Fuel pressure regulator

[Jezza-7]

Is it worth buying an adjustable fuel pressure regulator?
I see that FSE are ment to be good but is it a waste of money?

Does anyone use them?

[hayesey]

don't see the point on a g40, the ECU needs the fuel pressure to be regulated as it expects or it'll not be able to control fuelling properly.  I've seen one used on a dodgy eaton conversion as a method of forcing more fuel in to cope with the extra power.  But it's pikey as hell! a proper remap is required for stuff like that.

You could also use it in conjunction with a remap to get more fuel through smaller injectors without switching to bigger ones. 

[newt]

not much point, unless you are having mapping wok done
they are adjustable yes but are not smooth/progesive
i used an adjustable and boost sensative fuel pres reg on my 20v rallye but it was on mbe management and i could map it so it was brilliant
i used it on a big power r5 turbo when i used to do dyno/mapping work , to get more fuel accross the whole range
and it worked well,
i cant really see it being usefull on a g40, only benefit would be if used in conjuction with a specific injector size and mapping session,say for example to use an injector slightly smaller than g60 (to enable fine tuning at idle as g60 injectors are a little hard to map at idle) and run a slightly higher fuel pressure,
people have probably been "recomended" to use one if you had a power run and it was starting to lean off further upthe rev range, where really you need a bigger /new fuel pump to keep up with demand or fuel pump is on the way out, or the car needs mapping
maybe worth trying one, with a guage! and setting it to factory pressure 3bar??? maybe
also running wide band and then monitoring afr whilst turning it up say0.2 bar increments.....