does anyone know the code for the 4.0 bar fuel press regulator?
is it 0280 160 575(bosch)??????

Bosch part. no.
0280 160 575 - 4 bar
B280 550 113 - 5 bar
Both are for fuel rail mounting. Not 100% sure on the numbers, but almost..

for the 20vt,right?
the oe fuel press regulator,whats its code?
do you know?
thanks
chris

The standard 20VT regulator is set for 3 bar, so those two are not OE items. But should be same fitting for mounting on the fuel rail.
Don't know what the part. no. is for the OE regulator.

Why do you want a 4.0bar pressure regulator? If this is for a standardish 20VT you could massively overfuel your engine.

and also if your going to be running more than 1 bar of boost, your at risk of ruining your injectors as the limit for them is about 5 bar pressure

i ve been told that i need one.
i have the gt 28rs,pace fmic,2,7 decat,walbro 255,str.induction pipe,gtec ii,and i am going to run 1,3 bar with cosmos prv.
so i ve been told that i need a 4.0 bar fuel press regulator.
whats your opinion guys???????
any opinions much appreciated.

dont need it, can stick with your standard one as it will flow enough fuel you need.

can i run 1,3 with the mods i have?
or whats the best boost i can run with the mods i have???(better question)

There's nothing stopping you running higher boost, as long as you've checked the car for fuelling first.

I run a very similar setup (GT28R, ProAlloy FMIC, GTec2, Ramair filter, 2.5" downpipe & decat, 255 Walbro) and I run between 1.3 and 1.5 bar depending on what mood I'm in.

the main difference between the two of us is ambient temperature - its about 2 degrees today

Don't need it, the GtechII was based upon the standard fuel pressure regulator.
you might actually lose power fitting an uprated regulator.

Joe

ok guys,i am with you,i wont fit it.
but i was told that the car responses better to acceleration....

i run a 3.8 bar regulator.

whether you need one or not depends entirely on your fuelling.

uprating the fuel pressure in the fuel rail is only really for mapped cars that can have an increased injector cycle.

running one with a plug and play chip wont do anything, the rail will have more pressure but the injectors are still working at the same rate.

so your only benefit would be in the situation that if your car was running lean at high RPM, due to not enough pressure at the fuel rail to fuel for your boost level at high RPM.

thats what i ve heard
so,i am going to fit in an a/f meter and check the fuelling,so if needed then sort out a 4.0 bar regulator?
did you read my mods above???
whats your opinion????

thanks
chris

no, AF meters are useless.

you need a proper fuelling check on a rolling road, and make sure you get a print out analysis of it.

personally id say you need to be unichip'ed and mapped. you are the higher stage of tuning, and mapping would be very beneficial.

yeah rog,i agree but i am from greece!!!!!!!!!
who would do that?????
lets supose i buy the unichip from the group buy,
who is going to map it for me here in greece??????
NO ONE.

Don't they use the SMT-6 boxes in Greece?

Joe

A couple of other points on the 4 bar reg.

It does improve the fuel atomisation (which gives the improved throttle response), but as Begbie says the spray pattern on the injectors can get unpredictable, so the higher the fuel reg the less boost you can safely run paradoxically.

The OE fuel pump probably cannot fuel 1.4 bar with a 3.8 bar reg on any coupe, you will get pressure drops in the rail which is pretty dangerous. You must use an uprated fuel pump no matter what IMHO

Injectors do not always fuel linearly at different pressures and duty levels, so if the ECU knows they fuel less at some point then it might have a compensatation in the map. When you increase the pressure you are also moving these compensation points all over the shop because the compensation is different due to it being at a different pressure - same goes for messing about with the boost (as that also directly affects the fuel pressure - the pressure is regulated by a feed to the boost), which is why you end up with lean spots and over rich spots after upping the boost. I would say that this is a lot of the reason why people get different fuelling results with the GTech chips.

The ECU will compensate to a certain extent when you fit a different regulator, but there is a limit to its adaptability.

Finally, I would echo Rog's sage advice - if you mess with the fuelling or boost in any way (including some of the fairly simple mods) then you should always get your fuelling checked out.

i do run a walbro 255 fuel pump.
you could see my mods in the beginning of the post.
gt 28rs
pace fmic
2,7 decat
walbro 255
str.induction pipe
bonalume dump valve
gtec ii

and a prv from cosmo,not fitted yet.
ebv contrilling boost.
what should i do with all this mods?????
use the prv?
what boost?
use the 4.0 regulator?
??????
?????
??????

your opinions from all of you mates,much acceptable.
thank you all guys...

fit the PRV at your desired boost level, then get the car on an RR for a fuelling check.

if you have ANY lean spots then you need to look at some kind of mapping.

mapping will find out if your mechanical setup needs uprating further, or if you have adequate fuel supply throughout the rev range.

I run an identical setup to you Chris also with a gtec ii.

I haven’t had chance to get down a RR to get my fuelling checked, so I have been running at 1.2 bar for about 3 months it seems fine no signs of pinking but i will continue to run low boost until I get it checked.

IMO you dont need a higher fuel pressure reg if you have a walbro 255 fitted there will be plenty of fuel at the rail, the uprated reg would only be needed if you were still running the standard fuel pump.

I think some peeps are getting a tad confused.

Yes, the ECU dictates how long the injectors stay open (the duty cycle) so a higher rated FPR wont affect this but....

The ECU is not the only thing that determines how much fuel is injected into the engine; fuel pressure also factors into this equation. The higher the fuel pressure, the more fuel is injected. The Fuel Pressure Regulator regulates the fuel pressure. The ECU does not control the FPR; it is controlled by your engine vacuum/boost. At idle when engine vacuum is high, it opens the valve lowering fuel pressure. At higher RPM's when boost is high the valve closes increasing fuel pressure.

So, fitting a 4 bar regulator instead of the standard 3bar will in theory allow a higher pressure reach the injectors and hence pump more fuel into the engine. This is not a good thing if you dont need more fuel.

As long as the regulating pressure is below that produced by the pump then the size of pump is irrelevant.

All IMO of course.

ok just for example lets say an injector squirts for a duration of 0.5 seconds (just for example) then closes.

with more fuel pressure it will still inject for 0.5 seconds, so the increase in fuel from increased rail pressure will be only small, argueably enough to cause engine problems.

the ECU has no control over mechanical parts, except the ones that it is monitoring through a sensor, i.e throttle position sensor.

paul at PTS advises uprating FPR's, saying it will enable better mapping with increased fuel pressure, but that isnt any good if the pump cant flow enough fuel to keep the rail pressurised wnough when at high RPM for long periods.

interesting discussion this.

Yep, agree with all that Rog.

flea - off topic, what mods you running to get 360bhp and what boost?

yeah flea,tell us your mods-boost
dan20vt,i do the same,run the car on ebv and 1 bar until i get it checked on a rolling road.
rog20vt you have been realy helpfull mate...

Also another thing with running a 4.0bar FPR and 1.2bar of boost, means you are putting the 255 pump near to lockout on fuel. These pumps are not good for high fuel pressures, running a combined 5.2 fuel pressure means the fuel pump is only going to be flowing a certain amount and wont be anywhere near the 255l

thanks begbie.....




would the 4.0 bar fpr work better with the coupe 20vt oe fuel pump?
or just the same?