whats the most boost u can run on pump gas

[LBSVT93]

whats the safest boost level to run on pump gas with a whipple or KB, and whats the most safe timing level? Whipples site says a 3.00 pulley will make 17 psi, and a 2.75 pulley will make 19 psi....just wondering, also what should plugs be gapped at with the whipple looking into ngk's

 

[lloyyd]

17 lbs on pump gas, 19*-20* max timing. I run NGK TR6's gapped at .032.