FEB 02nd 2016

Dan Trent – Why A Boring Looking 3‑Series Saloon Is The True M3 Successor

Dan Trent

Exposure to a Performance Car review of the Lamborghini Countach 5000QV at an impressionable age set Dan Trent on course for a life-long obsession with cars. As editor of PistonHeads.com he’s got direct access to a classifieds repository of over 100,000 such vehicles to browse day in, day out. Temptation is never far away. He’s still some way off that Countach though. Dan Trent on Twitter


Here’s a test of your commitment to geekery. Would you be prepared to invest in a four-door BMW 3-Series saloon all but indistinguishable from a rep special M Sport 320d? Is homologation provenance something you can put before actual on-road performance? And how tolerant will your friends and family be when you have to explain, yet again, ‘yes, I know it only has 170bhp but it’s got a carbon-fibre engine cover and the cylinder head was cast in an F1 engine plant!’

Bill WIsdom promo 74mm

The BMW 320si is one of those homologation obscurities dealers probably hated with a passion when they arrived in showrooms but, for motorsport geeks, needs to be properly celebrated. Because this, more than any other car to wear the badge since, is the true spiritual successor to the all-conquering, much celebrated and now hugely expensive E30 M3. Indeed, if you wanted evidence M now stands more for marketing and not motorsport, the fact this car was tucked away at the unfashionable end of the product range and not badged M3 is the smoking gun you need.

Announced in 2006, 500 of the 2,600 production run of 320si saloons were brought to the UK. Built to homologate the 320i for the WTCC, the 320si road car celebrated Andy Priaulx’s final round victory in the 2005 series that sealed both driver and manufacturer titles. You need to be a proper spotter to clock the Motorsport wheels and satin chrome mirror trims, the car otherwise identical to civilian M Sport E90 3-Series saloons. But when you know what you’re looking at the significance makes all the difference.

BMW 320si

And the engine is a geek’s delight. Under that carbon cylinder head cover – contributing to a 10kg weight saving – is a proper homologation motor with a cylinder block cast alongside BMW’s F1 engines and assembled at Ham’s Hall near Coventry. For race revs BMW engineers binned the standard 320i’s Valvetronic induction system and made the engine slightly more oversquare, increasing bore by 1mm and reducing stroke by 2mm. Compression was increased from 10.5:1 to 11:1. Proper old-school tuning in other words.

The result? Ah, that’s where it gets a little trickier to maintain the enthusiasm: 170bhp at 7,000rpm and a 7,300rpm redline say much about the engine’s character. Likewise the meagre 147lb ft at 4,250rpm. 0-62mph in 8.1 seconds and a top speed of 140mph are, in isolation, OK. But unless you absolutely thrashed the hell out of it you likely wouldn’t see which way that identical looking 320d went, let alone contemporary hot hatches. Hand on heart, it’s not actually that fast.

BMW 320si

Am I bloody-minded enough to want one for all that? Absolutely I am. Because there is, and always has been, something rather enticing about homologation specials, especially ones with a winning pedigree. The ‘real’ M cars make a lot of noise about their supposed motorsport breeding. But if unsung heroes like the 320si didn’t exist to help stars like Priaulx bring home the silverware it’d all be meaningless posturing. Indeed, the year this car was launched also saw Priaulx seal his third consecutive WTCC title in the 320si by just a single point over his team-mate Jörg Muller. And without this car he couldn’t have done it. For its role in powering a British driver to such success it’s a car worthy of celebration. And I’d love one.

Share this