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new fpr question...

887 views 7 replies 3 participants last post by  92nx2k 
#1 ·
ok guys im really confused. there are 2 regulators on the ve, one IN and one for fuel OUT. the one for fuel IN is the one on the passenger side of the motor, as i understand it, since this is the one that comes off of the filter. so this is the one you need to hook up the fuel pressure gauge up to...correct? well i hooked up an inline gauge and started the car with the vacuum disconnected. it read 50 psi. i pligged vacuum back up, fuel pressure did not change. i unhooked the vacuum for the fuel OUT and the fp went up to 55. i thought...what the hell does that mean. also when revving, with vacuum hooked up on both regulators, the fp does not go up as you rev. which seems wrong. we checked it on my friends stock se-r with the same gauge. his read 44 disconnected and 37 connected, and his fp went up as he revved.

so im confused about 2 things. first, which fpr do i replace when i put my nismo one on? cause the fpr for the IN line doesnt seem to be doing anything. leads me to belive i need to replace the OUT fpr, which makes no sense to me. and next, is something wrong with my stock regulator(s) if when i rev the fp doesnt move? i do have JWT computer and thats the only fuel mod. any info on this would be helpful thanks

aaron
 
#2 ·
92nx2k said:
ok guys im really confused. there are 2 regulators on the ve, one IN and one for fuel OUT. the one for fuel IN is the one on the passenger side of the motor, as i understand it, since this is the one that comes off of the filter. so this is the one you need to hook up the fuel pressure gauge up to...correct? well i hooked up an inline gauge and started the car with the vacuum disconnected. it read 50 psi. i pligged vacuum back up, fuel pressure did not change. i unhooked the vacuum for the fuel OUT and the fp went up to 55. i thought...what the hell does that mean. also when revving, with vacuum hooked up on both regulators, the fp does not go up as you rev. which seems wrong. we checked it on my friends stock se-r with the same gauge. his read 44 disconnected and 37 connected, and his fp went up as he revved.

so im confused about 2 things. first, which fpr do i replace when i put my nismo one on? cause the fpr for the IN line doesnt seem to be doing anything. leads me to belive i need to replace the OUT fpr, which makes no sense to me. and next, is something wrong with my stock regulator(s) if when i rev the fp doesnt move? i do have JWT computer and thats the only fuel mod. any info on this would be helpful thanks

aaron

The closes one to the TB is the FPR. The other is a fuel dampener.
Change the one on the drivers side.
 
#3 ·
ok thanks...did not know that. now...should the fp go up when i rev though? and also that means the regulaator on the VE COMES after the fuel has already gone through the rail, as opposed to the de which regulates it before? this is real weird. what does the fuel dampener do? and why am i at 50 psi? lol. isnt that quite rich?
 
#4 ·
This is what I got from an earlier post from bigtom:
the pulse damper keeps a steadier flow of fuel by absorbing shock in the fuel line from when the injectors cycle. this is kinda handy dont remove it. it helps the injector have a better chance of seeing the pressure intended.

Is that 50 psi with the hose connected or disconnected?
 
#5 ·
50 with vacuum connected, 55 disconnected. what do you think?
 
#8 ·
i do have jwt. it does NOT go up when i rev the engine. i have a walbro 255 pump but that only increases volume and that shouldnt have anything to do with it. it is not 44 disconnected, its 50.
 
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