Take a good long time to do your research and ground works on your project. Go ask the shops, ask owners of such system, search for modded myvi clubs and have a good fundamental understanding on the system and components. Or else, you'll get into trouble very easily.

Don't just rely merely on the mechanic you work with, you must have real understanding and what you want realistically. Or else, you'll just create misunderstanding between you and the mechanic and the mechanic will just make up assumptions on things you can't clearly convey. This is where the blame game starts.

Component wise, you'll be spoiled by choices depending on your budget. But please take note on some really crucial but often neglected issue, sealing. That means at least a good aftermarket gasket and new bolts to screw the top and block together. Next is cooling. You must budget in these or else you're likely to end up burning money.

This post has been edited by wkc5657: Oct 27 2017, 10:10 AM

I'm not aware of it as i don't own myvi, you could search/ask around at the myvi owner club :
https://forum.lowyat.net/topic/3162680