substantially all assets of AEM Performance Electronics (15 Apr 2021)
  9. 2021Business combination with SPAC Empower Ltd. completed 16 July 2021; listed on NYSE as HLLY

Contact

Address
1A Burton Hills Blvd, Suite 240, Nashville, TN 37215, USA (principal executive offices per 10-K)
Phone
(270) 782-2900
Email
Not published
Website
www.holley.com
Contact
Contact page ↗

Tuning software

Current
Holley EFI V6 software, Build 400 (covers ECU, dash and handheld firmware); Sniper EFI software v1.3 Build 50
Cost
Free downloads from Holley's tech library
Download
Official download page ↗
Old versions
Official archive ↗

Software history

  1. 2018Holley EFI V5 · Announced Sep 2018; complete file set Build 171 still offered
  2. –Holley EFI V4 · Still offered: V4.0 Build 110 plus older Builds 30 and 32; release year not found
  3. –Holley EFI V6 · Current, Build 400; release year not confirmed
  4. 2026Sniper EFI software · v1.3 Build 50 (Windows); Terminator X uses Holley EFI software (no separate download listed)

Links go to the maker's own download pages. Installers are not hosted here.

Holley ECUs

4 current. Cheapest first.

Pixel illustration of the Holley HP EFI ECU (554-113)
Holley
MidWire-in

HP EFI ECU (554-113)

US$2,100
16INJ
8IGN
0DBW
1λ WB
8MAX CYL
2KNOCK
1CAN
✓LOG
FlexTractionLaunchBoostGearboxEthernet

Latest Holley news

All ECU news

22Jan 2026
Company

Holley renames Domestic Muscle vertical to American Performance

3Dec 2025
Show

Holley previews 2026 at PRI Show with Terminator X Bluetooth EFI kits

7Nov 2025
Show

Holley Terminator X Bluetooth module recognised at SEMA 2025

4Nov 2025
Show

AutoMeter debuts EFI CAN Bridge for Holley EFI at SEMA 2025

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