I own a 1990 240sx se with the sohc engine. Could it be possible to put the head off a 93-94 doch 240sx? The lower half of the engine is the same right? Also, if I can change the heads, will I need anything else like the computer off the same car?
I'm not sure, but I would thnk that with the high compression our cars have, you may need the pistons from a DOHC model too. The piston heads may have little notches for the valves to clear. I'm not sure though. You will need the intake manifold, and all it's accesories. I believe the PCV system is a little different too. And you will need the exhaust manifold. There could be chance that the computer may not be a direct replacement. I'm not sure they use the same harness configuration.
I'd say a more cost effective choice might be to trade in your car for a DOHC model. It would save time, headahes, money...etc. Or put the extra money into more power adders!
Another thing! I'm not sure the timing chain gear in the lower half would be the same
No, the lower half's are actually different. The oil pump and distributor locations are different. I'm sure there are alot of other differences that I'm not aware of also.
Kris -- 1990 240SX