NC MX-5 2.5L Swap Info

NC MX-5 2.5L Swap Info

There is a lot of information floating around about the 2.5L swap online, but the specifics can vary greatly depending on where you read about it. We wanted to put together some verified information to help demystify the process. Overall, this swap is very straight forward as far as motor swaps go. The engine looks nearly identical when installed, and uses the OEM ECU (with a tune), motor mounts, and wiring harness.



2.5 Swap Parts List:

Engine: 2.5L Ford Fusion Via LKQ@eBAY (Tip: LKQ will ship to Advanced Auto for free in most cases, but you will need to call them when you’ve picked your engine)


Required Parts, Tools, and Fluids:

  • Serpentine belt: Dayco 5060910 / 6PK2310
  • Pilot Bearing: YF09-11-303
  • 1 x Crankshaft bolt: LF01-11-406
  • 2 X Crankshaft diamond washer: L3H5-11-407
  • 2 X Camshaft bolts: LF17-12-428
  • 2 X Camshaft Diamond Washers: L3K9-12-429
  • VVT SOLENOID PIGTAIL: Comes on 2.5 wiring harness (If missing, use part number Motocraft WPT1251)
  • MZR Counter Balancer Delete Plug: Search eBay for "MZR Balance Shaft Delete" (If using Massive parts, may be under part number MAEN'8647)
  • OEM oil pick-up tube: (LFE2-14-240A)  along with the O-ring (L309-14-248).*(only needs to be replaced if your old motor is damaged/spun a bearing, as it will be full of metal in that case)
  • Coolant - FL-22 or equivalent - 2 Gallons
  • MZR Timing Tools: Ebay search for "MZR Timing tools" should look like a bar and a pin with some threads on it (massive makes a kit under part number MATO'8754)


Optional but Recommended Gaskets:

  • Exhaust Gasket: L32713460B
  • Throttle body gasket: LFE213665
  • Intake Plenum gasket: LFE213135
  • Water outlet gasket: LFE215169
  • EGR Gasket: LF0120305
  • OIL Filter gasket: LF0214342


Parts Re-used from 2.0:

  • Oil pan
  • Oil filter mount
  • Valve cover
  • Crank pulley
  • Fuel rail (use 2.5 injectors in 2.0 fuel rail)
  • Intake manifold
  • Pulleys & tensioner
  • Accessories
  • Intake manifold runner (should be ported to match 2.5L head)


Recommended but not Required Parts:

  • Timing cover from a Mazda 2.5 (this cover has provisions to access the timing chain tensioner lock, the ford cover does not. Only required if there is ANY chance of you wanting to do cams later)
  • Ford Ranger Oil separator plate (Has clearance for intake manifold in RWD): 4L5Z-6A785-AA
  • 1.8" Primary header - The engine will run fine with other smaller aftermarket headers, but it will be very difficult to install this header with the engine in the car. Much better off installing while engine is out of the car.


How to Convert 2.0L to 2.5L:

  • Remove oil pan, valve cover, intake manifold, and any other external accessories or attachments from 2.5L motor
  • Remove sensor between cylinder 2 and 3 on 2.5L motor
  • Transfer VVT solenoid gasket from 2.5L valve cover to 2.0L valve cover
  • Install balance shaft delete plug
  • Cut notch on timing cover to clear belt routing to power steering pump (note, this will not be needed if you use a Mazda timing cover, only ford will need to be modified)

  • Port match 2.0L intake manifold runners to 2.5L, use RTV to seal to head
  • Transfer 2.0L components to 2.5L motor (motor mounts, pulleys, sensors, wiring harness, etc)
  • Swap the appropriate VVT solenoid connector on harness
  • Transfer crank pulley, replacing the diamond washers
  • Install clutch/flywheel


How to Remove From the Top:

  • Recover AC system (optional but can make life easier)
  • Drain engine oil and coolant
  • Remove hood, battery & box, air box, and ECU & mount
  • Remove plastic cowl covers and metal cowl cover brace
  • Disconnect PS pump and move aside
  • Disconnect AC compressor from motor (if system wasn’t drained)
  • Remove header & midpipe
  • Remove transmission
  • Remove motor
  • Prepare 2.5L motor for installation (see above)
  • Reassemble everything
  • Refill coolant
  • Refill AC system (replace the drier)
  • Tune ECU


How to Remove From the Bottom:

  • Recover AC system
  • Drain engine oil and coolant
  • Remove midpipe & disconnect driveshaft from diff
  • Support transmission
  • Remove PPF
  • Remove shock tower nuts on front struts
  • Disconnect PS pump
  • Disconnect flexible clutch line
  • Remove lower radiator supports
  • Disconnect steering column
  • Drain power steering fluid
  • Disconnect upper and lower radiator hoses
  • Support subframe
  • Carefully remove the nuts and bolts that hold the subframe and underside brace
  • Carefully lower assembly away from body (or raise body if on lift)
  • Prepare 2.5L motor for installation (see above)
  • Reassemble everything
  • Refill coolant and power steering fluid
  • Refill AC system (replace the drier)
  • Bleed clutch line
  • Tune ECU


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