fuel pressure reg upgade!!!

[wilvo]

Dont know if any ones has done this but iv tried something that i did to my vectra gsi. The standard fuel regulator is set at 3.0 bar but if you fit a fuel regulator from a vectra 2.6 (Y26SE engine) its set at 3.8bar might not sound much but it works quite well, seems to boost lower and you get a nice burble on over run from exhaust. The part number is 9198822 and its alot cheaper (at about £13) than those power boost valve thingys that i dont particually trust. Its really easy to change just lift vehicle or get underneath, on drivers side above steering rack is the regulator undo to torx 25 bolt and gently pry from housing *carefull* as fuel may dribble down, pull off vacum hoseand rebuild in reverse order.. nice cheap mod it made a little difference (Every little bit helps) here's some pics.

[shemtek_racing]

how would this effect an me7 car? is this a proper fit for the one removed?

[Niles]

fuel pressure regulator on an 850 is held under the fuel rail. No need to 'lift' the car. What Volvo are you fitting this FPR to?

[jer,c70]

how would this effect an me7 car? is this a proper fit for the one removed?

i'd like to no too, as ive got a veriable fuel pressusre regulator but dont no if it will work on my c70 gt me7

[Dangerous Dave]

On later 850s the fpr was moved behind the engine at the bottom just by the steering UJ (see the third pic).

[wilvo]

my car is a 1998 s70 t5, the idea behind more fuel pressure is when injector opens for set time there is more fuel let in, more fuel more bang... not sure about later volvo's but if they have the same type of reg this will fit, regulators have pressure value stamped on side... will.

[Niles]

mines a '96 85 T5 & the FPR is under the fuel rail. Honest!! Its NOT round the back of the engine.Promise!!

[pangster]

my car is a 1998 s70 t5, the idea behind more fuel pressure is when injector opens for set time there is more fuel let in, more fuel more bang... not sure about later volvo's but if they have the same type of reg this will fit, regulators have pressure value stamped on side... will.

I understand the theory behind this but I'm struggling to see where any advantage would be made as most T5's run pretty rich anyway - especially in the higher rev ranges - which appears to be typical of most turbo engines as they do this to cool the cylinders.. Introducing too much fuel and running too rich can cause cylinder wash which is when the oil film from the cylinder bores is washed away prior to ignition and results in piston ring to cylinder metal on metal contact (not a good thing)..

On a highly tuned/modified T5 where boost has been increased (massively) with supporting mods i.e. larger turbo, forged engine internals etc I can see where this might be advantageous (along with a bored out fuel rail, larger injectors and performance fuel pump) but for 99.9% of T5's where the stock injectors are more than capable of handling the requirements of a remap or boost increase via EBC/MBC, I can't really see where there would be any benefit - although it would be good to see dyno plots before and after this mod to see exactly how it effects fueling.

[Al115]

THB this seems like a really bad idea unless part of a planned fuelling upgrade? I wouldn't just try it out on my own car! Brave man. :)

Have you noticed any change in fuel consumption btw?

[woz]

I understand the theory behind this but I'm struggling to see where any advantage would be made ..............

Agree entirely - unless the standard item is restricting fuelling which t.b.h it should not unless it is faulty (in which case replace with new) or as you say if the engine has been uprated to the extent the fuelling needs go outside the design parameters of the standard item. And it is only the fuel line pressure that is changed here with this proposed change. You would only need to change it if :
the extra power required so much extra flow that a higher pressure was required;
you have changed to injectors requiring a higher line pressure;
a regulator which could pass a higher volume without pressure drop was needed and maybe this item does that(?).

As you say mate - do it as "Part of a planned series of mods" - not just a willy nilly upgrade.

I would recommend NOT doing this mod unless you have seen a before and after set of dyno plots - inlucing power/torgue and fuel ratio! Same with any other "snake oil" mods.

Did not want to butt in on this one - I hoped the thread would would just die away, but had to chip in in the end.
Cheers
Woz

[pangster]

Agree entirely - unless the standard item is restricting fuelling which t.b.h it should not unless it is faulty (in which case replace with new) or as you say if the engine has been uprated to the extent the fuelling needs go outside the design parameters of the standard item. And it is only the fuel line pressure that is changed here with this proposed change. You would only need to change it if :
the extra power required so much extra flow that a higher pressure was required;
you have changed to injectors requiring a higher line pressure;
a regulator which could pass a higher volume without pressure drop was needed and maybe this item does that(?).

As you say mate - do it as "Part of a planned series of mods" - not just a willy nilly upgrade.

I would recommend NOT doing this mod unless you have seen a before and after set of dyno plots - inlucing power/torgue and fuel ratio! Same with any other "snake oil" mods.

Did not want to butt in on this one - I hoped the thread would would just die away, but had to chip in in the end.
Cheers
Woz

well put Woz and Al115.. I think people should be wary/concerned about altering their fueling almost as much as altering their boost without first looking into it a bit..

It's good to know that this mod exists and is a fairly cheap alternative to a performance after market item - but I can't see this ever being needed in 99.9% of T5 applications.. I think there are a few T5's on here and elswhere running between 300-350 bhp which don't have any issues with fueling in relation to the stock FPR and the vast majority of T5's aren't even at this level and probably never will be then this is something that probably won't ever be required.

[p fandango]

just phoned my local Vauxhall dealer, £22.60

[Niles]

On later 850s the fpr was moved behind the engine at the bottom just by the steering UJ (see the third pic).

later??!! mines a '96 And the fpr is under the fuel rail

[dangerstevie]

Upping the fuel pressure is a bad idea on the standard injectors. From what i tried at uni upping the fuel pressure messed up the spray patterns of the injectors and promoted fuel droplets from the injectors (instead of atomised fuel spray) bad for both power and economy, would be interesting to see the difference in spray patterns and flow using the std injectors and the raised fuel pressure. Maybe jimathon with his injector test rig could up the fuel pressure to 38psi and see what the difference is on a std set of injectors if he didn't mind and everyone asked him nicely and also if he had time.

[Alan M]

The fuel pressure at 0 manifold pressure is 3 bar 43.5psi and with a vacuum pulled will be lower slightly and with a boost increase will be above depending on the boost increase. Thats how I have read the info I have seen and understand how our car works. I have also had a liquid filled pessure gaue rigged up on the rail and saw this affect for myself.

[Saaamon]

For any turbo car you need a rising rate fuel pressure regulator..

Saaamon

[turbotony21]

bring on bore wash and thinning down the oil we this mod would love to see how much fuel is in ure sump after few weeks of running pretty bad idea without being on a dyno aswell like just askin for trouble

sorry had to comment

[turbotony21]

holy jesus just noticed thread was 2008 pmsl

[MoleT-5R]

bring on bore wash and thinning down the oil we this mod would love to see how much fuel is in ure sump after few weeks of running pretty bad idea without being on a dyno aswell like just askin for trouble

sorry had to comment

took your time about it......lol

but it is funny as I was currently thinking of trying this mod this weekend at york for a couple of back to back 1/4 mile runs and let the clock tell the difference, if any...!! as I don't really have a friendly local rolling road nearby to test it on

[p fandango]

the fpr from a Fiesta 1.6 Zetec is a 3.8 & fits the 850 fuel rail (Bosch 0 280 160 599, Ford 98MF - 9C968 - BB)

[turbotony21]

why not just fit an adjustable fuel regulator to up the rail pressure least u can play with the setings to see whats best

[MoleT-5R]

why not just fit an adjustable fuel regulator to up the rail pressure least u can play with the setings to see whats best

nothing really but I have the 3.8 bar sat here on the self just waiting for its day to come......just like many of the bits I pick up as they appear and then sit awaiting there time to shine..:)