can anyone help i am having the 2.0ltr engine in my impreza replaced with the 2.5 lump ive most parts etc the engines out and i have the heads split from the block. How ever i have been told i should have the heads modified to match with the block ??? , ive checked and they seem an exact match the part i was told should be modified is where the heads meet the combustion chamber any advise???


Thanks

Tam

 

the bore of the chamber is different.. you can either take the sharpe edge off or get them machined or ported out but chamber modification is something that really should be left to the experts.. removing the sharpe edge should be fine for you to do yourself. ie. they will bolt on and run no problem but the chamber doesn't match the bore.. and the sharpe edge of the head chamber now exposed due to the larger bore will cause hot spots and less tollerant to timing, and also possibly cause extra stress on the head gaskets.

Simon