What is stock and the maximum limit of fuel pressure on a 3.1?

How many bolt ons can the stock fuel pressure settings handle?

 

On the pump? Dead head pressure (max) is 60 psi. To check your pump, crimp the return hose shut and turn your key from "off" to "on".

On the regulator? Beats the hell outta me To check this, you need to drive with the fuel pressure gauge connected; at a stop light, go WOT and the gauge will show the regulator's max pressure. (At anything other than WOT, the fuel pressure's changed at the regulator because of it's vacuum line)

 

What is stock fuel pressure on a 3.1?

 

~43

 

Now,lets say a high flow intake and exhaust were bolted on.Whats the new fuel pressure?
How many simple bolt ons before a fuel regulator is needed?

 

FP stills stays ~43

After exhaust and intake, I'd bump it up to 45-47psi, but that's just me

 

I thought the ECU adjusts the FP for the extra flow?

How can I do this on a 3.1?

 

Nope, the ECU can cut back the fuel a little, in response to it being a little rich - but @ WOT, you'll want that little bit of richness (the ecu uses a map, and doesn't adjust @ WOT)

 

I am curious to know at what point we can swap to bigger injectors and reduce the pressure. Is there a comparison flow chart availiable.

Example: say the 15lb injectors @ 47 psi would be equal to 19lb injectors at 38psi- again, just an example- not accurate statics here!

 

How can i adjust the FP on a 3.1?

 

That's why you run at WOT while watching the fuel pressure gauge, it tells you what you've got the regulator set to.

You'll need an adjustable fuel pressure regulator and a fuel pressure gauge. The AFPR for V8s will work on our V6's; I think Crane sold the cheapest one, but it re-used the stock diaphragm. While you're in there, you might as well replace the old diaphragm too.

 

With a high flow intake and exhaust

What can I set it too? 45 PSI or more?