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Marcus
11-22-2000, 12:36 PM
If i export a German spec M3 the US will i have any problems registering the car in the US?

RyanM
11-22-2000, 01:20 PM
The Euro spec M3's has the converter farther down the exhaust for and the US M3 had it moved up a bit for emmissions reasons (so I read).<p>

loki
11-22-2000, 01:22 PM
But it's not. You will be faced with DOT, EPA and Customs, not to mention the good 'ol DMV. <p>trust me, I've imported cars before....<p>However, if you can do it sneakily by disassembling the engine and transmission from the car and shipping all 3 units over *individually* for reassembly in the US, if you have that much free time on your hands.<p>:::grin:::<p><i><br>If i export a German spec M3 the US will i have any problems registering the car in the US?<p></i><br>

Brian S
11-22-2000, 09:56 PM
Why does everyone think it's so difficult to import an E46 M3? It's not like the E36 EVO...this time around the M3s are identical except for the stupid exhaust system and speedo (km/h=>mph). If it was soooo difficult to import cars, why is there such a huge market for Euro Ferraris (and they require a lot more work than the M3)?

Dilster
11-23-2000, 04:46 AM
<i><br>The Euro spec M3's has the converter farther down the exhaust for and the US M3 had it moved up a bit for emmissions reasons (so I read).<p></i><br>Nearly M, the C converters on the US spec are further from the engine due to US regs on heat build up in the convs. caused by the engine, hence the loss of 10bhp.<br>Dilster

Mr. Grinch
11-23-2000, 05:26 AM
Articles I've read put them closer, because US emissions are more strict on start-up emissions, and that requires getting the cat hotter, quicker. You do this by moving it closer to the header. The further you are from the header, the cooler you get, and the less effective the cat is at changing unburned hydrocarbons into CO2 and H2O. <p>This is a change for emissions we're talking about, not some heat safety reg. Catalytic converters require heat to function properly, and in this case, the CA rules are sticky on startup emissions, so they decided to warm the cat's up quicker by moving them closer. <p>Also on a tuned exhaust system such as this, obstructions in the line have more effective back pressure the closer they are to the heads, for at least two reasons. <p>1) Gases are hotter at the heads than at the tail pipe, therefore the volume of gas is greater at the heads, diminishing as it cools on it's path to the tail pipe. The closer you are to the head, the higher average flow you have (by volume, not mass). <p>2) Even if you had a system where exhaust where a constant temp, from heads to tail pipe, the effect of an obstruction is still greater the closer you are to the heads. While average flow through the system is constant, the instantaneous flow on the exhaust cycle is much greater at the heads than at the tail pipe. This is because the exhaust is smoothing the flow of the gas, from a series of distinct explosions to a series of less distinct smoother pulses. <p><br>

Dilster
11-23-2000, 10:19 AM
Sorry I was completely wrong having gone back to my sources I obviously didn't understand what "upstream in the exhaust" means, but I do now.<br>Thanks<br>Dilster

Dilster
11-23-2000, 10:21 AM
Sorry I was completely wrong having gone back to my sources I obviously don't understand what "upstream in the exhaust means".<br>Dilster

Mr. Grinch
11-23-2000, 04:57 PM
Now what we need is a way to figure out how to remove the cats and everything back. With the two lambda sensors in the headers, I wonder if they bothered to put any sensors in the cats.<p>

Randy G
11-24-2000, 03:53 AM
<i><br>Articles I've read put them closer, because US emissions are more strict on start-up emissions, and that requires getting the cat hotter, quicker. You do this by moving it closer to the header. The further you are from the header, the cooler you get, and the less effective the cat is at changing unburned hydrocarbons into CO2 and H2O. <br></i><p>It seems a shame to lose performance just to get the cat to light off a few minutes quicker. I wonder if they could accomplish the same thing with an electric heating element to help jump-start the catalytic converter. I have no idea if this would actually work. Anybody know more about this stuff?

Mr. Grinch
11-24-2000, 04:42 PM
That's not a bad idea at all. Certainly would be superior to mechanical methods as it would be more reliable not having moving parts. However, I fear the size of heating elements would be too big to come close to the heat of hot exhaust gasses. Would be nice to know what kind of time / temperature difference we are talking about!<p>Or perhaps BMW can figure out a way to reduce the percent unburned hydrocarbons before they ever get that far... but this would require _major_ engine changes, some being counter-productive to the M engine design goals. <p>Personally, I think the whole emissions testing industry is a little out of wack. It does not account for lower mileage that results from emissions equipment, resulting in more gasoline burned. While it measures hydrocarbon output, it does not put limits on sulfides or ozone or other byproducts of the emissions systems, which are just as harmful to the environment from my point of view. <p>We pay, in more ways than one, to meet these faulty emissions requirements, while we send our kids to school on buses that would fail to meet any emissions or safety spec. I guess this is supposed to teach them about polition control and safety, or a lack of it?<p><br>


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