Quote:
Originally Posted by autoque
I see. But then why is there a bigger difference with 3.0si engine (12HP difference) than 4.8i (5HP difference)? If Euro horses are smaller, shoudn't 4.8i have a lot more than 355 since even the 260 American horses have 272 horses in Europe? If the number is bigger, then the discrepency should also increase...:dunno:
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Good point. The direct conversion results in 350 hp = 355 hp (PS) The 3.0si at 272 hp (PS) should be 268 hp by a mathematical calculation. There are several possibilities. One is that the engines are actually different. That is possible, but not likely. It is true for the 2009 diesels, which are built to different emissions standards. The second possibility is that the tests were run a different year, according to a different test standard. There are many definitions of hp, all different. On top of the actual quantitative measure, the various tests have different rules about air intake systems, exhaust systems, and so on (since they are bench tests, not in the vehicle). SAE changed their J1349 test standard (which I used at work for years) in 2005, and some engines are rated on the old system, others on the new SAE J2723 standard. There are lots of reasons that the hp that is published for two vehicles sold in different markets won't compare directly, but remember that the engines (of a specific displacement and model) all generally come down the same production line, and only end up in a European or US vehicle based on the luck of the draw.
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