How strong is the U-20??

[Dan Neuman <dneuman@stars.sfsu.edu>]

Hello All,
        I have a book on metal working  and it shows a header for a bob 
sharp racing datsun that put out like 375 HP.  It was a four cylinder header
I think.. maybe a roadster maybe not?? But this got me wondering... Just how
overdesigned are the U-20??  Or are they??  Coudl they take the stress of a 
medium-low boost (~7-10psi) turbo-supercharger with out blowing itself to 
bits???  I know that some Japenese motorcycle engiens can handle twice 
the factory horsepower.. What about are cars??
        Just curious
                Daniel 69 2000
                SF CA