ramrod Why not use a non turbo engine instead? Then add the turbo onto it
This.
Because old turbo engines do have increased bore wear.
You don't really need sodium-filled exhaust valves to make a strong and reliable turbo engine.
Building up an 'L' block NA B230 from a late 240 / 940 is going to be a better, more reliable starting point - it will have less bore wear, 13mm rods, the higher volume oil pump, and either be pre-drilled for squirters or have them fitted.
Fitting a B23-anything into a post-1986 car is going to be a hassle legally.
