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Air and Fuel› Fuel Injection Systems and Components - Electronic
Holley
HOLLEY MA MPFI W/TRANS CONTROL 550-917-B
SKU: H00E 550-917-B
Moderate — 2–4 hours
Overview
This system includes 4 programmable inputs and 4 programmable outputs for accessories like electric fans and boost solenoids. It comes with base maps for common LS engine combinations and a 3.5-inch touchscreen handheld for calibration, tuning, and gauge display. Free EFI tuning software is also provided for advanced users.
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Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.
Fitment
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Specifications
| Brand | Holley |
| Part Number | H00E 550-917-B |
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Returns & Fitment
Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.
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