The last-generation Shelby Mustang GT500 was perhaps the best example of this. On paper it looked like the definitive muscle car, with a 650hp supercharged V8 and a top speed claimed to be north of 200mph. In reality it was a huge, crude lump of a thing - imprecise, harsh, permanently battling for traction, and with barely more chance of reaching that alleged double ton than a Reliant Robin towing a parachute up an Alpine pass.
Which is my way of explaining that I categorically don't think the new GT350 is a good car because it's a tweaked Mustang, more despite the fact it's a tweaked Mustang.
The GT350 is the Ford-developed performance iteration of the new Mustang, not to be confused with the tuned-by-Shelby versions you can also buy. It will be sold in the US and certain other territories, but not Europe. Which, after being lucky enough to drive one around its Michigan homeland, I can report that we should be treating as a serious disappointment.
This is far more than a set of stripes and an ECU turned up to 11. Indeed, Ford seems to have taken to heart most of the criticism levelled at the GT500, and the 350 is a car that's been designed to be driven hard rather than deliver some arbitrary numbers. It's fractionally lighter than the standard Mustang, and considerably faster thanks to an effectively all-new flat-plane V8 engine.
Yes, this shares its block with the 5.0-litre unit in the Mustang GT, but has been given a full organ transplant with the new crankshaft and some trick friction reduction turning it from a slugger into a top end screamer. With a red line set at 8,250rpm this is, by our reckoning, the highest revving engine that's ever been fitted to a production Ford.
There's no doubting how different it is from the moment you fire it up. The regular GT V8 starts with the sort of bubba-bubba idle that's been the soundtrack for American performance since the year dot; the GT350 has a far busier idle note - bababababababa - that makes it sound like it should be sitting in a pit garage. Even with the switchable exhaust left in its standard mode it's loud. Switch to 'Sport' using the steering wheel button and it's already bordering on being anti-social before you've driven anywhere.
Not that the GT350 is an undriveable special. For all its been designed for regular track use (especially the GT350R variant, more on which in due course) it remains happy to do everything you'd expect from a standard Mustang; from trundling down a drive through lane to challenging a Camaro to an impromptu stop light drag race. The clutch pedal feels slightly heavier than the standard GT, and although the 350 has switched to a Tremec six-speed gearbox (which weights slightly less than the standard Getrag) the shift action for the six-speed box feels pretty much identical. The engine is tractable at lower speeds although without much torque. It starts to pull hard around 3,500rpm and from then on it just gets better, and louder.
Indeed there's enough sound and fury going on by around the 6,500rpm mark - where the standard Mustang GT calls time - that you have to resist the urge to change up. You need to - it pulls with increasing vigour all the way to 7,500rpm at which peak power arrives and, while it tails off slightly beyond that, the 8,250rpm limiter will be useful for holding gears longer on track. A nice touch is the repurposing of the dash-mounted LEDs that basic Mustangs use as part of their collision warning system, and which are turned into ultra-bright shift-up lights.
Yet for all the appeal of the charismatic new engine it's the suspension revisions that have done most to transform the GT350 into a proper performance car; one that doesn't need any of the usual "for a Mustang" provisos. It's much more agile and responsive than the standard car, grippier and far more composed, doing a superior job of dealing with rougher roads despite riding on firmer suspension. Switchable dampers are part of the optional $6,500 'Track Pack', which was fitted to the car I drove, but even in their firmer Sport setting these are not too harsh. Tyres are bespoke Michelin Pilot Super Sports, and although the basic electric power steering system is the same as the standard Mustang, unique tuning and revised front suspension geometry give more direct responses and noticeably crisper feel.
It takes a few miles to realise what the combination of a high-revving naturally aspirated V8 and a properly sorted chassis is reminding me so strongly of. Don't laugh, but it's the E92 BMW M3. Granted, the GT350 doesn't possess quite the same level of Teutonic finesse, but it has a similarly well-judged balance between engine and chassis, with the relative lack of low-down torque meaning it can be driven hard with the stability control system either switched to its more permissive Track mode, or even sent to the kennel, without worrying about unscripted sideways moments. Of course, if you do want to make things turn smokey, the GT350 is equally happy to oblige.
I also got to drive the harder-cored GT350R, although only on road rather than the track environment it's really designed for. The R is another $13,500 on the GT350, losing rear seats and around 60kg of weight through various lightweight parts, including carbon fibre wheels. It rides on super sticky Pilot Sport Cup tyres and gets an even firmer suspension set-up, has the switchable dampers as standard and even boasts a carbonfibre rear wing that's claimed to deliver positive downforce.
We probably shouldn't even mention prices when it comes to reviewing US models in the US. It's a cruel tease, even if they did cross the Atlantic the asking would always end up being vastly more than anything close to a direct translation. But, for the record, the GT350's $49,995 is £32,800 at current exchange rates. In the 'States a BMW M4 is $66,395 unoptioned, and by contrast the Mustang looks like an outrageous performance bargain.
Perhaps more realistic perspective comes from considering the Mustang V8 GT's $33,000 base price in the US. That's not too much of a supplement for what is undoubtedly the best handling Mustang that Ford has ever built. Now we just need to persuade them to bring it over here.
Watch the video here.
FORD SHELBY MUSTANG GT350R
Engine: 5,163cc V8
Transmission: Six-speed manual, rear-wheel drive
Power (hp): 526@7,500rpm
Torque (lb ft): 429@4,750rpm
Top speed: N/A
Weight: 1,658kg (GT350: 1,705kg)
MPG: 16 (EPA-estimated)
Price: $63,495 (GT350 $49,995)