$500 to $5000+ for a Volvo Turbo 4 cylinder conversion, depending on whether you buy a well used drivetrain and install it yourself as it is, or whether you rebuild it before you install it, or whether you buy a low mileage late model (93-95 940T drivetrain in the US) and have it installed as is, or whether you have that rebuilt before it is installed.

Probably the same price for a 6 cylinder, should you want one, depending on its age and condition and what you do to it and who does the work.

Probably $3000 to $10,000+ for a 6 cylinder twin turbo, depending on its age and condition and what you do to it and who does the work.

I think Ross Converse is charging about $7000 for a new Ford 5.0 HO V8 conversion, though people have done it for half that with low mileage used parts when they do the labor themselves. Some have done it for even less.

Philip Bradley