We love ourselves an unusual engine here at CT, regardless of the intended application. That’s why a few weeks back we took a look at the world’s first V12 outboard engine, and today, we want to talk about something designed to propel a lorry.

It’s no ordinary power plant, however - this unit from Achates Power is one that sounds increasingly obscure the more you read the description. It’s a 10.6-litre, two-stroke, three-cylinder, six-piston diesel engine. You read that correctly - six pistons in three cylinders since this is an opposed-piston engine.

Unlike a horizontally-opposed ‘boxer’ engine, which mounts the pistons pointing outwards at 180 degrees in separate cylinders, an opposed engine involves a pair of pistons facing each other and sharing a cylinder. Each piston very nearly meets in the middle at top dead centre, at which point ignition sends both back to bottom dead centre. Two crankshafts at either end are linked via a set of gears, providing power to the transmission.

In theory, this is great. Normally, a load of energy is wasted through the cylinder head, but in an opposed-piston engine, it’s shared between the pistons with more minimal losses. Instead of a cylinder head, there are gaps on one side of the engine for exhaust gas flow and some at the opposite end for intake air. Ditching the head also means fewer moving parts, potentially increasing reliability and decreasing manufacturing costs.

This isn’t a new concept - two-stroke opposed-piston engines were about years ago, but it’s only now that a comeback has been proposed. Achates’ ‘OP’ engine isn’t just an idea, either. A 2.7-litre prototype powering a Ford F-150 pick-up laid the groundwork, and from July in California, Walmart will be testing the 10.6-litre version in a Peterbilt 579. John T. Walton, the late Walmart heir, co-founded Achates with physicist James Lemke in 2004.

One inevitable downside of stacking pistons on top of each other is how tall the package ends up being, but according to Achates, this won’t be much of an issue in big Class 8 trucks. All being well, the OP will be a cost-effective alternative to upgrading existing 13 and 15-litre four-stroke engines for stringent Environmental Protection Agency (EPA) rules due to come into force in 2027.

It was announced late last year that the OP will comply with the new regulations. Currently, Achates says its testing has shown a seven per cent drop in CO2 emissions and a whopping 96 per cent NOx reduction compared to a conventional lorry engine. Despite this, the 10.6-litre engine used in Walmart’s demonstration vehicle is good for around 400bhp and 1674lb ft of torque.

Fully electric lorries, of course, would be greener still, but given the hurdles there in terms of range/battery technology, something like the OP could be the perfect interim solution. It’ll be fascinating to see how this pans out.

We’d wager 'Carolina Squat' is a relatively new term in the automotive space. Inspired by the long-travel suspension from Baja Trophy Trucks, the trend involves truck owners lifting the front suspension and lowering the rear. It provides the same squat that desert racers use to offer extra compliance during aggressive suspension compressions, allowing the rear wheels to strike first after a jump.

North Carolina recently introduced a bill to put an end to the peculiar trend. It prohibits elevating the front suspension more than three inches while at the same time lowering the rear by more than two inches. The exact reasoning behind the bill is unknown, but we’d wager that visibility and headlight angle played a role in the decision.

Despite being called the Carolina Squat, the trend actually originated on the Baja California Peninsula, where races like the Baja 1000 take place. However, unlike those high-performance offroad racers, the latest trend is highly impractical for road vehicles. Aside from the obvious safety concerns, road-going vehicles don’t have to navigate gnarly bumps at over 100 miles per hour.

Aside from not having nearly as much suspension travel, it’s important to note that none of the current factory high-performance trucks come with any squat. Hot rods like the F-150 Raptor and Ram TRX come with the same ride height at both ends – we’ve also seen both trucks successfully take impressive jumps without any issues.
A Reddit feed about the trend shows that there have been multiple incidents where Carolina Squatters have rear ended stationary vehicles that they simply couldn’t see. Details remain sparse, but it looks like the trend gained steam after taking Instagram by storm.

The Clarkson Review: BMW M3 Competition
Thanks to BMW, I’ve been having a field day

Jeremy Clarkson

Sunday April 04 2021, 12.01am BST, The Sunday Times

It makes me sad when people say that electrical cars can be fun, because of course they can’t. Take away the sound of internal combustion and the vibration and the weird torque characteristics, and you’re left with something that’s not even on nodding terms with the concept of fun.

Sure, an electrical car can be very fast but so what? For thrills, I’d rather do a hundred in a Sopwith Camel than five hundred in a Boeing 777. I’d rather do twenty knots on a jet ski than thirty on a cruise liner.

And then there’s this: a microwave oven will bake a potato in five minutes and that’s very clever, but the end result will be nowhere near as satisfying as something that’s been in the Aga for two hours.
There are many people in my line of work who think that electrical cars can be enjoyed by enthusiasts just as much as those that use petrol to move about. They are wrong. Because when we are forced by law to drive around in glorified milk floats, we will simply buy whatever gives us the greatest range or the best value. Cars will become wheeled fridge freezers. Tools. And the spirit of the car, its core, will be dead.

Don’t believe me? OK, watch that car chase in Bullittwith the sound turned off.

And there’s more. Last weekend, an old mate who runs a company called Prodrive called round with a car he’d made. Financed by the Bahraini royal family and built in Banbury, it was a huge and ungainly looking thing that had come fifth in this year’s Dakar rally. Next year it will probably win it, and after that there will be versions for the army and, better still, models you can buy. If you have £750,000 lying around. And a desert to use it in. I don’t have a desert but I do have a farm and so last Saturday I was to be found several feet in the air going “yeehah” a lot.

Powered by the same turbocharged V6 they use in the Ford GT, it’s not the fastest car in the world, but it will happily sit at 112mph, all day, while going across Saudi Arabia’s barren and bumpy interior. So it can easily soak up the worst bits of Oxfordshire and it did, while sideways and with a fat man in the driver’s seat, grinning.
Doubtless I was in contravention of many soil compaction regulations, but it was just so liberating to be out there power sliding round the winter wheat in an orgy of free thinking and optimism and fun. To be driving for the sheer joy of driving. And changing gear for the aural reward.

A millennial or a snowflake would claim, if they saw this enormous monster tearing by, that I was a climate change denier. And there’d be no point explaining that a new version designed to run on hydrogen is in the pipeline because they wouldn’t listen. They don’t listen. Because it’s their right to live in a world where everyone agrees with everyone else and nothing noisy ever happens.

All of which brings me on to the new BMW M3 Competition. There must be a sense in the back rooms of the world’s car companies that there’s no point going the extra mile in the development of superfast sports saloons because the end is nigh. It’d be like completely reworking a Nigel Gresley Pacific, just before the Deltic came along.*
In fact we can already see the writing on the wall because BMW will not be selling the ordinary M3 in Britain, just the “Competition” version. And no manual gearbox is on offer either. It seems then that the new M3 is a teatime bun, just something to fill a gap until the reaper arrives.

They haven’t even been very sensible with the price. Someone at a meeting just went “seventy-five grand?” And everyone just nodded and went back to skimming through TikTok.

But wait, what’s this? The twin-turbocharged straight-six engine is broadly the same as it was but almost all of the internals are bigger and stronger and more racy. This means 60 more horsepowers than you got in the old model, and 73 more torques.

There’s a whole new styling direction too, with a Pontiac-style nose and a grille so large you could go on holiday in it. The whole car’s bigger too, noticeably so, but the essence of M3 is still very much in evidence. There’s a sense that the body has been stretched to fit over the wheels, which incidentally are now bigger at the back than they are at the front. This, you start to realise, is not a coffee-break car that was half-heartedly thrown together on the back of a *** packet.

And then you step inside, where you are greeted with new seats — the best I’ve ever sat in. They’re even better than the ones in a Renault Fuego turbo. And a whole new dash that does all sorts of new things. Like, for example, you can set the rules for your air conditioning system. And how German is that.

There is also a device that measures and then rates your drift. Seriously, you power-slide round a bend and it will give you marks. Not sure this sort of thing is, or should be, legal, but it’s a hoot to know it’s there. And a hoot to know that absolutely every single person who uses it will — moments after saying to their passenger “Right, watch this” — definitely get a ride in an air ambulance.

That’s the thing about skidding on purpose. You can get away with it once, or twice, or maybe even two hundred times. But eventually you’re going out in a blaze of splintering sounds and swear words.
It may, however, be five hundred times in the M3 because, ooh, this is a fine-handling car. I didn’t much care for the steering set-up on the previous model — it worked well only in “comfort” mode — but much work has been done in the new version and it’s sublime. As is the grip. And what happens when that grip is breached.
Maybe, just maybe, the gearbox is slower than the old flappy paddle manual but you have to be paying attention to notice. The thing about five hundred horsepower, though, is it has the ability to mask these things. And it does. Beautifully.

This is one of those cars, like the Alfa Romeo Giulia Quadrifoglio, that just glides from corner to corner on what feels like a wave of telepathy and poise and pit-of-the-stomach excitement. It’s balletic.
And comforting, because it means that BMW’s engineers are not going to sit through their final days shrugging and reminiscing. They want to go out in a blaze of glory. We can only hope other carmakers do the same thing, and that before they’re all made to work for Zanussi’s automotive division making stuff to fill the windows at Currys, they remind us all why it was they wanted to be car engineers in the first place.

*Only James May would understand this

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