Have you seen E46 M3 CSL prices lately? They are - unless you already own one - downright depressing. Just one is listed for sale on Autotrader currently, and it’ll set you back £69,990. And that’s not the most expensive I’ve seen: there’s even one for £100,000 knocking around.
If you want a very special E46 M3 but can’t stretch to that, let me present a solution: the M3 you see here. And while it looks like any other E46 M3 from the outside, as you’ll see from the next image, it has something rather special under the bonnet.
Yep, it’s the S85 5.0-litre V10 from an E60 M5. Better yet, it’s been hooked up to the six-speed manual gearbox from an E9x M3.
We’re looking at the M5’s 500bhp output in a car that weighs around 300kg less. This, ladies and gents, is going to be a very quick car. And it shouldn’t be quite as nose-heavy as you’d imagine: despite displacing an extra 1800cc, the S85 V10 weighs just 25kg more than the stock M3’s S54 straight-six.
The price for all this? £30,000, which - when you consider the amount of work that conversion will have required - doesn’t seem so bad.
Can you think of a better BMW engine swap than this? Let us know in the comments!