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Discussion Starter · #1 ·
Hi,

I have been told that a bleed valve on my AGU 1.8T will get me running around or just below the 200BHP mark and has been done to a few Cupra Turbos and golf Turbos with owners finding this much more reponsive over various re-maps like Revo etc, (I already have The Carbonio, Forge 007p and Miltek SS). The bleed valve is around ?70 V's Revo at ?398 inc vat ?

Too good to be true ???
 

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I would suggest that a bleed valve would not be the best way to go about things. You need to take into account fueling and other factors which the remap will deal with, whereas as far as im aware bleed valves just mess with boost?
 

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Discussion Starter · #3 ·
Basically the 3 guys all said it's tried and tested with their customers who now are very happy and one owner drove a car with a bleed valve and some other stuff with a laptop plugged in and so impressed he ended up getting revo removed!!

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I spoke to them again, Basically for less that ?80 they will fit a bleed valve, plug in their laptop and sort the car to a very useable 200ish BHP (with my current mods) . They seem to know their stuff as they mainly specialise in forced induction for VW / Seat.

http://www.stormdevelopments.co.uk
 

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You do have to ask, if this was true why doesn't everybody do it? The only times I have anybody come in with a bleed valve is for us to remove it and remap with REVO because they have had so many problems.
 

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Discussion Starter · #5 ·
They don't just fit a bleed valve, they plug the laptop in and work their magic. Just had confirmation from another member that went to the same place said it totally transformed the car.

Well, it's going in next week. I will report back and let everyone know as I have driven 2 Revo'd MK4's already. Once done I will get it on the RR to see what its pushing etc
 

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Make sure you have a boost gauge in there then. The ECU supposedly has mapping tables in it, that will cater for boost up to 14.7 psi (someone correct me if I am wrong). Quite a lot more than standard.. More boost beyond that, and you are going to start causing expensive engine damage. So the gauge is absolutely essential.
But even then, the ECU wont be as optimised at these boost levels, as it would be if you had a proper remap. Especially a custom remap.
So you will get gains with a bleed valve if you are careful, just not as much as you'd get if tuned properly.
Personally, i'd skip the valve and do a proper job of it instead.
 

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Bleed valves run ok and will make the car quick (had one on mine for 6
months) but you will lose out on driveability.The turbo will feel like
its on an on/off switch and as our cars run rich anyway your gonna be
using a lot of fuel.With a chip your fueling and timing is adjusted and
usually the closed loop state that the ecu runs in (eg 0- 3000 rpm
brought down to 0-1500 rpm). With a bleed valve you are just running
withing the parameters of the ecu standard mapping.So your engine will
not be running to its full potential as it would be with a chip.You
will also notice that the car will probably start to feel a bit
sluggish as the ignition timing is retarded over a period of time by
the ecu as it adjusts to the higher levels of boost the turbo is
producing.The ecu will also retard the ignition timing if the turbo
exceeds max expected boost level for more than say 3 seconds and may go
into limp mode.

My advice would be to get a relatively cheap chip like an upsolute one
and you could even use a bleed valve on that map to bring boost in
quicker and control the level that it peaks at this way you get a
decent map with a faster spool up and boost held for a bit longer.

Its the best way really if you want reliability.

Oh and before you go near a bleed valve make sure you have a boost
gauge and at all costs once set resist the temptation to "wind it in a
bit more"

.
 

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Ive got a agu engine and had a bleed valve fitted for nearly a year, yes it did make the boost higher and did make it accelerate quiker. I had no problems with it.

I eventually got it revo'ed and it was the best ?450 id spent on it. Not only did it accelerate quiker than with the bleed valve but kept going and going and going!

With the bleed valve the acceleration used to tail off before 100mph and not seem to have much umph but now it goes straight past 120 still accelerating. if your on the motorway cruising and plant your foot down you can now feel the turbo and it pushes you back in your seat rather than not alot happening.

Basically a bleed valve is cheap (i paid about ?15) and does make it faster but the revo (or other remap) is the best and makes alot more difference.

Also you said someone can plug a laptop in to urs, they couldn't on mine, had to take the ecu out and flash (reset) it on the bench. mines a '98 agu.
 

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Would like to know how you get on with that, I have a forge dv and green filter at the mo, was planning on a remap early next year . . . bleed valve sounds like a bargain . . . but potential for problems maybe?? Just wondering if you might get enough boost creep in v-cold conditions to detonate the engine . . .
 

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Bleed valves are ok but not as good as a proper map.Another thing i
noticed also with the bleed valve set to 1 bar is on the motorway you
will floor the car and it will get to a certain amount of revs then
feel like you have come up against a brick wall powerwise.

However that said even running standard boost on a bleedvalve you will
notice a difference in the way boost comes in.With a greater urgency
and stronger.

There is a certain way to set them up to get them to work well and you will need a 3-way valve.
 

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Discussion Starter · #12 ·
so am I right in saying that running a bleed valve + revo and my current mods = a damm quick GTI compared to std form ?

Or is it not worth having revo and a bleed valve together?

thanks
 

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With Revo, CC, Upsolute, etc you get better fueling and boost settings
as well as timing and other perameters that are altered to obtain
higher power figures.But if you had a chip and were to unplumb the N75
(leaving it pugged in to the power) and set up a bleed valve to peak at
the same boost that was set by the remap you will spool up quicker and
harder because the N75 works in an on/off manner to produce a nice
smooth boost delivery allowing the wastegate to creep open eventually
fully opening the wastegate when full boost is achieved..

A bleed valve set the way i did mine will hold the wastegate shut until
the boost peaks to the amount it has been set to, then it will open up
the wastegate.

Hope that sort of makes sense.
 

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Ive never tried my bleed valve on since i had it revo'ed cause its pretty good as it is. i keep getting tempted to try it but it drives so good i dont want to mess it up!

to be honest i dont think you would need the bleed valve aswell.
 

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Not a good idea running a bleed valve alongside a remap on an agu if
you still have the crappy standard K03 turbo. Using a bleed valve to
raise the boost beyond what the remap takes it up to will take it out
of the turbo's efficiency range, your boost curve will die off much
faster in higher rpm as the little hairdryer can't flow enough air volume and so you will make your car slower with in-gear
acceleration.
 

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i wont try that then. Thats why i never tried it before. I take it you (mkiv turbo) havent got a crappy standard k03 turbo then?! You make me feel so good with my little hairdryer turbo!
 

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Ive never tried my bleed valve on since i had it revo'ed cause its
pretty good as it is. i keep getting tempted to try it but it drives so
good i dont want to mess it up!

to be honest i dont think you would need the bleed valve aswell.
No its not a good idea to run more boost than the remap supplies.But if
you set a bleed valve to run the same amount of boost as the remap

supplies you wil notice quicker response than the N75 valve.

Even on my standard engine if i set a bleed valve to run the same
amount of boost as standard it will pick up quicker than the N75 valve
due to the it being a solenoid and the boost being feathered in rather
than being controlled by the amount of boost that can reach the wastegate actuator.
 

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Discussion Starter · #18 ·
Guys, slightly changing the subject from bleed valves .......... On Revo (AGU engine) would this be ok on a engine like mine thats done 120k on the clock ?

Its been well loved, serviced and looked after, engine and other components are in good health and if anything the engine seems better as it's clocking up more miles [:O]
 

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one owner drove a car with a bleed valve and some other stuff with a laptop plugged in and so impressed he ended up getting revo removed!!
What kind of other stuff?

As i find that very hard to believe, why would you just discard your revo when you paid ?600 for it?! lol
 

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j15mes, mines done just over 120k and i thought the same as you, the revo dealer said if its been looked after and regular oil changes should be no probs.

Had mine done about 6 months ago now with no problems at all. much more fun!
 
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