For a Turbo 6 engine - use the pre-81 AMC 6 - as this is the HD unit : Stronger cyl. block Stronger main bearing caps Use a '75 AMC open chamber stud rocker arm cyl. head . Use the complete EFI system from an '85 - '90 Cherokee - called a 'Renix' EFI System - as it is flexible enough to handle Turbo Charging or normally aspirated Performance cam changes. Get full U shapes and straights from : www.burnsstainless.com - get the thickwall tube - use a carbide blade on a chop-saw & tack weld together - take to a welder to finish. Get an '87 Buick Grand National Turbo unit - used or rebuilt : check www.jyturbo@xxxxxxxxxxxxxxx for one . You can run up to 8 lbs boost without an Intercooler . After 10 lbs. I would consider installing Forged Pistons . I have a complete Renix EFI system - boxed & ready to ship should you be interested in building a Turbo Car . Brien. NEW YORK