Fuel Pump Regulated To 4 Bar?

[Saveit 0]

Hi there,

 

I am about to fit a new enginemanagement to my 205 1.6 gti. The guy doing the work tell me that he would use 4 bar fuel pressure instead of the 3 bar which i think the standard gti is running?

 

Now the fuel regulator is that the round thing at the end of the fuel rail? Do you know which cars have a 4 bar regulator fitted that i can get it from? And lastly, how will the fuel pump cope with 4 bars instead of 3?

 

 

Stefan

[Saveit 0]

Someone? Would at least just like to know if the pump can cope with 4 bar pressure..

[Tom Fenton 1,542]

Don't see the point. If you need more fuel go up on injector size.

[Saveit 0]

The guy tells me that the spray pattern is better at 4 bar? But can it cope?

[maxi 36 1 Cars]

I run 4.5BAR on a std pump. I use an FSE fuel pressure regulator. Im also using cossie yellow injectors. I also have 202BHP @ the wheels.

 

Maxi

Edited July 3, 2009 by maxi

[RossD 44]

Some of the mid-90's Audi V6 cars have a 4bar regulator. I got one ages ago but never used it!

[maxi 36 1 Cars]

For fu cks sake just buy an adjustable fuel pressure regulator. Set the pressure. Job done.

 

Maxi

[sideways danny 0]

adjustable regulators are nasty and unstable. Use a Webcon regulator. I'd have gone for 3.5bar personally, but go with what the people doing tha mapping have asked for

[Mad Professor 7]

If it was me I would stick with the standard 3bar, and fit some Bosch EV6 Injectors.

 

The new style Bosch EV6 Injectors have a much better spray patten and atomisation.

 

Heres a quote from Bosch

 

Fuel velocity through a pintle type fuel injector [type code EV 1] can dramatically affect its ability to atomise fuel. The profile of the pintle used in a fuel injector has a direct relationship to the operating pressure it is designed to operate under. Whilst Bosch produce various fuel injectors that may flow the same amount of fuel at a given specification, the system operating pressure will influence the pintle profile. Correct pressure will result in a well atomised spray, while insufficient pressure will result in a “hosing” effect. Excessive pressure will result in either “hosing” or a spray angle that is too large for the targeted area dependent on the pintle profile.

 

The consequence of excessive fuel pressure on a pintle type injector may well be that as the pressure is increased the mixture values of the engine may appear to get leaner. This is of course not the case, but the fuel being injected is no longer atomised and is entering the cylinder as a liquid mass. This will typically cause the Hydrocarbon [HC] values to rise due to the raw fuel exiting the cylinder, and the Carbon Monoxide [CO] to drop due to insufficient combustion.

 

Later design fuel injectors [type code EV 6] use “director plate” multi-orifice technology to better atomise fuel across various operating pressures. These injectors allow more flexibility in relation to operating pressures without compromising spray efficiency or fuel atomisation.

[sideways danny 0]

If it was me I would stick with the standard 3bar, and fit some Bosch EV6 Injectors.

 

The new style Bosch EV6 Injectors have a much better spray patten and atomisation.

 

Heres a quote from Bosch

 

Prefer the siemens deka injectors myself, but they're of the shorter size (pico equivalent) Same theory though, 8 spray holes.

[maxi 36 1 Cars]

adjustable regulators are nasty and unstable. Use a Webcon regulator. I'd have gone for 3.5bar personally, but go with what the people doing tha mapping have asked for

 

 

Are they? Care to explain and justify your comment??

 

Maxi

[DamirGTI 342]

I have an FSE valve as well (fitted in order to balance out air/fuel mixture on engine with ported head .. as i've had problems with way too lean fuel mixture after engine mods..) and i can't say anything against the thing it just needs to be adjusted properly and adjustment is a bit sensitive so it's best to do than on a dyno/rolling road if possible ..

 

Damir

[sideways danny 0]

Are they? Care to explain and justify your comment??

 

Maxi

 

 

lots of dyno time proved that they changed pressure, sometimes drastically, from one run to the next. It became so frequent that we stopped mapping cars with an FSE fitted unless it was replaced with a fixed pressure reglator.

[maxi 36 1 Cars]

lots of dyno time proved that they changed pressure, sometimes drastically, from one run to the next. It became so frequent that we stopped mapping cars with an FSE fitted unless it was replaced with a fixed pressure reglator.

 

 

Was this only FSE's or did it include bosch items too? How about the std cossie ones? Also were they old worn out units? How did you notice pressure change, did you have the gauge left plugged into the side?

 

Maxi

[sideways danny 0]

the cosworth adjustable one is the exception. Not available new any more I believe??

 

It's the FSE item that's been the issue. Random fueling changes without any changes to the map were the initial problem, so gauges were added to monitor.

[welshpug 1,661]

is the Webcon item the one that fits in place of the regulator on most of the later fuel rails like the S16 and gti6 use?

[sideways danny 0]

is the Webcon item the one that fits in place of the regulator on most of the later fuel rails like the S16 and gti6 use?

 

 

2 types of the same thing, there's a remote one that fits where you want it with changeable regulator cartridge, or just the cartridge itself like is common on a lot of rails. I'll be honest, i'm not overly familiar with the specifics of the s16 and gti6

[sideways danny 0]

 

or

 

[welshpug 1,661]

second picture is what a lot of cars use now, inc the S16 and GTi6, the often mentioned VW VR6 4 bar regulator us one like this.

[Saveit 0]

Does s16 and GTI6 run 4 bar pressure?

[welshpug 1,661]

no, 3 bar.

[wracing 19]

don't raise your fuel pressure by a silly amount there is no point. increased fuel pressure increases injector opening time, heat dissipation, and driving current required, not to mention the poor little fuel pump!

 

im getting worried about all these 'mappers' who turn things up and quote that it works better.

 

3 bar std is set as it achieves an equilibrium between mtbf, inefficiencies and good fuel delivery.

 

i think people should state their information source/reasoning and not just quote 'mappers' to avoid any misdirection/misinformation been passed on to others.

 

james

[bales 1]

don't raise your fuel pressure by a silly amount there is no point. increased fuel pressure increases injector opening time, heat dissipation, and driving current required, not to mention the poor little fuel pump!

 

im getting worried about all these 'mappers' who turn things up and quote that it works better.

 

3 bar std is set as it achieves an equilibrium between mtbf, inefficiencies and good fuel delivery.

 

i think people should state their information source/reasoning and not just quote 'mappers' to avoid any misdirection/misinformation been passed on to others.

 

james

 

Bit of a random question but how old are you James? and are you currently at university studying engineering?

 

The only reason I ask is that you sound a little like me a couple of years ago, a lot of your posts quote a great deal of theory which sounds like you read a lot of books on the subjects.

 

When I was at uni (especially my 3rd and 4th years when I was working on our race car) I read a huge amount of text books and theory on everything you could possibly want to know about race cars, especially for me suspension design and geometry. If you asked me to set-up a race car to handle well I could quote what the books said but wouldn't have a clue in reality as it isn't something I have physically had a huge amount of experience in.

 

All I am going to say is that theory is not the be all and end all, since I have been working for the last three years (in engineering) the one thing I have learnt is that you do sometimes have to go off experience and knowing the theory behind things is all well and good but doesn't neccessarily give the desired results all the time.

 

I suppose what I am trying to say is that you are questioning a 'mappers' credentials, and it sounds like you want people to fully explain their reasoning using in-depth theory. Sometimes people don't know the theory but they know what works and what doesn't through experience. I have been to a number of rolling roads, and the best two guys have been the sort of people who didn't go to uni and probably dont know the in depth theory behing things, but they did know absolutely what to do with cars and what works and what doesnt just through the experience they have had...

 

So I suppose to respond to your question do you have a great deal of experience with injectors on test beds, investigating how spray patterns differ with fuel pressure and what the additional heat is created etc etc..and measured the heat dissipitation of the injectors when running at higher or lower fuel pressures, have you run cars on rolling roads and actually seen the measured differences....

 

Or is it because you have read theory on how injectors should behave under different pressures?

 

I'm not trying to be offensive to you at all as you do sound like a very bright lad, but equally it is a tad hypocrytical to ask people to defend their responses if you cant defend yours??

 

(this is where you tell me you work for an injector company.... )

Edited July 7, 2009 by bales

[wracing 19]

haha nope don't worry about that i don't work for an injector company.

 

im currently halfway through my second degree cybernetics and artificial intelligence and ive got one in automotive engineering(certificate pending). don't ask i'm one of those kids... im 20 yes before you say far to young... im currently having my gap years working as a maintenance engineer as got bored of education.

 

your probably going to say that i have f*** all experience which is true, ive been building race cars since i was 16. completed about 6 now i think ranging from 1300xflow to a 5.7charged locost. as you can imagine i never have any time (from my lack of updates on buildthreads and whatnot)

 

its my opinion that correctly implemented theory underpins practice.

my frustration is what is the point of posting in a relatively technical thread with out any real input and just quoting other people. if some one turned round and said that 'they' found better results by changing certain variables from standard then fair enough.

 

i believe that everything i post has a sound base and it is not just theory. if you can prove me wrong then im willing to be graceful and retract any comments that are incorrect. life is a constant learning curve.

 

to tell the true i have never used a dyno for tuning just power runs. ive been brought up to use sound and feel, my father gets rather cross when he finds my using a lambda!

 

finally i have found that an increase in pressure draws more current and opens slower in practice. the comment about heat is theoretical but can be assumed due to the conservation of energy principle.

 

if you would prefer me not to post theory then i can refrain from doing so.

 

sorry to cause offense i thought that this forum wanted an intellectual input from its users, if mistaken or have come across in the wrong way im sorry

 

james

[Saveit 0]

my frustration is what is the point of posting in a relatively technical thread with out any real input and just quoting other people. if some one turned round and said that 'they' found better results by changing certain variables from standard then fair enough.

 

Well James. I didnt do this post to ask for help (not trying to be offensive) and therefore i didnt post up any additional info - and secondly i dont have any additional info So i cant see the point of being frustrated? Was just asking if the pump could cope with 4 bar pressure.

 

I very much appreciate any help, guidance and theory you you guys post - dont get me wrong. But we made a deal with the mapper. The deal is that he gets the engine setup as he wants, and then the rest is fully his job. Therefore when he tells me to use 4 bar pressure and Siemens Deka (DelphiMini) injectors then i just do as he says. Why should i ask questions? I dont know the answers to the questions anyway, and this is what he does for a living. If the car doesnt run he doesnt get paid

 

Stefan

Edited July 8, 2009 by Saveit