Looking at low boost build - Input please!

[QC97Z]

Id be ok with going with a pully that would get me the 4-5psi at a higher RPM, that way i would be at less boost durning regular driving, and potentialy increasing longevity of the motor?
I like the idea of having the power there when needed, But not using it when its not.

Edit: Also, will i need to run a BOV? And I know an intercooler is a good idea, but will it be essential?
I ask because ive found these ATI kits that appear to come without fueling systems or an intercooler, and a p1sc (id link but i dont think thats allowed?)
However, at 1800 more than most used kits cost, i dont know if this would be a real bonus. Tricked out toy is selling a kit on here, but I cant tell if its overkill as well?

Your first comment sort of ties in to your question about needing a BOV, or in the S/C world, a "bypass valve".

Yes, you will need a bypass valve. It works the same way a BOV does for a turbo. If you've been boosting, and you let off the gas, you need that pressure still left in the charge pipes to be released, otherwise it will push into the motor and create a fatal lean condition. I'm using a Vortech bypass valve on my setup.
"Regular driving"....well, under "regular" or "grandma" driving, you'll always be in vacuum, and any boost you're creating will expel into the atmosphere from having a bypass valve. When you step on the gas and open the TB (depending on how much), you'll reduce vacuum, eventually to zero, then you'll start boosting. So whether you have "power" or not kind of depends on you...What I'm saying is if you have the unit pulley'd for 4-5 PSI at max RPM (6000 or so), you won't see (or feel) much unless you're really mashing the throttle. And at 4K rpm, you may get like 3 psi max. Get a smaller pulley so you can be at 5 psi at 4K rpm. Then watch your RPM from there, or get some sort of wastegate that will expel anything past 5 psi. Then you could boost earlier, and ramp up the RPM however much you want and never exceed a 5 psi target.
An intercooler would be a good idea, even for low boost. ATI has Twin High Flow kits, or you could do a smaller FMIC custom on your own. I have a huge FMIC behind my front bumper. FMIC = Front Mount InterCooler.
Yes, most ATI kits don't come with fueling. For a low boost setup like yours, a Walbro 255 in the tank, stock fuel filter and lines, a fuel pressure regulator that will reference boost 1:1, and some bigger injectors should do (48#?). No fuel rail or line mods needed. I'm still running the stock lines, stock fuel filter, and stock rails. They're good to 700+ RWHP.

[Bigbadwhitey]

Your first comment sort of ties in to your question about needing a BOV, or in the S/C world, a "bypass valve".

Yes, you will need a bypass valve. It works the same way a BOV does for a turbo. If you've been boosting, and you let off the gas, you need that pressure still left in the charge pipes to be released, otherwise it will push into the motor and create a fatal lean condition. I'm using a Vortech bypass valve on my setup.
"Regular driving"....well, under "regular" or "grandma" driving, you'll always be in vacuum, and any boost you're creating will expel into the atmosphere from having a bypass valve. When you step on the gas and open the TB (depending on how much), you'll reduce vacuum, eventually to zero, then you'll start boosting. So whether you have "power" or not kind of depends on you...What I'm saying is if you have the unit pulley'd for 4-5 PSI at max RPM (6000 or so), you won't see (or feel) much unless you're really mashing the throttle. And at 4K rpm, you may get like 3 psi max. Get a smaller pulley so you can be at 5 psi at 4K rpm. Then watch your RPM from there, or get some sort of wastegate that will expel anything past 5 psi. Then you could boost earlier, and ramp up the RPM however much you want and never exceed a 5 psi target.
An intercooler would be a good idea, even for low boost. ATI has Twin High Flow kits, or you could do a smaller FMIC custom on your own. I have a huge FMIC behind my front bumper. FMIC = Front Mount InterCooler.
Yes, most ATI kits don't come with fueling. For a low boost setup like yours, a Walbro 255 in the tank, stock fuel filter and lines, a fuel pressure regulator that will reference boost 1:1, and some bigger injectors should do (48#?). No fuel rail or line mods needed. I'm still running the stock lines, stock fuel filter, and stock rails. They're good to 700+ RWHP.

Awesome, thank you! The wastegate seems like a great idea but im confused at the difference between a bypass valve and a wastegate? A wastegate prevent there from being more than 5psi by releaseing air from the intake pipe preventing more than x ammount of pressure to build up? Where does the bypass valves it and how is it different?