Fuel Pressure Regulator Questions?
 

Anyone here have a Fuel Pressure Regulator installed? If so...
What is the stock pressure and what are you runing the reg. at? What does the stock fuel pump run?
What do our stock injectors flow?
Notice any perf. difference? Smoother acceleration?
Any feedback welcome....

are you talking about aftermarket replacement regulaters??


from monster pro 5 with 440HP

Yes...I hear mixed opinions on the pro's and con's of an aftermarket Fuel Pressure Regulator...I thought someone on this board had the Ractive one installed?
Just want to know if it's worth it..

i have a turbo charged application withthe stock regulator
for boost i use a BEGI rising rate regulator in line with the stock reg for fuel enrichment
the stock reg is good enough because no matter what you do the computer will take the extra fuel away trying to keep the A/F ratio at 14.7 :1
what is the year make and model of the vehicle

Oh. I see...my car is 02 P5, I guess upping the pressure with a regulator will just be overiden by the stock ecu then? I just thought that maybe with a CAI and exhaust the engine may be a little Lean...
So no benefit then?

no the ecu will change injetor duty cycle to yake away the extra fuel it sees
if you plan on doing any upgrades and want to see any improvements you will need a voltage clamp on the O2 sensor to give a false signal to the ecu
that will allow extra fuel pressure
with your cai and exhuast you might se 10-15 hp max
untill you turbo charge that is!
call FLYIN MIATA they have the voltage clamp for forced induction maybe you can work something out with them
later

Thanks for the help!

From what I have read on here, or cars run very rich. If anything(without a turbo), you would want to lean the mixture a bit to try a squeeze a few more ponies out, not try and richen it with added fuel pressure. Correct me if I'm wrong.

the majority of the cars out there run on the rich side to compensate for variables the computer cant always control
like the type of fuel your going to use
but on the 2002 mazda and ford pcm's they are very intelligent
they WILL maintain a 14.7:1 ratio
when turbo chargered the intial acceleration when load allows boost to overtake atmos. pressure there is a possibility for a lean spot until the ecu catches up
even so the ecu only wants a 14.7 ratio
your goal would be 11.5 - 12.5 :1
rising rate reg will help maintain that as boost increases so will fuel pressure
the mazda ecu has the ability to take away (STOCK) 30 %of the fuel to correct the fuel ratio
it also has the ability to ADD 25 % but rarley and only over 4500 at WOT
later from monster pro 5

Wouldnt a FPR be beneficial in open loop though. Just in closed loop it wouldnt be beneficial.

a RISING RATE REGULATOR in open loop yes
but what i am saying is that open loop isnt kicking in till 4500

there are ways for the regulator to be beneficial while in closed loop
one way would be to controll what the info the ecu is recieving from the O2 sensor
otherwise if you were to just upgrade regulators for performance you will most likely never see the benefits untill you are revving high
if your motor is stock i wouldnt recomend to much of that

later
from monster pro 5