Frankenstein Motorworks

How to swap a 2AR-FE into your Toyota MR2 Spyder

This guide will grow over time, if you have any questions please do not hesitate to contact me:

Another great place to get quick answers is, and

Why the AR Family of engines

The modern Toyota engines really are quite amazing. At first I'm starting with the 2AR-FE (2.5L 4 cyl, rated at 180hp) This engine is the cheapest in this family to purchase because it's been available for the longest. With a solid intake and exhaust it tends to make about 205hp to the ground. From here supporting other engines in the AR family will simply require different right side motor mounts and potentially different headers. I look forward to adding support for the 8AR-FE as soon as the 2AR stuff is done. This engine uses direct injection and a turbo to produce 265hp stock. I'll update this with an actual dyno'd number once i've performed the swap.

Contents of this guide

This guide will have five major sections covering how to install the 2ar-fe motor into the MR2 Spyder. Each section will comprise of a video and a text description.

  1. Drivetrain Preparation

  2. Electrical (wire harness work)

  3. Chassis Preparation & Drivetrain Install

  4. Plumbing (air, fuel, coolant and vacuum)

  5. Interior and Electrical (installation)

Drivetrain Preparation

Drivetrain preparation is everything that can be done to the motor and transmission before the MR2 has to be taken out of commission. Doing this ahead minimizes the downtime for the car. You can see the Video for this section here.

  1. make the two axles using the three rav4 axles according to the document here.

  2. install the new crossgate detent cam inside the transmission according to the document here.

  3. install clutch and flywheel of choice (scion TC application, lightweight flywheels available as well as high horsepower clutches if desired)

  4. mate motor and trans together

  5. install new spark plugs

  6. install all four motor mounts on drivetrain.

  7. install A/C delete idler and shortened belt (or plan on modifying the frame rail to fit the stock A/C compressor. the custom A/C setup does not exist yet)

  8. remove DBW throttle body and remove mesh covering 40% of intake opening and reinstall DBW throttle body

  9. install thermostat housing

  10. install header

  11. *make* dip stick tube to reach around to front of engine (this is in the queue to make but is unlikely to be ready by your first install. I just used the stock spyder dip stick and made a custom tube)

Electrical (wire harness work)

This is yet more work that can be done before the MR2 is taken out of commission but it seemed more appropriate to split it in its own video. Video is available here: {video not done being edited yet, should be available late June 2019}

  1. Modify engine harness according to instructions in here. (note, no link right now because document is being updated)

  2. Install body controller circuit board in stock ECU case.

Chassis Preparation & Drivetrain Install

{work in progress}

Plumbing (air, fuel, coolant and vacuum)

{work in progress}

Interior and Electrical (installation)

{work in progress}

This will be filled out in the coming weeks but feel free to reach out if you need answers quicker: