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JeffBowlsby |
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914 Wiring Harnesses ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 8,548 Joined: 7-January 03 From: San Ramon CA Member No.: 104 Region Association: None ![]() ![]() |
Just read an intriguing article on CNN about iPhones and the manifestations of their carbon footprint. I don’t consider myself a tree hugger but some things in the article resonated with me.
‘The greenest iPhone is the one you already own’ Made a strong case for the right to repair movement, carbon foot print impacts and reduction, efficiency in labor/natural materials usage, protecting the environment etc, etc. One of the many things about the 914 we enjoy is that unlike many newer commodity cars (which BTW there is a shortage of) is that that we can repair/maintain them ourselves and essential parts are available. This paradigm applies to our 914s and really all things now considered vintage, old, classic, including all classic cars that still function yet remain serviceable and with many years of service life remaining if but for manageable efforts to maintain. Our current disposable consumer model may be reverting to the former ‘built to last’ model past generations relied on and promoted. Seems like the classic car hobby has been brow beaten for so long when in reality we are in the forefront of being environmentally respectful. The main thing I think of that is not as environmentally conscious about our cars is emissions. But can those be cleaned up easily enough with a bolt on cat? So Ben, will you develop an exhaust for us with a cat or two? @mb911 If you want to join this thread PLEASE stay factual and don’t turn political. Just the facts ma’am. |
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Superhawk996 |
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#2
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 5,915 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch ![]() ![]() |
The main thing I think of that is not as environmentally conscious about our cars is emissions. But can those be cleaned up easily enough with a bolt on cat? The problem is that it just isn't that simple. Is the better than nothing? Probably. But at what cost? Catalytic converteres are not cheap. They are best implemented on a basis of systems engineering vs. a slap on fix. Cat's run at very hot temperatures (up to 1600-1800F) that if not properly managed at best are going to cost you lost performance, poor emissions conversion efficiency, and at worst become a fire risk if not packaged carefully. The catalytic converter wants to the close the the heads for quick light off. Now you have a whole new cooling issue for air cooled engines. Revist the 911 2.7L six fiasco for a taste of how not to do air cooled engines with a Cat. A good portion of the reason OEM's moved toward closed loop control (using O2 sensors) of Fuel Injection systems was to better manage the catalytic converter. Modern engines have as many as 4 catalysts and 4 O2 sensors on V-engines. You would really want at least two for the horizontally opposed nature of 914's. I know a lot of people will find this hard to belive but there are times (like high load / WOT) at which the catalytic converter is running too hot and the FI system begins to dump in extra fuel just to manage the catalyst temperature and cool things down. Failure to keep it operating within the Cat design parameters results in the substrate breaking down, cracking, crumbling and eventually clogging up, resulting in backpressure that degrades the whole system or results in a non-running engine. Don't want to come off as overly negative. It's just that it isn't as easy as just slapping on a Cat and then magic happens. |
horizontally-opposed |
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#3
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 3,432 Joined: 12-May 04 From: San Francisco Member No.: 2,058 Region Association: None ![]() ![]() |
Catalytic converteres are not cheap. They are best implemented on a basis of systems engineering vs. a slap on fix. Cat's run at very hot temperatures (up to 1600-1800F) that if not properly managed at best are going to cost you lost performance, poor emissions conversion efficiency, and at worst become a fire risk if not packaged carefully. The catalytic converter wants to the close the the heads for quick light off. Now you have a whole new cooling issue for air cooled engines. Revist the 911 2.7L six fiasco for a taste of how not to do air cooled engines with a Cat. A good portion of the reason OEM's moved toward closed loop control (using O2 sensors) of Fuel Injection systems was to better manage the catalytic converter. Modern engines have as many as 4 catalysts and 4 O2 sensors on V-engines. You would really want at least two for the horizontally opposed nature of 914's. I know a lot of people will find this hard to belive but there are times (like high load / WOT) at which the catalytic converter is running too hot and the FI system begins to dump in extra fuel just to manage the catalyst temperature and cool things down. Failure to keep it operating within the Cat design parameters results in the substrate breaking down, cracking, crumbling and eventually clogging up, resulting in backpressure that degrades the whole system or results in a non-running engine. Don't want to come off as overly negative. It's just that it isn't as easy as just slapping on a Cat and then magic happens. ^ Not overly negative at all. All good points, and to the heart of things I've pondered in adding cats (even small or less restrictive ones) on a system (and car!) that wasn't designed for them. And yes on two vs one on an H4 or H6. |
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