Confessions of an Automationeer, Part 14: Going Unreal

Confessions of an Automationeer, Part 14: Going Unreal

Since the release of the Unreal Engine 4 version of Automation into the open beta testing phase, many users have switched to it and immediately begun reveling in the massive improvements in realism, replayability, and audio/visual quality. However, as of the date this post was published, I have not opted into the open beta yet. Why? It turns out that, even after four major updates, there are still quite a few bugs, some of which can actually cause the game to crash. Nevertheless, I am still seriously considering making the switch, although I would prefer to wait until the UE4 build is polished enough before I transfer to it permanently.

So how am I going to start off in the UE4 version of Automation, after two years of using the Kee engine version? First off, I can't remake the entire histories of any of my brands straight away - that will have to wait until all of the mods required for their models have been remade for UE4. Instead, I will create a few test cars using the default bodies - and probably make a new brand or two. Secondly, the introduction of new engine and trim options will inevitably force me to experiment with them - although to be fair, their unavailability in the Kee engine version has not affected my companies' lore very much, if at all. Finally, the introduction of a photo studio to the sandbox mode will allow me to explore hitherto unavailable options for screenshots, especially with the introduction of a revamped exterior color selector.

In short, while the UE4 release of Automation is still very much a work in progress, the benefits of opting into its open beta testing phase will eventually be too great to pass up. However, until I can clarify my UE4 plans further, and enough mods have been remade, I will continue to use the Kee engine version, not just for forum challenges, but for developing my companies' lore further before all of it - not just the most important bits - can finally be remade. To all Automationeers who have already joined the UE4 open beta, I wish you the best of luck.

Confessions of an Automationeer, Part 13: The Myth of the Straight-Six Supercar

Confessions of an Automationeer, Part 13: The Myth of the Straight-Six Supercar

As described my the previous post, the straight-six engine is making a comeback in the real-life automotive industry after decades of being overshadowed - and replaced - by more compact and supposedly cheaper-to-develop V6 engines. Having described the benefits of inline sixes compared to equivalent V6s, I set myself a challenge involving the use of such an engine, but it wouldn't be for a mass-market volume model. Instead, I would attempt to prove that a supercar or hypercar powered by a straight-six engine could be a competitive offering.

The SMG Hissho: Rolling proof that inline sixes still belong in the engine bays of supercars and hypercars... contrary to popular belief.

To complicate matters even more, I had decided to prioritize light weight and high efficiency over outright performance for this build. Fortunately, the body I chose had excellent aerodynamics, which helped greatly during the engineering phase. The design phase was quite simple, though; I ended up building a car with relatively clean, uncluttered styling in which the side intakes were placed next to the rear window, rather than on the car's flanks. Eventually, I called my car the SMG Hissho LS; Hissho is Japanese for "certain victory" and LS is short for "Lightweight Spec".

500 horses, plenty of torque and not too thirsty for a turbo six... what's not to like about this engine?

The Hissho's turbocharged straight-six had a magnesium block and ran 1.25 bar of boost on premium unleaded. Careful tuning yielded a fairly flat, wide torque curve and 500 horsepower at 7600 rpm, with a redline of 8000 rpm. And with its undersquare dimensions, the engine still weighed less than 200 kilograms even with the turbo hardware included. Having finalized the engine specs, I was now ready to focus on the rest of the car.

In keeping with my aim of making a light car, the body, chassis and wheels were made out of carbon-fiber, while the interior was relatively pared back and covered in lightweight materials. To harness the engine's considerable torque output, the Hissho had an electronically controlled differential, rear spoiler, and dampers. These advanced technologies, combined with the low curb weight of 1.3 metric tons, ensured that the Hissho's dynamics were excellent, with minimal body roll. Moreover, it achieved 30 mpg (US) on the combined cycle - an unusually high figure for a supercar) thanks to careful selection of gear ratios and spacing. And yet, against all odds, at its pre-markup price, it achieved a competitiveness score of over 100 in the two regions in which it could be sold.

Immediately, however, I began wondering how good the Hissho was. As it turned out, I had already built many similar designs to the Hissho over the past few months; this one, though, didn't rely too heavily on quality sliders, as some of those builds did. Even so, I secretly believed that, for a car like this, 500 horsepower wouldn't always be enough. For this reason, shortly before I began work on this economy-oriented build, I decided to take the idea to its logical conclusion. The result was surprising, to say the least.

A concept build of a more extreme six-cylinder hypercar, with ~700 horsepower.

Unlike the Hissho, this earlier build was created with the aim of determining how much power could be squeezed from a straight-six engine given the small engine bay in the body I had chosen. It seemed easier said than done, given the fact that a straight-six is much longer than an equivalent V6, but eventually, I managed to extract a whopping 700 horsepower from a highly undersquare 3.5-liter straight-six. The resulting engine is shown below.

700 bhp from a 3.5L turbo I6? Incredible!

By most objective performance standards the Hissho would have been no match for the bright orange wedge I had made, although the extra torque (and the additional turbo lag that comes with it) made it far less drivable. Nevertheless, it seems fair to consider this test build as a great car in its own right. This is especially apparent when one takes into account the fact that the trim shown here was derived from a less powerful version, aimed at the lower end of the market, but I chose not to show it here because I felt that the Hissho was more deserving of a place on this blog.

That concludes my discussion of straight-six-powered, mid-engined supercar builds, but I won't be done with this engine configuration for some time yet. In the next post, I will explain my plans for the UE4 release of Automation, which is already in open beta.

Confessions of an Automationeer, Part 12: The Joy of Six

Confessions of an Automationeer, Part 12: The Joy of Six

For eight of the past ten CSR rounds I have entered, my entries were powered by a straight-six engine. Now you may be wondering whether or not I am biased towards this particular engine configuration. In truth, I certainly am not, but have done my homework about the pros and cons of the various engine configurations available in Automation. So, without further ado, here's an example of a (turbocharged) straight-six done right, provided by another user who was willing to share his secrets.

The turbo setup for the winning entry in CSR41

Look at the dyno sheet in the screenshot above and you'll see that the torque curve is very smooth, wide and flat, with minimal lag. For this to occur, small-diameter compressors and turbines have to be used in conjunction with a high AR ratio and low boost pressure. The latter, especially when combined with a high compression ratio, allows for further improvements in efficiency; moreover, the use of a lean air-fuel ratio and conservative ignition timing make this engine even more economical.

On top of that, the low-RPM cam profile is very mild, while the high-RPM cam profile is fairly aggressive. However, due to budget constraints, this engine has a simple air-to-air intercooler and a standard three-way catalytic converter. Installing a water-to-air intercooler (which lowers the engine's minimum required octane number, thereby allowing the compression ratio to be increased even more) would cause efficiency to increase further, while a less restrictive high-flow converter would have a similar effect. So it's not hard to see why four of the eight straight-sixes I made during the past CSR were turbocharged.

But even without turbochargers, straight-sixes are preferable to V6s for several reasons. Whereas a V6 has its cylinders arranged in two banks of three, a straight-six has its cylinders arranged in a straight line. The former needs a bank angle of 120 degrees - too wide for most engine bays - to be inherently balanced, and as such, most V6 engines have either a 90-degree bank angle (which leads to less refinement and more complication, even if the resulting engine was derived from a V8) or a 60-degree bank angle (smoother, but more expensive to develop).  Moreover, a straight-six suffers from reduced friction losses compared with an equivalent V6, and also requires fewer components. Finally, it will be easier and cheaper to develop a straight-three or straight-four from a straight-six if they all share the same internal dimensions. The only advantage a V6 has over a straight-six with the same dimensions is its reduced length, and as such, it only makes sense to use one if the engine bay is particularly small.

In short, when budgets are relatively modest and efficiency is key, but a modicum of performance is desired, the sweet spot among engine configurations doesn't always lie with eight cylinders or more, or, for that matter, five or fewer. It can be found in the humble straight-six, and this once-commonplace arrangement looks set to make a comeback. In the next post, I will show a recent build in an attempt to prove that even a supercar (or hypercar, for that matter) can use this relatively humble configuration and still remain competitive in the cutthroat Automation market.