[HondaDustR]

Usually swapping a good used head with straight valves is all you need to do to fix your problem, but the 83 motor should drop in without any problems. People are parting cars out in the pelican classifieds all the time. Unless your current motor is known to be wasted, it's better to just fix it rather than buy someone else's potential problems, as well as all the little minor details getting an early block hooked up to a late car.

Not sure about the power differences. I have seen some sources say the higher compression motors were introduced in 87, but most everything else says they were in 88 only. All of the motors before 88 had the same 9.5:1 compression ratio piston design in the US and had generally the same specs, but I have seen minor differences in reported power for various models and years. The 10 hp was from the 10.2:1 pistons used in 88 (again, I saw one list saying they were made in 87, too). The only other significant difference is the change to a slightly more aggressive camshaft profile in 85 (IIRC). The cams are all interchangeable between 8v motors and a late cam can be installed on an early motor for a slight boost. The steel tube exhaust headers in 87-88 were supposed to flow better than the standard cast headers, but the early versions (of the steel) were very prone to cracking. The updated design added an expansion section in the 1-4 header section. The Y-pipe connecting the headers changed slightly between early and late, with the secondary tubes being about 2 inches longer on the late part (maybe better tuning for the late cam profile). I have also seen pictures of a different intake port design with little "tabs" sticking out into the fuel injector path, but they must have been only a limited run, as most 8v heads have smooth ports. I don't know what kind of power gain there was from going to the smooth ports. Just for information does anyone know of the tabbed intake port heads I saw and what year(s) they were from? All of these little differences may account for the various specs of 145, 147, 153, 155 hp at either 5500 or 5800 rpm that I have seen. The 88 motor is 163-165hp at 5800 rpm. The nice plus to the 83 motor is they used sinter forged rods.