Piston & Head Matching

[AESamaan]

I have a freshened E21 323i head. I also have a freshened e30 Super Eta block.

I have heard that the chambers have to match the piston tops. Is this an appropriate match? If not, why and what are the consequences?

[digger]

the SETA pistons are like m20b25 pistons but a little smaller dome that will only suit the 885 head from a m20b25 or the SETA. it causes inference on 200 and 731 castings

that head needs a flat top piston from a regular ETA.

you need a different head to put onto the SETA short block