[gerhard]

Ok...

To give you proper feed back I need a little information.

If you have an H22A4, that should be the engine from a BASE Model Prelude.

I thought there was a different designation for the SH type block... which is made to bolt up the the ATTS unit.

The BASE Model H22A4 97-01 Prelude ECU is a P5M, not a P5P so far as I'm aware.

The P5M will have a connector that goes to the auto tranmission on it. The problem is, if you are not using the SS Auto transmission from a 97-01 Prelude, then you're going to have to us the ECU from 92 Prelude.

The H22A and the H22A4 series engines differ PRIMARILY in that:

- The H22A is an OBD-I engine
- The H22A is a closed deck motor (better for boosting)
- The H22A4 is a open deck motor (lowers NOx emissions)

In order to make the H22A4 an OBD-I motor, all you need to is swap the distributor and I think the CPS (crank position sensor).

Either way, when you put an H22A in a 97-01 Prelude, you need to transfer over the intake manifold, the exhaust head, the distributor, and the oil pump assembly.

So it's probably the reverse if you are putting an H22A4 in an earlier model prelude.

I put a JDM H22A motor into my 98 Prelude without issue and kept it OBD-II... so the reverse will probably work perfectly if you use the H22A ECU from a 92.

Gerhard