S40 t4 twin piston dump valve open at idle. Boost drop.

[gmain1967]

AFAIK, DV26 has two versions. If car runs right or has run right, you have twin piston type (correct). If no boost leaks from hoses then I would suspect you have a problem with actuator (diaphragm). Even if untouched, they wear and will leak when pressure (boost) applied. Other would be that if higher boost, either spring in DV has gone weak, or is not capable of holding higher boost. To check either/both, open valve up and put a shim (coin will do) in to shorten the spring. This will effectively stiffen it and allow it to hold more boost. DV's do work if correct for the setup.

[960kg]

Originally Posted by Volvulate

Djx said he had full boost right to the line....

If your talking standard T4 1855 you will even at 19psi of boost which i ran for over 2yrs. with no problems

Originally Posted by Volvulate

If the turbo is capable of boosting higher surely it can sustain boost pressure at high revs. Ive heard you can turn them wayyyyyyy up, obv at cost of killing it.

Yes, you can turn them right up as a member on here did he got 26psi for a week before it blew the engine bearings, (with a standard map)

Another on here with another standard map blew the HG because it overboosted to 26psi `ish as the old small boost hose gave up on the turbo, so you can see clearly that with a Phase 1 T4 the ECU does not control the boost, if any of the things are missing or are not the correct value which gives you the boost then the ECU will not allow it ....this is a different thing.

A remap removes the limit of boost it does not create another limit as this is the point of having a new map so you can custom the tune!

[Volvulate]

This has a mte stage 2 remap. When does your boost start? Cos mine is like instant, maybe 1200 - 1500rpm....

[mitchyboy01]

Originally Posted by 960kg

a remap removes the limit of boost it does not create another limit as this is the point of having a new map so you can custom the tune!

lol! Ok. (wrong)

[mitchyboy01]

Originally Posted by 960kg

you can see clearly that with a Phase 1 T4 the ECU does not control the boost

LOLOLOL hahahaha I was running a MBC in place of the BCS! Therefore the name MANUAL boost controller, you take control away from the ECU!

The BCS is controlled by the ECU and therefore boost is controlled by the ECU whether phase 1 or phase 2, remap or no remap. A remap raises boost via the BCS (to a preset limit programmed by the mapper)! Unless you overide it with the 'dreaded' MBC.

[960kg]

Originally Posted by mitchyboy01

LOLOLOL hahahaha I was running a MBC in place of the BCS! Therefore the name MANUAL boost controller, you take control away from the ECU!

The BCS is controlled by the ECU and therefore boost is controlled by the ECU whether phase 1 or phase 2, remap or no remap. A remap raises boost via the BCS (to a preset limit programmed by the mapper)! Unless you overide it with the 'dreaded' MBC.

I do sometimes Mitch wish you would stay in that bottle of Vodka........ this is the reason you don`t read correctly Ha! Ha!......

I am talking of my own experience with my Phase 1 T4 1855 as i personally would not want the more delicate 2 litre engine or any 83mm bores engines.

The BCS keeps the start of the boost in a safe rev. and engine load area and limits it in 1st & 2nd gear to a reasonable amount to prevent damage but then in the rest of the gears the boost will be allowed whatever the actuator is set at...

You know i always used the standard BCS and my boost was set with the actuator at 4 turns which gave me 19psi ........NOT at any stage did the ECU cut the boost as it cannot on a Phase 1 map, it is NOT built into it.

So now we go on to my V70 T5 with a new BCS it went well but only boosted to 9 /10psi which is standard set for this model.

I turned up the actuator 4 turns, same as on the T4, it only boosted to 15psi and then cutout, it would not go above 15psi as this is the maximum boost the ECU will allow.

Next thing to get more boost was a remap and this removed the boost limit and depending WHO does the map it was not replaced with another higher boost limit.

I fitted my remapped ECU went out with the same settings and hit 20psi WITH the same BCS.......so again the boost limit was removed and not replaced with another. In any case where would you want another limit placed, it is total nonsense. Would you pay £450 for a map and still be limited for boost, i don`t think so as you would be reasonably experienced as what to expect if you got it wrong.

I now have an MBC fitted to the T5 and when setting i tried it for 25psi and it did get there easily without cutout. The safe max. is 27psi but not for running permanently as damage results.

Have a little read if you can focus and you will see why a Phase 1 T4 does not have a max. boost limiter. The ECU will only reduce the boost via the BCS when the engine knocks due to the wrong fuel on high boost or the engine is overheating or when the MAF and other sensors have failed it then goes into limp home mode.

O, by the way if you haven`t got a conversion chart 190kPa = 27.55 psi

[Volvulate]

Lol none of you have answered my question. Just bickering lmao. Propa busy at garage and not had chance to do leak test yet. Also since I sorted out my dump valve, the eml back on p0141. That dv is going. Whats the r-type like? The stealth thing lol. Might get that. Also what is it like to rebuild turbo? We send ours off, but I saw a rebuild kit on ebat n it dont look so bad lol. Be nice to have that re-assurance! Ive aquired loads of lil jubilee's so will be taking all the daft blue tie wraps amd gettin some propa clampage. So when does your boost kick in on phase 1 t4?

[mitchyboy01]

Right then, thanks for yet more incorrect drivel.

I am talking of my own experience with my Phase 1 T4 1855 as i personally would not want the more delicate 2 litre engine or any 83mm bores engines.

What's so "delicate" about the 83mm T4 bores? There's quite a few cars that have made over 300bhp on standard engine and they don't suffer anywhere near as bad the liner issues of the 5-pots! Also, what is the difference between the way the BCS is controlled between Phase 1 and 2 cars, if so, which map no (of the 600+ there are in the EMS2000) are you saying is different?


The BCS keeps the start of the boost in a safe rev. and engine load area and limits it in 1st & 2nd gear to a reasonable amount to prevent damage but then in the rest of the gears the boost will be allowed whatever the actuator is set at...

WRONG! The axes of the BCS duty cycle maps (all al them) are not based on engine speed vs engine load - they're based on air consumption per stroke (mg/tdc) vs rpm. In addition the boost "limit" in 1st and 2nd gear vs 3,4 and 5 is actually down to the fact that they're 2 totally different maps, and the gearing of the car (to aid in traction, not prevent damage!).


You know i always used the standard BCS and my boost was set with the actuator at 4 turns which gave me 19psi ........NOT at any stage did the ECU cut the boost as it cannot on a Phase 1 map, it is NOT built into it.

That's because the MAF limits (air consumption) are already set quite high from the factory and at higher boost pressures, the tiny 14T will start to choke and become less efficient - so higher boost does not always equal more power as the air consumption can and WILL fall if other (suitable) parameters are not altered at the same time.


.....and you will see why a Phase 1 T4 does not have a max. boost limiter. The ECU will only reduce the boost via the BCS when the engine knocks due to the wrong fuel on high boost or the engine is overheating or when the MAF and other sensors have failed it then goes into limp home mode.

This is the biggest piece of BS there is in your BS post! - so some questions then - what is the threshold boost / rpm / coolant value for knock correction activation in the EMS2000? There are several other VERY BASIC situations in which the ECU will limit boost (without going into limp mode), let me know your view on this 960. I'm interested to hear more BS, it's entertaining and certainly very funny.

[mitchyboy01]

Originally Posted by Volvulate

Lol none of you have answered my question. Just bickering lmao. Propa busy at garage and not had chance to do leak test yet. Also since I sorted out my dump valve, the eml back on p0141. That dv is going. Whats the r-type like? The stealth thing lol. Might get that. Also what is it like to rebuild turbo? We send ours off, but I saw a rebuild kit on ebat n it dont look so bad lol. Be nice to have that re-assurance! Ive aquired loads of lil jubilee's so will be taking all the daft blue tie wraps amd gettin some propa clampage. So when does your boost kick in on phase 1 t4?

Sorry for the bickering mate. Although it seems childish, the reason I haven't let it lie is because what he has posted is incorrect and I don't want forum members taking his incorrect info as gospel.

[Volvulate]

And now maybe my questions..........ya know.....while your there n that..