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ECU & Harnesses

ECU & Harnesses are the brains and wiring backbone of any EFI conversion. Whether standalone or piggyback, these units offer full control over fuel mapping, sensor inputs, and injector timing—vital for tuning modern engines.

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Holley Dominator EFI Auxiliary Harness (HO558-403) HO558-403
$424.00 - $424.00
$424.00
$424.00 - $424.00
$424.00
+ GST

Holley Dominator EFI Auxiliary Harness (HO558-403)

J3 ECU Connector

DOMINATOR EFI J3 P3 AUXILIARYJ3 ECU ConnectorPart Number: HO558-403 17 User Programmable Inputs and Outputs

$424.00 - $424.00
$424.00
$424.00 - $424.00
$424.00
+ GST
Holley Terminator X Max ECU Kit, 92-97 4R70W Transmission - EV1 Injectors (HO550-943)
$4,233.50 - $4,233.50
$4,233.50
$4,233.50 - $4,233.50
$4,233.50
+ GST

Holley Terminator X Max ECU Kit, 92-97 4R70W Transmission - EV1 Injectors (HO550-943)

Suit Ford MPFI

TERMINATOR X MAX ECU KITSuit Ford MPFIPart Number: HO550-943 Take control of your conventional Ford engine with Terminator X! Don't settle fora fa...

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$4,233.50 - $4,233.50
$4,233.50
$4,233.50 - $4,233.50
$4,233.50
+ GST
Holley GPS Digital Dash USB Module (HO554-140)
Holley GPS Digital Dash USB Module (HO554-140) HO554-140
$227.80 - $227.80
$227.80
$227.80 - $227.80
$227.80
+ GST

Holley GPS Digital Dash USB Module (HO554-140)

Suit HO553-109 & HO553-106 Digital Dash

GPS DIGITAL DASH USB MODULESuit HO553-109 & HO553-106 Digital DashPart Number: HO554-140 Have you been searching fora reason to discard your o...

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$227.80 - $227.80
$227.80
$227.80 - $227.80
$227.80
+ GST
Holley EFI 12.3" Pro Dash (HO553-111)
Holley EFI 12.3" Pro Dash (HO553-111) HO553-111
$5,445.60 - $5,445.60
$5,445.60
$5,445.60 - $5,445.60
$5,445.60
+ GST

Holley EFI 12.3" Pro Dash (HO553-111)

Digital Touch Screen

HOLLEY EFI 12.3" PRO DASHDigital Touch ScreenPart Number: HO553-111 Trust. Whether it's your engine builder, team members, or EFI System, trust is...

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$5,445.60 - $5,445.60
$5,445.60
$5,445.60 - $5,445.60
$5,445.60
+ GST