Alpina B5 GT 2023 review

Beginning in 1976 with the ultra-rare B2, Alpina has been making its mark on the BMW 5-series for almost half a century. The limited-run (250 worldwide) G30 B5 GT (G31 Touring) is Alpina’s most potent take to date, with more power than any model in its catalogue. Not only does it have the numbers, it’s also the final 5-series ever to be produced by Alpina in its current form, with no plans for a successor in the pipeline.

Under its new M5-derived bonnet is BMW’s 4.4-litre twin-turbocharged N63 V8, lifted from the ordinary 550i. This unit is far from standard, though, with Alpina making numerous changes in order to achieve that headline 625bhp figure. In addition to the B5’s uprated cooling system, pistons, turbochargers and transmission, the GT is equipped with a less restrictive, flow-optimised intake, modified exhaust centre section and an ECU tweak. The result is a 13bhp uplift over the standard B5, bringing output to within just a single bhp of the hardcore M5 CS – torque stands at a potent 627lb ft between 3500 and 5000rpm, 74lb ft more than the CS.

> BMW M5 Competition F90 review – verdict, specs and prices

Sent to all four wheels through a modified eight-speed ZF torque converter automatic, performance is predictably strong. The 0-62mph sprint is said to come in 3.2sec (3.4sec for the Touring), with 124mph coming at an impressive 10.2sec and 10.9sec – for reference, the Ferrari 458 Italia manages the same in 10.4. Top speed is also of key importance, with its power uplift and subtle aerodynamic tweaks allowing for a 205mph peak speed in saloon form.

Heading out onto Zandvoort circuit, the B5 GT immediately feels every bit of its 625bhp, with that high torque figure providing relentless in-gear pull. A ZF torque converter will never be as sharp as a dual-clutch, but updates to the transmission do make it snappier than others we’ve tried, without the frustrating artificial kick that some have begun to utilise. While unlikely to be an issue for most Alpina drivers, auto-upshift at the red line is something I could do without.

20

Luxury and refinement are a higher priority than track focus, and so weight isn’t low. The saloon tips the scales at 1980kg, with the Touring 100kg heavier still. Pair these numbers with its output and you get a 321bhp/ton (305bhp/ton Touring) power-to-weight ratio, more than adequate for its typical use case, but no match for the 349bhp/ton figure of the lighter M5 CS.

Sweeping, high-speed sections prove just how capable the B5 GT can be, with its tweaked chassis set-up inspiring confidence with neutral mid-corner balance – certain sections are far from perfectly paved, and yet the GT deals with these tricky mid-corner upsets without an issue. Though unlikely to withstand multiple back-to-back track sessions, braking performance also remained consistently strong – initial bite and feel is lacking, but this is a luxury GT, after all.

While chassis hardware is similar to that of the standard B5, a lowered ride height gave Alpina the opportunity to tweak geometry further. The saloon features traditional springs on all four corners, while the Touring utilises air springs at the rear, with active anti-roll bars carried across from the B5. While its additional weight is apparent under acceleration, the Touring holds up well, with its dynamic ability virtually indistinguishable from that of the saloon.

20

A UK road drive would be the true test of real-world ride quality, but our brief experience on some not-so-perfect surfaces suggest that it would fare well – 35- and 30-profile front and rear tyres could be a sticking point, though. Spring rate feels higher than on the likes of the B8, but quality damping and those active anti-roll bars make overall ride quality as refined as you’d hope. While impressively transparent when pushing on, rear-wheel steering also provides more control and useability in the real world.

The B5 GT’s all-wheel-drive system feels refreshingly rear-biased, allowing for some play on the edge. Adopting the standard B5’s steering map, there’s not much in the way of off-centre precision, but add some lock, load the chassis, and it becomes plenty responsive for a spirited drive.

Despite its swansong status, the B5 GT retains the marque’s trademark understated design. A set of new 20-inch, 20-spoke wheels finished in Satin Bronze are the most notable change, with subtle front canards, the M5’s ridged bonnet and decals also part of the package. There are further tweaks inside, with an Alpina-themed digital dash, open-pore wood trim and bespoke aluminium shift paddles making an appearance – buyers can also opt for more supportive seats from the BMW XM, tweaked in design for the Alpina.

20

Price and rivals

Priced from €145,500 (c£124,324), it’s far from cheap. The likes of the Audi RS6 and Mercedes-AMG E63 S will set you back well in excess of £100,000, but step up the luxury and the equivalent Porsche Panamera or Bentley Continental GT will cost you more. The upcoming BMW M5 Touring would give the estate some strong competition, but with plug-in hybrid tech and a more focused brief, it’s unlikely to offer the same charming qualities. Regardless of whether you feel its price is justified, the B5 GT offers a unique package we’re unlikely to see again. And besides, the market has already spoken; every example is already accounted for.

Alpina B5 GT specs