Suspension Secrets M3ATER Build – Part 1

It’s ambitious challenge time here at Suspension Secrets. We have decided to take on a new project to see if we can achieve an ambitious goal laid out before us. We regard the BMW E46 M3 to be one of the all time great track machines! With 338BHP, front-engine inline six, rear wheel drive and an achievable 50/50 weight distribution it makes for a very thrilling drive. A good Clubsport spec can put you back by about £20k-£25k depending on spec, and the prices are still climbing.

Therefore, we set ourselves a challenge here at HQ… can we build a BMW E46 330Ci track car to contend with and possibly be faster than an E46 M3 Clubsport spec out on track. And the challenge doesn’t end there, the real challenge is… can we accomplish this mission whilst keeping the cost of the build less than or equal to half the price of a Clubsport spec E46 M3?!

Say hello to our aptly named BMW E46 330Ci track car, M3ATER.

Suspension Secrets M3ater track car build. Turning a humble 330Ci into a trackday weapon!

But firstly, let’s take a look at the car we are using as a base.

The Car

M3ATER uses a pre-facelift E46 BMW 330Ci as a base. This means two doors, six-cylinders, six-gears, three pedals, and two driven wheels. During E46 production, which lasted from 1997 to 2006, the 330Ci was the next highest performance E46 available after the iconic M3. Powered by a three litre inline-six, the 330Ci made 228BHP when new, although it remains to be seen how much power has been lost! Regardless, this is a strong and reliable motor, giving the car a good mix of power and torque which is delivered over a predictable and smooth rev-range.

The design of the E46 3-series is an evolution of what BMW does best. It has a long wheelbase, giving it excellent stability in fast corners, and it also makes the car predictable when the tail steps out during oversteer. It also has excellent weight distribution, which further contributes to the E46’s reputation as a fun and engaging car to drive.

The six-cylinder straight-six used in the 330Ci has a stellar reputation for longevity and reliability even when being used hard, which is perfect for the track-focus of our build.

All of these factors give us – in relation to suspension layout and chassis dynamics – an excellent base to use for building a real track weapon.

The Mission

Our aim with M3ATER is to make our humble 330Ci faster around a circuit than an E46 M3 for half the price.

This mission statement comes with a few caveats, however. We aren’t aiming to beat a stock M3, but instead we hope to match a clubsport-spec (half roll-cage, coilovers, bucket seats, and sticky tyres) M3 around the track.

A clubsport spec E46 M3 with sticky tyres, coilovers, half cage and racing seats. Being faster around a race track with one is the goal of our project.

On top of this, we are going to try and achieve this with only chassis and suspension mods – the engine will remain unmodified.

What does this mean? It means getting M3ATER light, really light.

We weighed a clubsport-spec E46 M3 and it weighed 1408kg and had an unmodified S54 engine putting out 338BHP. This gives the M3 a power to weight ratio of 235bhp/tonne. In order to match anywhere near this, M3ATER needs to weigh somewhere around 1000kg all in, to make it at all competitive.

We aim to do this all whilst staying in our budget of £10000-£12500 which includes the cost of the car and the mods (Albeit the labour won’t be included in these prices as we are building it as though you would be at home!)

What are we working with?

Now, M3ATER didn’t arrive here at Suspension Secrets bone stock. In this section, we’ll explore the pre-existing modifications made to the car.

Existing mods include:

  • Stripped interior, with most of the interior trim removed.
  • Bimarco Grip bucket seats with Sabelt harnesses.
  • Steel door cards to replace the OEM units.
  • Aftermarket steering wheel.
  • Uprated front brake discs and calipers.
  • BMW M3 CSL ABS pump and traction control unit.

We’ve decided to get rid of the seats as they have ‘ears’ or ‘wings’ on them. The rules at the Nurburgring forbid these kinds of seats on public days, as the ‘ears’ obscure a driver’s side-to-side visibility.

The steering wheel that came with the car is not a genuine Sparco steering wheel. These cheap counterfeit steering wheels are incredibly dangerous in the event of an accident, and we recommend being very careful when searching for second hand ones. If you are unsure, it is worth spending the extra money and buying your wheel from a well-known manufacturer to guarantee you are getting a quality item.

We managed to bend our steering wheel without much effort to demonstrate how flimsy fake wheels are.

The Plan

In order to match or beat a clubsport-spec E46 M3, we are going to have to be very thorough in trying to make the car as light as possible, and to compensate for the horsepower disadvantage with very high cornering speeds.

Our first step is to strip the weight from the car both internally and externally. After the interior is entirely stripped, we will install lightweight panels and materials, including carbon fibre body parts and plexiglass windows. 

After this we will install a few choice suspension upgrades, the rear end from a BMW E46 M3, and racing wheels. Finally, we will install a custom exhaust, racing slicks and a comprehensive aero kit, which will include front splitter, canards, flat floor and rear diffuser.

With all of these upgrades in place, we will give the car a full suspension setup to make best use of the tyre and the modifications applied in this process. 

Then it’s off to the track, to see if we can fulfil our mission statement!

Will we do it? That’s anyone’s guess.

We’ll be posting frequent updates as the upgrades arrive, so be sure to visit Suspension Secrets again to see our humble 330Ci become an M3ATER!

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