Boost
 

at what psi of boost must you upgrade the fuel system? and when you upgrade it what would you need and about how much would it cost?

to my knowledge if you have dp, mp and catback and fcd you've reached about the limits on how much the stock pump can flow and you should be pushing around 10 psi. honest why would anyone want to tax their fuel system to its max. cause all you have to do is drive it really hard on a cold winters night....you know the rest. there are 2 upgrade pumps walbro and RP one. I've got the walbro. both are easy to install.