The Speed Academy team digs back into a BMW project that had been on the sidelines — until now.


Speed Academy is a website and YouTube channel based on making things go fast and enjoying cars. Peter Tarach and Dave Pratte are the forces behind Speed Academy.

The TTAC Creators Series tells stories and amplifies creators from all corners of the car world, including culture, dealerships, collections, modified builds and more.

An AI-produced summary of the transcript, edited by a staffer, is below.

[Image: Speed Academy/YouTube Thumbnail]


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Summary


The transcript follows the return of a heavily modified BMW E46 M3 with a Toyota 2JZ-GTE engine, which had been built in 2020 with a track-focused philosophy. After sitting largely untouched for about five years, the goal is now to make the car more refined, comfortable and usable as a street/weekend car rather than simply maximizing track performance. 

The original build vs. the new direction

The car began as a relatively inexpensive, rusty E46 M3 and received a 2JZ engine along with roughly $15,000 in aftermarket parts. While the resulting car was highly capable on a track, several modifications have proven frustrating on the street. The owner particularly dislikes the motorsport-grade shifter, which has extremely short, tight throws and requires considerable effort and concentration in traffic. 

The clutch is similarly aggressive, apparently a Stage 3/six-puck-style unit. It works well for holding power but becomes grabby and chatters as it warms up, making it another poor fit for comfortable street driving. 

The 2JZ remains the star

Despite the flaws, the owner is still extremely enthusiastic about the car. The internally stock 2JZ VVT-i is praised for its smoothness, sound and power delivery, with the owner saying it is even smoother than the original BMW S54 engine. The engine remains one of the primary reasons the car is worth saving and refining. 

There are, however, some mechanical issues to address. A cracked turbo coolant feed line caused a coolant leak after the car was retrieved from storage. The turbo water lines will be rebuilt. There is also a possible exhaust/wastegate leak, although the manifold and turbo system show no obvious soot or cracking. 

The engine also has a noticeable dead spot between roughly 1,500 and 2,000 rpm, which the owner suspects is related to the injectors. Replacing the injectors is planned. 

Brakes and other track-focused hardware

The car's motorsport-oriented brake setup is another source of street-car refinement issues. Its floating two-piece rotors rattle over bumps, producing an undesirable clanking sound. The owner plans to address the setup and potentially convert the system back toward a more conventional configuration. 

The rear suspension and subframe, by contrast, appear to be in good shape. The rear mounting points were reinforced, adjustable arms and JRZ components remain in place, and the owner doesn't anticipate major work in that area. A BimmerWorld rear diffuser and single-exit titanium exhaust remain among the car's distinctive modifications. 

Air intake redesign

One of the more obvious remnants of the original build is a crude-looking intake box that was quickly fabricated for drag racing. Although it worked, the owner now wants something cleaner and more effective.

The plan is to use a 3D-printed custom airbox, potentially designed with help from a friend and produced using a Prusa Core One 3D printer. The project could also establish a capability to design and print custom parts for other cars at the shop. 

Adding air conditioning

Another major change is the addition of air conditioning, considered essential to making the car enjoyable during the summer. A complete aftermarket AC kit has been purchased, but routing the lines around the existing 2JZ turbo hardware may prove challenging. The video promises to document the process of installing custom AC in the 2JZ-swapped BMW. 

Rust and brake-line problems

The five years of inactivity have also exposed problems underneath the car. Although the car has remarkably little oil leakage and the titanium exhaust has held up well, inspection revealed a rusted and leaking brake line.

Testing the brakes confirmed the leak. Unfortunately, replacing the affected line will require dropping the fuel tank, since there isn't enough room to access it otherwise. Because the gearbox will already be removed, the owner plans to tackle the brake lines at the same time and potentially replace additional rusty sections. 

Returning the car closer to OEM

A major theme of the rebuild is moving away from the extreme track-car aesthetic and toward a more OEM-looking street car.

Planned changes include:

    • Replacing the current motorsport-style shifter with an OEM shifter.
    • Installing a replacement gearbox with conventional detents.
    • Replacing the old wheels and tires.
    • Converting or modifying the brake setup to eliminate the rotor rattle.
    • Replacing the damaged carbon-fiber front bumper/lip.
    • Removing the yellow high-beam treatment in favor of OEM-style reflective silver.
    • Replacing the silver interior trim with a darker, blue-tinted/Carbon Schwarz-style finish.
    • Replacing the aftermarket steering wheel with an OEM wheel. 

The existing E90 M3 wheels are appreciated, but the owner says it is time for them to go. The tires are also extremely old, dating from 2019, reinforcing the need for a new wheel-and-tire package. 

Other problems and future plans

The car still has several warning lights, including traction-control and airbag warnings, which the team hopes to resolve through CAN-related work. There's also a malfunctioning door-lock system, with one door responding inconsistently to the locking mechanism. The owner is debating whether the problem is worth pursuing. 

Once the mechanical work is complete, the car will return to the dyno for a fresh tune and a new power measurement after sitting for so long. 

Bottom line

This isn't a rebuild intended to make the 2JZ E46 M3 more extreme. It's essentially a second-generation build philosophy: take a car that was originally optimized for the track and turn it into something the owner can actually enjoy driving on the street.

The 2JZ, turbo system, reinforced chassis and performance hardware remain, but the emphasis is shifting toward OEM-like refinement, reliability, comfort, air conditioning, cleaner appearance and street usability. The upcoming gearbox, brake-line, intake, AC, exterior and interior work represents an attempt to preserve what makes the car special while eliminating the compromises that made it difficult to live with.