red injectors

jay22s3

2nd gear sorts em out
any guidance please im thinking of getting some red injectors for my car 1999 s3 its been remaped has a 4bar fpr and a aftermarket stainless exhaust system and de cat front pipe, what sort of gain would i get from doing this ? and would the 4bar fpr still be good with the red injectors ? any comments would be much appreciated
 

<tuffty/>

Badger 5 Edition...Its all about the flow...
Staff member
Moderator
No advantage at all.... even the 4bar FPR is too much...

Std injectors on a 3bar FPR will fuel to 280ish hp... 4bar FPR will murder what ever life you have left in your pump and saab reds are a step backwards in size and quality of injector..

<tuffty/>
 

jay22s3

2nd gear sorts em out
ok thanks but ive read about certain company's putting 4bar fpr in after remaping why is this if the 3bar fpr is good enough !
 

<tuffty/>

Badger 5 Edition...Its all about the flow...
Staff member
Moderator
They are designed for large port manifolds and bungs... never tried them in a smallport mani as they are more suited to the older dumb *** ME3.8's and only use Bosch or Siemans injectors when they are needed on ME7 cars which in the case of the OP unless he has a K04 hybrid or a setup exactly like Westy's he won't need them anyway

<tuffty/>
 

<tuffty/>

Badger 5 Edition...Its all about the flow...
Staff member
Moderator
ok thanks but ive read about certain company's putting 4bar fpr in after remaping why is this if the 3bar fpr is good enough !

Revo used to IIRC but nobody in their right mind would recommend one these days... there is simply no need and the fuel pumps are getting tired now due to the age of the cars, a 4bar will just make matters worse...

<tuffty/>
 

jay22s3

2nd gear sorts em out
what sort of code is that then you've lost me haven't got a clue what that means over my head that sorry
 

Westy

Registered User
ok thanks but ive read about certain company's putting 4bar fpr in after remaping why is this if the 3bar fpr is good enough !

There's a lot of tuning companies that don't know what they're doing. A 4 bar FPR is just a work around, not really a solution. It will put extra strain on your fuel pump and you could potentially do more damage by then running lean.

My car was struggling at around 270bhp on the 3 bar FPR and on a brand new fuel pump. I had to get some larger injectors mapped in.
 

<tuffty/>

Badger 5 Edition...Its all about the flow...
Staff member
Moderator
so it would be wise to put my 3bar fpr back on then ?

Do you know for sure if it was mapped for the 4bar? what map do you have?

<tuffty/>
 

jay22s3

2nd gear sorts em out
no it was mapped with the 3 bar fpr and i put the 4 bar fpr on after not sure if it was a stage 1 or 2 re map cant remember i will have to check
 

<tuffty/>

Badger 5 Edition...Its all about the flow...
Staff member
Moderator
no it was mapped with the 3 bar fpr and i put the 4 bar fpr on after not sure if it was a stage 1 or 2 re map cant remember i will have to check

Put the 3bar back in...

The internet is a wonderful place but its so full of misinformation its unreal :)

<tuffty/>
 

<tuffty/>

Badger 5 Edition...Its all about the flow...
Staff member
Moderator
....and just to qualify all this... 4bar FPR adds approx 15% more fuel... which the ECU adapts back out (even on narrow band ECU's like yours)... you acheive absolutely nothing fitting a 4bar in this instance as the map has not been told about the extra fuel and will adapt it out... only thing you have done is make the fuel pump work harder for a living...

Fitting the reds in place of the current bosch injectors give a worse spray pattern so idle and fuel consumption will be affected... the bosch injectors you currently have are just better...

If you NEED extra fuelling then you want Bosch EV14 550's and these WILL need to be custom mapped in else the ECU will just adapt the fuel back out like it will with the 4bar and again you gain nothing but make your car less efficient..

Do you have any other mods on the car? FMIC? 80mm TIP? airfilter? 3" DP?... you would need all of these to warrant a stage 2 map... and even then you may only be in the 270hp region as a rule..

<tuffty/>
 

jay22s3

2nd gear sorts em out
it has a piper cross air filter 3 inch de cat front pipe thats it really
just checked it was a stage 2 remap
 
Last edited:

dan1973

OCD clean
My input on this if it helps any..... I had a LCr with the 225 bam engine. Stage 1 map, miltec, decat and neuspeed air filter etc. we fitted a 4 bar fpr and it didn't like it at all and there where no gains. So we reverted back too the oem 3 bar.
 

S3 Paul

Well-Known Member
Regional Rep
The 4 bar reg on my car was mapped in but... Unless the pump is fresh as a daisy it will huff and puff and struggle long term,
i had to change my pump as power dropped off whe the ecu saw pump struggling to deliver.
although I'm told by the company who mapped it its "safe" it will never make the big numbers as it will run too lean .
the long term result of that is... A new engine
 

jay22s3

2nd gear sorts em out
ive put the 3 bar fpr back in now been on a run to doncaster this weekend and it felt like a different car much better i thought i felt something was not quite as it should be when i put the 4 bar fpr in as it was mapped with the 3 bar in its got its character back now popin and slight back fire and i even managed to fit my front strut brace i bought about three weeks ago what a difference feels so solid now well happy with it :)
 
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