Stock BMW E46 M3 Vs Modified: How Much Difference Can A Few Parts Make?

Anyone who spends a lot of time on the Car Throttle app will be aware of the BMW obsession within the staff here. We have Gabor and his E46 330Ci, Alex and his E36 M3, and John and Adnan with their E46 M3s. Now, as the resident JDM guy, I’ve never really prescribed to the M3 fanboyism, but I’m open-minded and happy to discover new things to enjoy, so I decided to take it upon myself to write a completely unbiased review of arguably the pinnacle of M3 fanboyism, the E46.

Fortunately, the two E46 M3s I had available to me were at very different ends of the scale. John has modified his M3, with an HSD coilover suspension upgrade offering 16-way adjustable dampers and full control over ride height, a K&N air filter, a Superchips engine remap offering an extra 20bhp, and slightly wider rubber. Importantly, it is also SMG ‘boxed.

Adnan’s on the other hand could not be further from all that, as it is a completely stock, manual M3, with nothing more than a set of tints. And a Car Throttle sticker (+50bhp). So, it’s time to get comparing, and there really is only one place to start…

Gearbox

There’s been a lot of hate for BMW’s Sequential Manual Gearbox, more commonly referred to as SMG. It’s essentially an automatic gearbox, with the car automatically operating the clutch and changing gear when you want it to. Unfortunately it’s absolutely terrible at doing this, to the point where it’s actually preferable to keep the car in manual mode at all times, even when cruising around town. This becomes incredibly tiresome, but the alternative is a horribly lurching shift, and a car that never knows what gear to be in.

It starts to make more sense when you start pressing on. Keep it in manual mode and up the severity of the shifts to the point where it feels like you’re getting punched in the back every time you flick a wheel-mounted paddle and everything begins to fall into place. Shifts are incredibly quick, and suddenly come with the drama all that other modified work deserves - I’m not sure it’d be quite as much fun in a standard car, but I suspect either way the SMG is at its best when you’re pushing hard.

The manual on the other hand doesn’t really have an upside. The throw is quite long, the shift is fairly vague, and it’s anything but satisfying. Around town it’s much nicer than the SMG, offering a more relaxed alternative, however that’s not what you buy an M3 to do. When you’re pushing hard you’re not given 100 per cent faith that slamming a gear home will actually work, so you take that extra split second to make sure you’ve landed the cog home. It takes you out of the moment just long enough to be disappointing.

Honestly? The gearbox is the most disappointing aspect of the BMW E46 M3. I didn’t really like either the manual or SMG options, but I would say that if you’re intending to drive this car hard - and you should - take the SMG and forgive its foibles at slow speeds.

Engine

When I drove the new F80 M3, I was startled by just how violent the torque delivery was. On anything but bone dry roads you could never really just get up and go, and according to enthusiasts it’s like that because all M3s are hardcore. So when I started pressing on in Adnan’s stock M3 I was expecting some of the aggression I saw in John’s car to be there from stock.

To my surprise it was actually rather mild-mannered, offering 3-series levels of comfort and quietness until you started to give it what for. Treat the M3 like it wants to be treated and you unlock a different character, though; revving the engine out to the red line to make that raspy exhaust note take over seems to wake the chassis up and make it more alert. It loves to be revved, this engine, and is silky smooth all the way to the limiter.

John’s M3 has had a power hike, so it’s naturally more alert. Interestingly, its character is pretty similar to the stock engine’s, just turned up to 11. The power’s more readily available, but revving it out is still the name of the game and the best way to give you the fizz. I may not like the sound of the straight-six, but I can’t deny it feels good under your right foot.

Handling

When you look at the modifications made to John’s ride, you’ll be unsurprised to learn that handling is where the biggest chasm between these cars’ abilities lies. The Laguna Seca blue M3 is slammed to the ground, giving it the kind of ‘because racecar’ wide stance befitting a car geared towards track use. Fortunately it’s not all show and no go, as these upgrades transform the way the car gets about at speed.

In the stock M3, I was a little surprised that it felt rather wafty. The capabilities to carry speed are definitively there, but you feel a little like you’re floating across the surface rather than biting into it, which saps a little confidence, particularly when driving your boss’s car. The ride is brilliant, however, ensuring that even the most winter-abused B-roads won’t unsettle it, but this is what takes away some of the initial feedback from the front wheels. It’s a bit of a Catch-22, but I’d prefer a firmer ride in exchange for the feedback.

A firmer ride is certainly what you get in the modified M3. I’m all about lightweight, stripped-back sports cars, so I’m perhaps more impervious to a firm ride than most, but I feel like the rough and jiggly low speed ride is a more than acceptable trade off for the unbelievable ten-tenths performance.

When you’re driving John’s car hard it comes alive and all of those upgrades begin working together to make sense. Every bump that bugged you in traffic earlier, and that horrendously laboured automatic shift in the supermarket car park the previous night are completely forgotten. The dampers are fantastic, soaking up imperfections and yumps in the road better than any car slammed this low ever deserves to. The feedback from the front wheels is instant, with your whole body soaking up the sensation of grip on the outer wheel. I’m sold.

Conclusion

Despite how it probably sounds, I do quite like the BMW E46 M3 in stock form. It’s not the most thrilling thing to drive, but it’d make a brilliantly capable daily driver. The modified example takes the needle too far the other way for my liking. With a decent gearbox I could probably accept it as a daily, but I could only ever have the car in its current form as a weekend warrior.

For me the sweet spot would be somewhere between the two, with the suspension setup from John’s car and some decent rubber you’d have all the grip you could ever desire. I just don’t think I could ever get over the gearbox situation…