ok guys some good info here

I think i would like to opt for this option, have the car set up to run 2 differnt boosts ie hi and low.

on the low boost i would like the ke fueling set up for this all the time say 14psi im hoping that this means i could get away with near on std fueling just tweeked alittle to save fuel.

Then have hi boost say 17psi which is activated by boost activated switch at 15psi and use the cold start valve for this

How much extra fueling can you get out of the cold start valve somone mentiond %5-7 how much psi would this equate too?

In an ideal world id like the boost to be set as hi as std fueling can fuel ie 12 psi without raising fuel pressure so fuel econamy is good then have a cold start valve that fuels for extra 5psi when needed is this possible by running a bigger injector in my coldstart valve?

Thanks Paul.