i will tell ya a secret, the n/a motor is identical to the turbo with the exception being the pistons (higher compression) and the oil and water bungs are not drilled and tapped.
the rods are the same ,under piston oil squirters are the same, all other differences lie in the computer and external componants.. and the na with a turbo makes more power per psi of boost than the B6T (9.4-1 compression) spools the turbo faster, and has more out of boost torque..
that being said, an xr2 with a na motor for the right price, may be worth your while...it can be made back into a B6-t and make more power than the original motor with the same setup... and if you already have the xr2 chassis ...you get the idea ..well be good and have fun ..Joe