The Truth About Cars » Engineering http://www.thetruthaboutcars.com The Truth About Cars is dedicated to providing candid, unbiased automobile reviews and the latest in auto industry news. Sat, 02 Aug 2014 03:20:50 +0000 en-US hourly 1 http://wordpress.org/?v=3.9.1 The Truth About Cars is dedicated to providing candid, unbiased automobile reviews and the latest in auto industry news. The Truth About Cars no The Truth About Cars editors@ttac.com editors@ttac.com (The Truth About Cars) 2006-2009 The Truth About Cars The Truth About Cars is dedicated to providing candid, unbiased automobile reviews and the latest in auto industry news. The Truth About Cars » Engineering http://www.thetruthaboutcars.com/wp-content/themes/ttac-theme/images/logo.gif http://www.thetruthaboutcars.com Piston Slap: Hella Sweet Engineering at The 24 Hours of LeMons http://www.thetruthaboutcars.com/2013/06/piston-slap-hella-sweet-engineering-at-the-24-hours-of-lemons/ http://www.thetruthaboutcars.com/2013/06/piston-slap-hella-sweet-engineering-at-the-24-hours-of-lemons/#comments Mon, 17 Jun 2013 12:00:26 +0000 http://www.thetruthaboutcars.com/?p=492311 Aside from the great friendships forced via encouraged bribing that naturally occur when like-minded people congregate, the 24 Hours of LeMons is a fantastic opportunity for those wearing a Judge’s robe. Take last month’s race at Eagles Canyon Raceway: when stupid (yet purposeful) things like this Flavor Flav clock on the dash of this Mitsubishi […]

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Aside from the great friendships forced via encouraged bribing that naturally occur when like-minded people congregate, the 24 Hours of LeMons is a fantastic opportunity for those wearing a Judge’s robe. Take last month’s race at Eagles Canyon Raceway: when stupid (yet purposeful) things like this Flavor Flav clock on the dash of this Mitsubishi Eclipse arrive, I can’t help feeling like I’m hosting “Pimp My Ride LeMons” edition…

While Xzibit makes hilarious faces/comments as the kids talk about their hooptie’s general crappiness, I just snap a photo and begin judging them…so click the link to see more hilarity.

photo 1 So what is a rotary tool doing on the firewall of this Honda product?  That was my question…and the answer is astounding.

Apparently Honda’s EFI system uses a VSS (vehicle speed sensor) that is rather expensive to fix.  And fix it you must! When the VSS fails to report vehicle speed, Honda’s computer freaks out: going into a reduced performance, limp-home mode.  An inconvenience for most folks on the street, but a killer for a race car.  So what’s the fix on a $500 budget?  Attach a Dremel-style rotary tool to the firewall, turn it on and let it spin the VSS’s cable instead!

Wanna know what makes this even funnier?  The re-engineered, V2.0 implementation of this VSS workaround includes an ON/OFF switch on the dash!  Get in the car, put your helmet on, strap yourself in, fire up the motor…and wait for it…don’t forget to turn on the Dremel!

Re-engineering a brilliantly half-assed workaround is a fantastic notion. Such is the beauty of the $500 race car!

photo 3

This is the alternator of a Fox Body Mustang with the “twin spark” 2.3L four banger.  Said motor emitted a horrible shriek on occasion.  Upon closer inspection, the Mustang’s owners decided that zip ties were an adequate substitute for a proper nut and bolt.  Which apparently was lost at some point in the car’s life.

Surprise, surprise: the shriek went away after installing the correct hardware.  What would Xzibit say at this moment?

photo 4

This V6 Mustang is designed-owned by a pair of unbelievably intelligent engineers.  Very nice dudes who “get” the concept of a LeMons car, to boot.  These engineers, in the spirit of a $500 car, avoided the easy route of buying fancy shocks, painting them black and hoping we didn’t notice their performance on the bounce test.

The engineers said they had two good street shocks, and two horrible ones.  Combine the two (on a completely unnecessary Ford 9″ rear for what reason?) and you get adequate race dampers on the rear axle. Also note the adjustable panhard bar mounting points: very cool, but not very funny.

The shocks are completely in the spirit of LeMons, so I’m suitably impressed.  Laughing, but still impressed.

 

photo 5

Say you got a last-gen Mazda RX-7 turbo (FD bodystyle) for $500 after it caught on fire and became essentially worthless to any street going Rotary fan.  Say you spent a ton of money making it into a legit race car.  You probably don’t have much more left in the kitty for necessary body items to make an FD worthy of an endurance race. (And trust me, it wasn’t. Don’t fill the comments section with BS about how this car isn’t a worthy LeMons car)

This RX-7 was assembled in a matter of days, not months.  I was blown away at the “quality” of work, including this awesome home HVAC intake grille being used at a cooling grate for the RX-7′s turbo mill. I mean, why not use one of these if you have it lying around?

Conversely, you need to block off the gaping hole where the FD used to sport its trademark pop up headlights. One can assume the lights were stripped to help make this into a credible $500 purchase. Vinyl flooring makes for a great headlight alternative…especially at only $1.50 a headlight!

 

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Wild-Ass Rumor Of The Day: Chrysler Job Ads Point To Next Wrangler Details http://www.thetruthaboutcars.com/2013/05/wild-ass-rumor-of-the-day-chrysler-job-ads-point-to-next-wrangler-details/ http://www.thetruthaboutcars.com/2013/05/wild-ass-rumor-of-the-day-chrysler-job-ads-point-to-next-wrangler-details/#comments Fri, 24 May 2013 20:53:57 +0000 http://www.thetruthaboutcars.com/?p=489543 Is the next Jeep Wrangler getting a diesel? What about an air suspension? It’s looking that way, at least according to Automotive News. Larry Vellequette, who covers Chrysler for the publication, looked at a number of job ads and theorized that based on the skills required and the upcoming product timeline, they are related to […]

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Is the next Jeep Wrangler getting a diesel? What about an air suspension? It’s looking that way, at least according to Automotive News.

Larry Vellequette, who covers Chrysler for the publication, looked at a number of job ads and theorized that based on the skills required and the upcoming product timeline, they are related to work on the next generation Jeep Wrangler.

 

Vellequette seems to think that the Wrangler, like the Ram, will get a big weight reduction thanks to high strength steel in its frame. A diesel engine, an air suspension and an 8-speed automatic transmission also seem to be in the cards.

Some of the Wrangler’s idiosyncratic trademarks are also being examined too

Engineers also will look at the Wrangler’s unique closure systems — the clip-down hood, for example, or its somewhat-inviting-to-thieves exterior door hinges.

What’s not clear is whether the next Wrangler might include a permanently fixed wind screen. Only a small percentage of Wrangler owners ever go through the trouble of dropping their wind screen, but eliminating the ability to do so would allow engineers to increase its rake and with it, the Wrangler’s fuel economy.

Vellequette notes that Jeep engineers have an unenviable task; balancing the need to maintain the Wrangler’s signature design cues and off-road capabilities with the realities of CAFE. In many ways it is Chrysler’s most important product launch, both from a marketing standpoint and from a sales one too (try finding a Wrangler Unlimited on a dealer lot – it’s not easy).

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Carnegie Mellon Researchers Invent Smart Headlights That “See Through” Rain, Snow http://www.thetruthaboutcars.com/2012/07/carnegie-mellon-researchers-invent-smart-headlights-that-see-through-rain-snow/ http://www.thetruthaboutcars.com/2012/07/carnegie-mellon-researchers-invent-smart-headlights-that-see-through-rain-snow/#comments Fri, 06 Jul 2012 15:01:12 +0000 http://www.thetruthaboutcars.com/?p=451478 The problem with driving at night in the raining or snowing conditions is that your headlights work too well. They light up the rain and snow as much as they illuminate the road ahead, sometimes more so. In a novel approach using cameras, computers and DLP projectors to replace conventional headlight bulbs, researchers at Carnegie […]

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Click here to view the embedded video.

The problem with driving at night in the raining or snowing conditions is that your headlights work too well. They light up the rain and snow as much as they illuminate the road ahead, sometimes more so. In a novel approach using cameras, computers and DLP projectors to replace conventional headlight bulbs, researchers at Carnegie Mellon University have developed a “smart” headlight system that essentially shines light between the rain drops.

It turns out that less really can be more, at least in terms of night driving. By selectively reducing the amount of light projected, by not shining light on the computer predicted path of the rain drops or snow flakes as they enter the critical 3-5 meter space in front of the driver, there is significantly reduced glare.

Theoretically in a perfect system with minimal latency, illuminating 100% of rain drops would come at a cost of only a 2% reduction in total light projected. Precipitation is only a small fraction of the total visual field. So far in lab tests with real water drops falling at normal precipitation levels and slow (30KPH) travel speeds, they can reduce the visibility of rain almost 70% at a cost of only 5% loss of light. The system is less efficient with snowflakes, because they are larger and move more slowly, so there’s about about 15% loss of light, but it can still keep from illuminating more than 60% of the snow. At higher speeds it’s less efficient but lead researcher Srinivasa Narasimhan says that continued development for highway speed use is worthwhile, while stressing that the current system cannot account for wind, turbulence and that it needs to be more compact. Though the researchers stress the data capture and processing parts of the system, it couldn’t work without a DLP projector, one of our age’s unappreciated wonders. The microminiature mirror array in a DLP device can be precisely controlled as to where it shines light.

Ronnie Schreiber edits Cars In Depth, a realistic perspective on cars & car culture and the original 3D car site. If you found this post worthwhile, you can dig deeper at Cars In Depth. If the 3D thing freaks you out, don’t worry, all the photo and video players in use at the site have mono options. Thanks for reading– RJS

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Ask An Engineer: GDI Problems In A Nutshell http://www.thetruthaboutcars.com/2012/05/ask-an-engineer-gdi-problems-in-a-nutshell/ http://www.thetruthaboutcars.com/2012/05/ask-an-engineer-gdi-problems-in-a-nutshell/#comments Thu, 03 May 2012 13:00:11 +0000 http://www.thetruthaboutcars.com/?p=442513 “Ask an Engineer” is hosted by Andrew Bell, a mechanical engineer and car enthusiast. Andrew has his MASc in Mechanical Engineering from the University of Toronto, and has worked on Formula SAE teams, as well as alternative fuel technologies in Denmark and Canada. Andrew’s column will explore engineering topics in the most accessible manner possible. Even though […]

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“Ask an Engineer” is hosted by Andrew Bell, a mechanical engineer and car enthusiast. Andrew has his MASc in Mechanical Engineering from the University of Toronto, and has worked on Formula SAE teams, as well as alternative fuel technologies in Denmark and Canada. Andrew’s column will explore engineering topics in the most accessible manner possible.

Even though every other car nowadays seems to offer gasoline direct injection (GDI), Mercedes-Benz was the first to exploit this technology in the 1955 300SL. But it wasn’t until the mid-1990’s that other automakers started to use GDI in mass produced vehicles. GDI promises marginal increases in fuel economy (3% reduction in BSFC ) but its real benefits include reduced cold start/low load emissions and higher power outputs. While the technology offers engineers incredible flexibility from an engine design perspective, it is not without faults. As with any new technology it is important to understand both the positives and negatives before you choose, say a compact car with GDI or one regular fuel injection. If you want to keep your car for a long period of time, the long-term reliability of a GDI engine is an important factor.

The effect of increased percentages of ethanol on injector longevity.

The percentage of ethanol in gasoline at the pumps is steadily increasing. Ethanol has a tendency to increase the corrosion rate of the various metals used in an engine. Add this to the elevated fuel pressure and the fact the injector is directly exposed to in-cylinder combustion events, and you have a recipe for a recall. Furthermore, these injectors are very sensitive to fuel quality due to outrageously tight tolerances. It is very important to use high quality fuels and keep the filters clean.

Higher pressures in general.

GDI requires significantly higher fuel inlet pressures than port injection. This puts a great deal of strain on every piece of the fuel delivery chain. This is not a problem on a new engine. 50,000 miles down the road, and it may be. Manufacturers have been relatively proactive in this department by specifying robust, stainless steel fuel lines and connections. That hasn’t stopped fuel pump recalls from already occurring

Carbon buildup on intake valves.

This is the big problem with most current GDI engines. Due to modern unburned hydrocarbon (UHC) regulations, vapors from the crankcase are usually vented into the intake stream in order to prevent oil droplets from escaping through the exhaust. In a port injection engine, these droplets are ‘washed off’ the neck of the intake valve by a relatively constant stream of gasoline droplets. In a GDI engine, the gasoline doesn’t touch intake side of the valve. As a result, the droplets have a tendency to bake onto the valve and significantly reduce performance. To add to this effect, many advanced GDI engines also include exhaust gas recirculation in order to lean out the combustion mixture and reduce in-cylinder temperatures for certain combustion modes (reducing NOx emissions). Since GDI combustion has the ability to produce far more soot than premixed combustion (port injection), the problem is magnified.

Even more alarming is that these deposits can dislodge and damage other downstream components (turbochargers, catalytic converters, etc.). Manufacturers have added systems to capture these oil droplets and particulates, but no system is 100% effective. As a result, there are many disappointed early adopters with large repair bills. Even diesel engines haven’t been immune to these issues.

The reason these issues have slipped through to production is that they won’t show up in a 500,000 mile torture test. These types of issues will appear after years of short trips (preventing the engine from reaching operating temperature), bad batches of fuel, etc. As we approach the efficiency limits of the internal combustion engine, the engines themselves (and associated support systems) have become more complex. As with the transition from carburetors to electronic fuel injection, there will be some overlap between relatively bombproof port injected engines and the unproven, first-generation GDI engines.

 

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Piston Slap: Playing Super Breakout by Itself? http://www.thetruthaboutcars.com/2012/01/piston-slap-playing-super-breakout-by-itself/ http://www.thetruthaboutcars.com/2012/01/piston-slap-playing-super-breakout-by-itself/#comments Mon, 23 Jan 2012 14:00:21 +0000 http://www.thetruthaboutcars.com/?p=427725   C.V. writes: I am a mechanical engineering student looking to learn how to work on cars. My friend has given me the opportunity to take his 1988 Mazda B2200 extra-cab 5-speed. When I drove it, I saw why. The catalytic converter has broken off, and apparently pieces of it are in the exhaust. Would […]

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C.V. writes:

I am a mechanical engineering student looking to learn how to work on cars.

My friend has given me the opportunity to take his 1988 Mazda B2200 extra-cab 5-speed. When I drove it, I saw why. The catalytic converter has broken off, and apparently pieces of it are in the exhaust. Would it be possible to just replace the catalytic converter, or should I replace the whole exhaust?

Also while driving it, there is a weird problem. About 10 or so minutes after startup and driving, it starts bucking back and forth as if I was engaging and disengaging the clutch. Any idea as to why that is happening? Theoretically the truck could drive even with this problem, but I don’t think it’s safe or good for the truck. What should I do?

Sajeev answers:

It wasn’t long ago that I was an mechanical engineering student looking to work on cars.  Hell, it’s way more fun than a semester of Thermodynamics, Solid and Fluid Mechanics! So what’s my advice?  Join the Society of Automotive Engineers (SAE) as a student and join the local chapter in your college.  The SAE chapter at the University of Texas changed my life, in a good way. And if you don’t have a chapter?  MAKE ONE!

Oh wait…you wanted advice on the truck, not your career. My bad.

The first problem is pretty easy, replace the convertor. Or not: eventually the loose bits of honeycomb inside will stop playing Super Breakout with itself, exit stage left, and it still might pass an emissions test.  If not, any exhaust shop can slap in a new one, and I just Googled one for $270 that’s a direct replacement.  I am sure you college kids use Google all the time, why not for a sweet little truck?

The second one is usually a combination of a poor gear change technique and a lack of fuel.  Or maybe too much fuel.  Does it buck less if you give it more gas and take more time to let out the clutch?  Problem solved. If not, I’d recommend rebuilding the carb, seafoaming the motor (at your own risk, see YouTube for reasons why), and testing the fuel pressure.  Actually not in that order: start with fuel pressure, then maybe learn how to work on a carb.

Or convert it to a later-model EFI setup! Or even better, LS1-FTW!!! You are an engineer for a reason!

Send your queries to sajeev@thetruthaboutcars.com . Spare no details and ask for a speedy resolution if you’re in a hurry.

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Tiny (12cc) Hand-Machined V12 Is A Holiday Miracle http://www.thetruthaboutcars.com/2011/12/tiny-12cc-hand-machined-v12-is-a-holiday-miracle/ http://www.thetruthaboutcars.com/2011/12/tiny-12cc-hand-machined-v12-is-a-holiday-miracle/#comments Tue, 27 Dec 2011 15:25:08 +0000 http://www.thetruthaboutcars.com/?p=423564 Need an engineering project? Got 1,200 hours to kill with nothing to do? Take a tip from this heroically patient Spaniard, and hand-machine your own tiny (12 cc displacement) V12. This would be amazing feat of handwork even if it weren’t fully operational (using compressed air injection), but the fact that it works, runs and […]

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Need an engineering project? Got 1,200 hours to kill with nothing to do? Take a tip from this heroically patient Spaniard, and hand-machine your own tiny (12 cc displacement) V12. This would be amazing feat of handwork even if it weren’t fully operational (using compressed air injection), but the fact that it works, runs and was made without a single CNC machine is nothing short of astounding.. If, as the book suggests, Shop Class is Soulcraft, this guy is like an engineering bodhisattva, inspiring us with his precision, patience and skill. In a world where not much is made by hand anymore, this achievement is worth taking a few minutes to marvel over… [Hat Tip: Dean Huston]

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Piston Slap: Relevant Lessons taught by Panther Love http://www.thetruthaboutcars.com/2011/08/piston-slap-relevant-lessons-taught-by-panther-love/ http://www.thetruthaboutcars.com/2011/08/piston-slap-relevant-lessons-taught-by-panther-love/#comments Wed, 31 Aug 2011 16:15:59 +0000 http://www.thetruthaboutcars.com/?p=409270   TTAC commentator HeeeeyJake writes: Hey Sajeev, I love the column and I’m a daily TTAC reader, though I rarely comment. We have been a Panther household since the mid nineties, and have had great luck with our vehicles thus far. My parents had two ex-Budget rental Town Cars, a white ’93 with blue interior, […]

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Hey, it coulda happened!

 

TTAC commentator HeeeeyJake writes:

Hey Sajeev,

I love the column and I’m a daily TTAC reader, though I rarely comment. We have been a Panther household since the mid nineties, and have had great luck with our vehicles thus far. My parents had two ex-Budget rental Town Cars, a white ’93 with blue interior, and a medium willow green ’96 with that greyish-beige. I had a pearlescent silver ’91 in high school with black interior and a black canvas top (I added ’02 Cartier wheels , P71 front springs, and a dual exhaust with turbo mufflers). All were zero-problem vehicles. Which brings us to our current Town Car, an ’07 Signature Limited, fresh out of warranty, which is also an ex-rental, but I do not know which company.

The vehicle currently has 30k on it, and has developed a couple of problems. The first is fairly straight-forward: warped rotors. All of our Town Cars seemed to develop warped rotors, but no other vehicles we own ever develop this. I have read that in the 90s, the TCs with 10in brakes were under-spec’d, and saw several sites/forums at that time that recommended swapping out the 12in brakes and caliper from the later models. But with the 07 developing this problem, I’m wondering if all TCs just don’t have enough brakes. The car is driven pretty easily at all times. What is your opinion on that? And what is the best solution? Keep feeding it OEM rotors and pads, swap to P71 calipers/rotors (will they fit and what are the costs involved?-we can do the work ourselves), or is there a good aftermarket rotor that is OEM replacement but is maybe slotted or vented that you recommend for better cooling and to avoid future warping?

The second problem is a weird one. The memory seats/easy exit feature (where the driver seat slides back when the key is moved to the off position) is acting completely bonkers! All seat adjustments work just fine, like tilt, recline, etc. but the fore/aft movement only works about 10-20% of the time, and when it acts up, the seat stays back in the “exit” position with no ability to adjust the seat forward with the power controls on the door. When the memory buttons are pressed, all adjustments take place except fore and aft. It will make a brief and normal noise like it is about to move but doesn’t move. It is textbook intermittent and has no rhyme or reason as to when it decides to work. Is this a common problem? Is it likely the control module/computer has malfunctioned, or is the motor only working intermittently? What should I do here?

My last query deals with suspension tuning. Every since the TCs went to rack and pinion steering and 17inch wheels, they seem to have a sharper steering response. My belief is that they tuned the suspension to the steering response, and they now have too much damping in the shocks and not enough spring. In other words, the driver feels every bump in the road, unlike the older ones, but when bumps are sufficient to cause major suspension travel, they cause a lot of wheel movement, more than the initial dampening would suggest. So it seems that their is a poorly tuned suspension in the new ones, with a bad spring/shock combination. I know you and Jack Baruth have experience with these latest Town Cars, and I’d be interested in both of your thoughts on this issue/theory, if I’m crazy, and what you might recommend to add balance to the suspension tune without sacrificing ride quality.

Thanks so much for your time, I know this is a long one, but that’s Panther love, and when it bites, it sinks its teeth in.

All the best!

Sajeev answers:

Round these parts, rambling on and on about Panthers is falling out of fashion. But a Panther type of platform is a priceless source of knowledge for mechanics, hot rodders and curious onlookers alike.

Question 1: there’s no such thing as Police-specific brakes for Panthers. The forums say that maybe the calipers have steel bores instead of phenolic material, but that’s about it. If you are burning through rotors, maybe a huge batch of them were duds. There’s no logical reason that OEM parts would fail you, and they have yet to fail my Dad’s 2006 Town Car Designer.

More to the point: on a street car, aftermarket slotted /drilled rotors are either negligibly better (if you really cook them on a racecourse) or a complete waste of your money. And forget about the cheap drilled rotors which usually crack if you look at them funny.

Question 2: As far as the seat memory system, check to see if it will also crap out if you activate the fore-aft feature repeatedly from the seat switch. There’s a slim chance that there are relays for the seat motors. If so, odds are the relays are overheating, shutting down and working once again after they cool off. This is a bigger problem in the summer months.

More to the point, this is where you need a factory shop manual. Did you buy one yet? You better!

Question 3: Opinions on suspension systems are like butt holes…everyone has one. But only engineers involved in the game know the hard facts behind the “what” in a platform shall explain the “why” in your quandary. And as if that wasn’t confusing enough, here’s a hybrid of the last two sentences:

My opinion is that the newer Town Cars (the “skinny” ones from the Nasser Era and beyond) have too much spring with not much change in the dampers. My only basis for this is a single data point: a dude who put the soft (front) springs from a “fat Panther” onto his skinny model, removed the rear swaybar and was happy enough to say the end result was a modern Town Car that rode like a proper Land Yacht.

More to the point, you need to dig up the spring rates of all Town Cars. The information is there, somewhere, in specification books for coil springs. If you want softer, you have one data point that sounds credible. If you want the opposite, you have the Mercury Marauder and 1992 Crown Vic Touring Sedan for that.


Send your queries to sajeev@thetruthaboutcars.com. Spare no details and ask for a speedy resolution if you’re in a hurry.

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Mission Creep, Weight Problems, Compromise Haunt GM Alpha Platform http://www.thetruthaboutcars.com/2011/05/mission-creep-weight-problems-compromise-haunt-gm-alpha-platform/ http://www.thetruthaboutcars.com/2011/05/mission-creep-weight-problems-compromise-haunt-gm-alpha-platform/#comments Tue, 17 May 2011 14:52:21 +0000 http://www.thetruthaboutcars.com/?p=395124 Yesterday we gave GM kudos for addressing its lingering vehicle weight issues by redesigning the head of its popular 3.6 liter V6, and shedding 13 lbs in the process. It was, we noted, the kind of news that showed GM is staying focused on the nitty-gritty of product development, sweating the details. But, according to […]

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Yesterday we gave GM kudos for addressing its lingering vehicle weight issues by redesigning the head of its popular 3.6 liter V6, and shedding 13 lbs in the process. It was, we noted, the kind of news that showed GM is staying focused on the nitty-gritty of product development, sweating the details. But, according to a fascinating piece by GMInsideNews, new-product development at GM still has its issues. Specifically, Cadillac’s development of a new BMW 3-Series fighter, known as ATS after its “Alpha” Platform, has faced more than its fair share of what GMI calls “drama.”

Turf battles, unnecessary “wants” on checklists and ultimately a severe case of “Mission Creep” have created a vehicle that now needs a crash diet, according to GMI’s sources both within GM and at suppliers working on the Alpha/ATS program. For a vehicle that’s taking on an institution like the BMW Dreier (not to mention costing a billion dollars to develop), these are troubling signs indeed.

GMI starts with some history of the Apha program, it’s roots as “Kappa II” which Holden showed as the TT36 Torana Concept back in 2004, before development took a long hiatus. As originally intended, Alpha was to be lightweight and enthusiast-oriented, built only for four-cylinder engines. No wonder it went nowhere inside the RenCen until Cadillac adopted the platform as the basis of a forthcoming small sports sedan. But, as it turns out, Cadillac’s “wish list” for Alpha sowed the roots of its runaway complexity and bloat issues. Cadillac may have saved “Kappa II,” but it also killed off its original promise. Here’s how GMI tells the story:

…as Cadillac became involved with the Alpha program, a sense of deja vu came with it. Much like Cadillac’s initial involvement with the Sigma platform, Cadillac had a long wish-list for the new Alpha platform. This long list quickly turned a light, sporty platform on it’s head, including stops on development several times over the last few years.

Initially Alpha was going to be a four-cylinder only chassis for small premium cars, so naturally development focused on optimizing the Alpha platform for four-cylinder mills in a very light package. Well, Cadillac’s first condition was that Alpha be re-engineered to package a naturally aspirated V-6 engine – and that was non-negotiable. This about-face on engine selection would become the first of at least two engine requests that led to a re-engineering of the Alpha chassis to accommodate the new requirements. More changes (read: more mass and cost) were required for the addition of all-wheel drive.

What started out as a great handling, small RWD program, began it’s mission creep from being very focused to being all things to all people. And as it evolved, certain “hard-points” from previous development were locked in, even though the base program had transformed itself. For example, Alpha was designed with a very sophisticated multi-link front suspension with near perfect geometry for the car as it was developed at that point. That geometry was “locked in”. As the car grew and became heavier with more features and content, that original geometry was no longer optimal. Our sources tell us that GM is now attempting to mask this sub-optimal geometry with chassis tuning rather than doing the right thing and actually fix it.

Now, class, if you were developing a BMW 3-Series competitor, how important would the issues of weight and front suspension geometry be? Very important? Sort of important? Existentially important? Meanwhile, what about AWD? How important would that be? GMI may be reminded of the Sigma’s development, but GM’s history is rife with vehicles that started with a bold, simple vision, only to be re-engineered into mediocrity. A line of driver-oriented, four-cylinder-only, rear-drive small luxury cars is an intimidating step to make… but it could have been distinct, downright unique. And it would have easily handled the CAFE issue that Lutz worried about as ATS development was beginning in earnest in 2008. Heck, BMW is putting a three-banger in its next-gen Dreier… so why was Cadillac so worried about bigger engines and AWD, while glossing over the “locked-in” sub-optimal front suspension?

Regardless of why ATS development has taken the turn that it has, the effects are already clear.

According to sources familiar with the Alpha program both internally at GM and the supplier level, GM has made several other additions to the requirement list of Alpha beyond engines. Among the additions were: a new electronics system and aerodynamic shutters (similar to the Volt).

Each addition has caused another issue to engineer around, thus causing the Alpha program to exceed GM’s mass requirements for the car by nearly 500-pounds. It is unclear how heavy Alpha products will be, but every independent Alpha source GMI has communicated with has indicated that the final curb weight could push 4,000-pounds unless GM puts the program on a mass reduction plan before launch.

So, never mind about all that “GM is focused on weight gain” praise we were lavishing around yesterday. A BMW 335ix with AWD and an autobox only weighs 3,824 lbs… if Cadillac’s ATS comes in “pushing 4,000 lbs” it won’t be a Dreier-fighter, it will be a CTS with less interior room. Which, it turns out, is actually part of the problem.

Another issue the Alpha program has been strapped with is the addition of Alpha+ about halfway through development. The Alpha+ chassis is a larger variant of Alpha, intended for use with the next-generation Cadillac CTS. Naturally, Cadillac has another list of requirements for Alpha+, including the need to accommodate twin-turbo V-6 engines. This has added another layer of complexity to the Alpha program, driving up both costs and mass.

Maybe, just maybe, GM has worked some kind of magic with this Alpha platform that will yield equally exciting Camaros, ATS’s and CTS’s… but that’s a lot of work for one platform. Compromise is almost inevitable. As I wrote on the Alpha prorgam over a year ago now,

Weight and expense problems? Trying to develop a single platform that’s capable of competitively executing every RWD application across several brands? Compromising mainstream variants in order to justify the insane engine requirements of low-volume halo versions? Does any of this sound like a new day for GM’s RWD reputation to you?

Don’t get me wrong: a sub-Zeta RWD platform is a great idea (in Cadillac’s case, probably an existentially necessary one), and my inner enthusiast thrills at the idea of both budget RWD treats and tiny, loony supersedans. But the last thing I want to see is GM spending taxpayer money developing a platform that tries to fill too many niches, only to end up a dud of a compromised-to-death mess.

But it seems that the “all things to all enthusiasts” approach has ruled Alpha platform development, and as a result, well… we’ve got signs of “not good” everywhere. GMI concludes:

Recently GMI has spoken with sources–both internal and supplier–that are working on the Alpha program. According to those sources the Alpha program has been a near constant stream of drama and problems for GM, all of which were compounded by the company’s June 2009 bankruptcy. Even today, as the program nears its final stages of development, problems are still being worked out of the Alpha cars.

GM is now struggling to reduce Alpha’s mass by a quarter-ton. One source indicated that GM is willing to throw all sorts of new composite technologies at the body, structure and powertrain to achieve that goal. Those materials are being thrown at both the Cadillac Alpha cars and the sixth-generation Camaro.

At last report the Cadillac ATS is still slated to launch in mid to late 2012 as a 2013 model-year vehicle.

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Head Games: GM Drops 13 Lbs From Its 3.6 V6 http://www.thetruthaboutcars.com/2011/05/head-games-gm-drops-13-lbs-from-its-3-6-v6/ http://www.thetruthaboutcars.com/2011/05/head-games-gm-drops-13-lbs-from-its-3-6-v6/#comments Mon, 16 May 2011 17:35:50 +0000 http://www.thetruthaboutcars.com/?p=395055 One of the most consistent and valid criticisms of GM’s product development, even in the post-Lutz era, is the class-leading weight that so many new GM products carry around with them. To a number of industry observers, the lingering weight problem that so many of GM’s cars struggle with is a sign of corners cut […]

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One of the most consistent and valid criticisms of GM’s product development, even in the post-Lutz era, is the class-leading weight that so many new GM products carry around with them. To a number of industry observers, the lingering weight problem that so many of GM’s cars struggle with is a sign of corners cut in the design process. GM’s cars may look, feel and drive better than they did five, let alone ten, years ago, but clearly the battle for truly “world class” products isn’t over.

And now we’re getting some of the first indications that GM is taking the weight issue seriously, as GreenCarCongress reports that GM’s engineers have pulled 13 lbs out of its 3.6 liter direct-injected V6 simply by redesigning its head. Given that the 3.6 is already one of GM’s better engines, and is used in a huge number of its vehicles, that’s a solid first step as The General takes on the battle of the bulge.

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Gallery: The McLaren MP4-12C Engine http://www.thetruthaboutcars.com/2010/03/gallery-the-mclaren-mp4-12c-engine/ http://www.thetruthaboutcars.com/2010/03/gallery-the-mclaren-mp4-12c-engine/#comments Thu, 18 Mar 2010 15:47:03 +0000 http://www.thetruthaboutcars.com/?p=349486 In the early days of McLaren’s MP4-12C development, it was suggested that the new mid-engine supercar would use AMG’s 6.2 liter V8. As things got awkward between Mercedes and McLaren though, a mysterious “German-built V10″ was rumored to be have replaced the AMG unit under at least one testing prototype. In the end, McLaren built […]

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In the early days of McLaren’s MP4-12C development, it was suggested that the new mid-engine supercar would use AMG’s 6.2 liter V8. As things got awkward between Mercedes and McLaren though, a mysterious “German-built V10″ was rumored to be have replaced the AMG unit under at least one testing prototype. In the end, McLaren built its own engine, the M838T. It’s a twin-turbocharged, direct-injected, 3.8 litre, 90° V8, developing about 600 horsepower at 8,500 RPM. 80 percent of its 442 lb-ft of torque is reportedly available under 2,000 RPM. Also, it looks like mechanical sex.

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