[happy1]

This engine was developed by Yamaha in Japan. I haven't seen the parts, but it is probably very similar to a 4-cylinder motorbike engine block. When assembling them you put the crank into the upper block, then after installing new bearing shells into the lower half of the crankcase, you lower that carefully onto the upper half, and you start torquing the bolts in a rotating pattern, gradually starting with a low value. Go in circles until you have the suitable torque.

Maybe have a look at the factory repair manual for a Yamaha motorbike engine. Suzuki motorbike engines are the same.

Why not try to call Burton in UK. Since they are a racing shop obviously with their own R&D team, they probably also assembles engines, and knows which torque is required for the crankcase on this one. It is worth a try.

Cheers,