Confessions of an Automationeer, Part 6: Defending My CSR33 Entry
Having sat out the previous round to allow my mind to relax after 17 consecutive rounds of participation (either as an entrant or host), I decided to regroup and prepare myself for CSR33, in which competitors were tasked with building a junior executive car for the 1998 model year. Straight away I reverted to an engineers-first mindset, but after realizing that the car would have to be engineered in 60 months and require no more than 100 production units, I was forced to make a few compromises. The question now was: what should I leave out in order to squeeze the fancier bits in?
When I found out that the design brief called for an entry-level premium car, I thought about making a premium interior, sound system, and safety suite all standard equipment, but ultimately realized that the tight engineering budget would make it impossible. So I settled on a more reliable standard interior instead. I also omitted stability control (but retained traction control) for the same reason - although back in 1998, it most certainly wasn't the universal driving aid it is now. And to compensate for the omission of premium equipment, I explicitly stated in the car's description that it was optional on the trim I would eventually submit.
The chassis and drivetrain configuration also gave me a few headaches. Originally, I wanted my CSR33 entry to be front-wheel-drive (and in fact, many of the submitted entries were), but quickly changed my mind after deciding that I would rather emphasize sportiness, and switched to rear-wheel-drive. Also, the suspension started out as struts up front with a torsion-beam rear, but the latter was replaced with semi-trailing arms, and eventually I opted for control arms at both the front and rear. However, I discovered that I still had some engineering time to spare, and used some of it to install a multilink rear instead, thus improving drivability, sportiness and comfort even further with minimal loss of reliability.
Designing an engine for the car was no cakewalk either. With the maximum engineering time and production units for an eligible engine capped at 80 each, I was forced to rule out any configuration with more than six cylinders in it, and settled on a straight-six with dual overhead cams, variable valve timing and lift, low-friction pistons, and 2550 cc of displacement. I did, however, ask myself one question: Would a straight-four have been as effective? The answer turned out to be a definite no: the loss of sportiness and prestige clearly outweighed the increase in economy it would have provided. Moreover, I used a normally-aspirated engine, since a turbocharged one would have put me well over budget in terms of engineering time, and even if it didn't, I would sacrifice too much drivability in the process. I was quite happy with how it turned out, though.
As for the remaining trim components, I made choices that would prioritize sportiness over comfort, but kept the use of quality points to a minimum, although negative quality was out of the question. Specifically, the manual transmission made the car harder to drive and reduced the comfort rating, but provided a significant boost to sportiness, while the fitment of all-season tires were ideal for this car's role as a daily driver - high-performance tires would have been at odds with the design ethos if I had offered them as standard, even though it would have increased the sportiness rating even more. In addition, I opted for a combination of a viscous limited-slip differential and vented disc brakes (two-piston calipers up front and single-piston calipers at the rear, plus an anti-lock braking system), providing a well-rounded balance between drivability, sportiness, affordability (both in terms of engineering time and estimated price) and comfort. Finally, I tuned the suspension (which incorporated progressive springs, passive anti-roll bars and monotube dampers) to provide a sporty feel while retaining the drivability and comfort levels expected of a daily driver.
With the mechanicals and trim now definitively sorted, I was left to finalize the exterior design. However, considering that the car's looks had to convey the right image, the shape, quantity and placement of the fixtures was crucial. After all, entry-level executive cars ought to exude a form of restrained elegance without being too bland or, on the other hand, excessively ostentatious. As such, I decided to keep it simple on the outside, and jazz up some of the fixtures with some chrome trim.
Moreover, the car's exterior color also had to befit its image, and I went with a dark, lustrous red which I called Deep Claret Metallic - I could have chosen a deep blue or green instead for a similar effect, but I stuck with red anyway because I believed it felt more upscale than the other two. I also found black to be too intimidating, silver or gray to be too dull, and white to be too flashy. And I deliberately extended the rear end as much as the body will allow me to in order to increase the amount of cargo space available, and raked back the A- and C-pillars quite a fair bit to give a sportier side profile.
When I found out that the design brief called for an entry-level premium car, I thought about making a premium interior, sound system, and safety suite all standard equipment, but ultimately realized that the tight engineering budget would make it impossible. So I settled on a more reliable standard interior instead. I also omitted stability control (but retained traction control) for the same reason - although back in 1998, it most certainly wasn't the universal driving aid it is now. And to compensate for the omission of premium equipment, I explicitly stated in the car's description that it was optional on the trim I would eventually submit.
The standard equipment list on the Kramer K3 2.5. Note that a premium interior and safety suite (incorporating stability control), though not selected here, are stated to be optional.
The chassis and drivetrain configuration also gave me a few headaches. Originally, I wanted my CSR33 entry to be front-wheel-drive (and in fact, many of the submitted entries were), but quickly changed my mind after deciding that I would rather emphasize sportiness, and switched to rear-wheel-drive. Also, the suspension started out as struts up front with a torsion-beam rear, but the latter was replaced with semi-trailing arms, and eventually I opted for control arms at both the front and rear. However, I discovered that I still had some engineering time to spare, and used some of it to install a multilink rear instead, thus improving drivability, sportiness and comfort even further with minimal loss of reliability.
Originally intended to be a front-driver with a transversely mounted engine, a strut-sprung front and torsion-beam rear, the Kramer K3 2.5 emerged as a rear-driver with a longitudinally mounted engine, double wishbones up front and a multi-link rear - and all the better for it.
Designing an engine for the car was no cakewalk either. With the maximum engineering time and production units for an eligible engine capped at 80 each, I was forced to rule out any configuration with more than six cylinders in it, and settled on a straight-six with dual overhead cams, variable valve timing and lift, low-friction pistons, and 2550 cc of displacement. I did, however, ask myself one question: Would a straight-four have been as effective? The answer turned out to be a definite no: the loss of sportiness and prestige clearly outweighed the increase in economy it would have provided. Moreover, I used a normally-aspirated engine, since a turbocharged one would have put me well over budget in terms of engineering time, and even if it didn't, I would sacrifice too much drivability in the process. I was quite happy with how it turned out, though.
An overview of the 2.5-liter straight-six used in my CSR33 entry. This engine is optimized for economy but still develops a decent amount of power at a low price.
As for the remaining trim components, I made choices that would prioritize sportiness over comfort, but kept the use of quality points to a minimum, although negative quality was out of the question. Specifically, the manual transmission made the car harder to drive and reduced the comfort rating, but provided a significant boost to sportiness, while the fitment of all-season tires were ideal for this car's role as a daily driver - high-performance tires would have been at odds with the design ethos if I had offered them as standard, even though it would have increased the sportiness rating even more. In addition, I opted for a combination of a viscous limited-slip differential and vented disc brakes (two-piston calipers up front and single-piston calipers at the rear, plus an anti-lock braking system), providing a well-rounded balance between drivability, sportiness, affordability (both in terms of engineering time and estimated price) and comfort. Finally, I tuned the suspension (which incorporated progressive springs, passive anti-roll bars and monotube dampers) to provide a sporty feel while retaining the drivability and comfort levels expected of a daily driver.
In setting up the K3's mechanicals, I optimized its sportiness while also retaining a decent amount of comfort and drivability.
With the mechanicals and trim now definitively sorted, I was left to finalize the exterior design. However, considering that the car's looks had to convey the right image, the shape, quantity and placement of the fixtures was crucial. After all, entry-level executive cars ought to exude a form of restrained elegance without being too bland or, on the other hand, excessively ostentatious. As such, I decided to keep it simple on the outside, and jazz up some of the fixtures with some chrome trim.
Moreover, the car's exterior color also had to befit its image, and I went with a dark, lustrous red which I called Deep Claret Metallic - I could have chosen a deep blue or green instead for a similar effect, but I stuck with red anyway because I believed it felt more upscale than the other two. I also found black to be too intimidating, silver or gray to be too dull, and white to be too flashy. And I deliberately extended the rear end as much as the body will allow me to in order to increase the amount of cargo space available, and raked back the A- and C-pillars quite a fair bit to give a sportier side profile.
The Kramer K3 2.5 is known for its stylish exterior... and a huge trunk.
Only time will tell if my enthusiast-focused approach delivers a satisfactory result, but I am certainly going to take pride in what I have built and submitted for this round. For one, making compromises when there is a maximum limit on production units and/or engineering time for the car and/or its engine is not easy, and success here often boils down to using the right equipment. In the lite campaign, where profitability hinges on releasing your cars soon enough to boost sales, this is even more important. As for the results of the current round... well, that will have to wait until the next post.
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