fpr tuning

[mr2gons14]

ok so maybe ive been working to much idk but i feel retarded cause i dont remember how the hell to tune my circuit sport fpr someone gimme a hand i looked around couldnt find nothing. So let the hating begin haha please be gentle

[801nismo104]

u dont tune a fuel pressure regulator. you just set it to a certain psi. i have mine set at like 37 psi at idle with vacuum on my sr20

[mr2gons14]

thats what i mean lol i do that with the car off if i remember correctly lol but how i know how to adjust but the gauge reads 0 when i turn the car to on

[ultimateirving]

Mrgons, i will help.
Start the car, get it to normal operating temperature.
Once warmed up WITH the car running, Disconnect the vacuum source to the FPR, but make sure the vac tube is plugged( Idle will fluctuate if its open). Adj the FPR by turning the adjustment screw until you reach ~43psi. reconnected vacuum tube, and psi should drop to ~36ish

[mr2gons14]

thanks bro always there to save me when im retarded lol btw back in az on the 23rd of dec ill hit u up sometime

[iRONDONkey]

is a FPR a necessity?

i got mine for free. not sure if i should use it.

[Mikester]

Originally Posted by iRONDONkey

is a FPR a necessity?

i got mine for free. not sure if i should use it.

Save it for when/if your current one craps on ya... Not a necessity- Plenty of 350-400hp SR20's running on stock regulators. It becomes a necessity beyond that, or when the person tuning your car says you need an adjustable; whichever comes first (usually the latter).

[Croustibat]

Originally Posted by iRONDONkey

is a FPR a necessity?

i got mine for free. not sure if i should use it.

If it aint broken dont fix it, mechanics 101.

Originally Posted by Kingtal0n

The factory fpr will support about 300rwhp in a 240sx... anymore than that is asking for trouble. It will not support 400rwhp usually.

Strangely it only happens in the US. Everywhere in Europe, where CA18DET and SR20DET come as standard in S13 / 14 , we dont have that problem.

Even stranger, it seems to only happen to zilvian posters. Maybe because some fellows keep repeating that kind of BS when they actually dont have a clue ?

[EDacIouSX]

Originally Posted by Croustibat

If it aint broken dont fix it, mechanics 101.



Strangely it only happens in the US. Everywhere in Europe, where CA18DET and SR20DET come as standard in S13 / 14 , we dont have that problem.

Even stranger, it seems to only happen to zilvian posters. Maybe because some fellows keep repeating that kind of BS when they actually dont have a clue ?

I have no clue but maybe the US KA24DE FPR is not as good as the SR FPR? They could be the same though...

[Croustibat]

Originally Posted by EDacIouSX

I have no clue but maybe the US KA24DE FPR is not as good as the SR FPR? They could be the same though...

I was talking about the stock SR20 and CA18 FPR which suddenly go bad when crossing borders according to this forum.

[Kingtal0n]

Originally Posted by Croustibat

I was talking about the stock SR20 and CA18 FPR which suddenly go bad when crossing borders according to this forum.

I literally just tried to tune an S13 sr20det, and the OEM regulator gave up exactly around 330rwhp. The brand new Tomei 740cc injectors were open 95% duty cycle and it barely supported 330rwhp, air fuel was dropping to 15:1 by 7,200 rpm. Must be the air, yeah thats it, USA air causes it.

[mr2gons14]

lol depends on mods ur running stock worked fine for me till recently

[801nismo104]

If the gauge reads zero with the car on then maybe its broken or you have your fuel lines backwards on the fpr

[mr2gons14]

lol the car wasnt turned on the ignition was just turned to the on position shouldnt that kick the gauge on? the lines may be backward actually havent checked that

[ultimateirving]

The gauge only reads presurre with the car running.
The gauge will move when the fuel pump primes, but mine goes back to zero after its done priming, with the engine off.

[mr2gons14]

thats prolly it lol imma try it ur way tomorrow mornin

[Kingtal0n]

The factory fpr will support about 300rwhp in a 240sx... anymore than that is asking for trouble. It will not support 400rwhp usually.

[Nizzan4u2nv]

FPR goes on the return line from the fuel rail. So fuel rail to fpr then fpr to return line. Use the same vac source as the stock fpr. Fuel filter is on the feed line from tank so you dont mix them up. Prime it before starting it and get it in a reasonable range before starting the car. If its 0psi after priming then something isnt right.

[Croustibat]

I wonder how all the people i know with 400+ SR20 S14 are doing then. Must be doing some kind of voodoo

[omgRWDgoodness!]

[Kingtal0n]

Originally Posted by Croustibat

I wonder how all the people i know with 400+ SR20 S14 are doing then. Must be doing some kind of voodoo

I said I tried to tune an S13, not an S14. the S14's are newer and there is a chance that the regulators are higher quality and/or different design or simply less wear and that is why they sometimes work fine.

Nevertheless, not a part I would fail to replace on a 400 horsepower car, given the low cost and importance of.

[mr2gons14]

yea that does sound a BIT off