Quote:
Originally Posted by Nickshu
Still don't understand your statement...
An 82ROW has higher compression pistons than a 82US. 9.8 vs 9.3
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In 1980, much like 1975 and every succesive year after, the CAFE and emission standards where rising quickly in US. In order to meet those standards for MY 1980 and avoid gas gussler tax in US, Porsche raised compression ratio and increased port velocity at lower engine speeds by making the intake ports and runners smaller. There was also the change in ignition curve and the addition of the O2 sensor with a lean fuel curve. All of this was done to improve fuel economy and lower emission while maintaining performance at the lower speed limits in the US. The changes effectively created higher cylinder pressure at lower engine speeds creating a very responsive engine with a nice flat torque curve at lower engine speeds. This was a common formula for a lot of manufacturers selling cars in the US (ever heard of BMW's ETA engines?).
In Europe (and everywhere else) the standards were different as well has speed limits in some areas so they had more free reign to build and tune to those conditions.
Even with lower compression than the US version, the '80 RoW engine with bigger ports, advanced cam timing, richer fuel curve, and more ignition timing still generates more torque than the '80 US. It's also a livelier engine at higher revs that will respond better to mods (ie SSI's). The downside is that it gets noticeably worse fuel economy and pollutes.
Back to the OP, a US 9.3:1 CR engine with a RoW CIS and distrubuter (or recurved stock dizzy) would make for a great engine, much like the 930/10 204 hp engine. However, to make it work, you have to modify the stock heads or use heads that already have the big ports.