h a l f b a k e r yThe leaning tower of Piezo
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Add self service, just put your car in one end, like a car wash, and pick it up and a new VE table on the other end in 15 min... |
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There's an idea here, but I don't quite understand the author's description. (I don't think we're using the words "formulate" and "program" in the same way, for one.) If you get the description, dear reader, would you please translate? |
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Who is programming what when how? |
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Some help explaining: Modern cars have Electronic Fuel Injection, and there is a table in the computer controller that tells how much fuel to deliver for each speed and load range of the engine. If you change the engine's needs (ex/ hop up, or change to e-85 fuel)) you need to change the table. Equivalent to re-jetting a carburetor, for those who remember carburetors. |
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//Modern cars have Electronic Fuel Injection// Damn, my car just injects the old-fashioned organic fuel, not this new-fangled electronic stuff. |
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I think he's referring to aftermarket chips, though I had assumed they already come with a table of values based on engine, fuel & bodystyle/weight |
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While I like the idea, alas, I think there are precious few who have the time or inclination to learn all the details of Engine Management. The tiny portion of consumers who could make use of this "profile" couldn't ever provide the place enough business. |
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//While I like the idea, alas, I think there are precious few who have the time or inclination to learn all the details of Engine Management.// |
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Umm... Dont you guys have mechanics up there on your side of the world? Even without them, engines rely on a combination of reasonably simple chemistry and complex physics, so even if you're not a gear head its not that much of s stretch to learn. |
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//have mechanics//
No mechanics , just the dealers, and wal-mart lube, and a couple bolt-stripping, cons with shops any more. |
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//reasonably simple chemistry and complex physics// |
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Not so many gear heads with EE, Physics, and Chemistry backgrounds. |
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I love the idea. Getting a complete mapping in under an hour would be fabulous. Sadly you will need at least one warmup cycle and any number of cold and warm starts to get things ironed out. Even a good shop could be beat by an automated system. |
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The idea isn't a bad one, but unfortunately if it could be done, then a lot of the people I was working with last year at Cummins would be out of work now! |
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Also, instrumenting the car up for the dyno to be able to tell what's actually happening would take a while. Also, how do you know what limits you're working within... cylinder pressure, exhaust temp, etc. |
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Building up a model of an engine in a computer in order to optimise it takes 10s to 100s of hours of running before the model predictions are good enough. |
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Basically, good idea, but not practical, unless you're not bothered how long the engine lasts or how much fuel it uses! |
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Really? Most conventional engines operate at a pretty narrow range of conditions. What if instead of producing an aftermarket program the dyno simply came up with a base ignition and fuel map and correction maps. Let me lay it out |
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1) Car roles into the dyno room onto the rollers |
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2) An external temp regulated coolant source is hooked in. |
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3) All the efi connections are pulled and connected to an external pgmfi. |
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4) Individual cylinder knock control sensors are attached |
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5) Wide band exhaust temperature and mixture systems are installed |
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6) We dyno tune the engine controlling the inputs (coolant temp and air temp) with the external sources (chilled and heated air and coolant) optimizing output and fuel economy. |
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7) Maps are printed, then translated into whatever PGMFI or flashed onto a chip, the system could even compare the optimum settings with the output of the ECU in response to the same inputs giving a gauge of the program efficiency. You could even have a CARB legal program that grantees the final emissions will meet the emissions requirements (we have all the data now). |
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Since posting this, I have been exposed to some outstanding tuners. I am convinced more than ever that this would be feesable. Turns out almost all factory tunes are lowest common denominator. Any decent tuner can up the efficiency of the factory tune while increasing perfomance. I need some money for a chassis dyno! |
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