The KA24DE is a Dual overhead cam design. That means there is a separate camshaft that actuates the intake valves and the exhaust valves. The motor has 2 intake and 2 exhaust valves per cylinder. The KA24E is a single overhead cam design. It has 2 intake valves and 1 exhaust valve per cylinder. The DOHC is better in every situation unless you are trying to build a high horsepower naturally aspirated KA, but not many people do that because it costs way too much money for the power you get out of it.
I believe the SOHC has higher compression pistons. In terms of swapping, the power steering pump is on the opposite side of the DOHC, and I believe that the SOHC PS pump mounts to the head instead of the block. I may be mistaken on this though
There is a specific thread we have for newbie questions, so you may want to try there instead of starting a new thread for a little while. If you post there, no one will flame you no matter what your question is.
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