Yes, that's it. Sadly i'm not really familiar with the LCR, but since it is an emissions device (whole sec.air stuff) - i doubt they threw it out.
Tony20VTurbo
Guest
Sim said:The N249 valve is (should be) there for safety reasons i believe. It is there for one and only purpose: it gives the ECU control over on the DV at full throttle (when no vacuum is available). Just read my first post - it can also help N75 to regulate boost, too. Also its name "Turbo Bypass Valve" tells it all. No tuning engine wants to bypass the turbo.
Ok cool, thanks for that mate
but just another question i read from the Vortex forum, the main point of this is to allow the turbo to sustain higher amounts of boost higher up the rev range
for example with the N249 valve, some people are running 13PSI at 6000RPM with a chipped car
without the N249 valve, people are now running 17PSI at 6000RPM wth a chipped car
now that increase of 4PSI and 6000RPM , surely that is creating alot more strain on the turbo no? i just need to know if the K03S can really cope with that amount of battering, not that it already doesn't but you can see my point, the N249 valve being in place to perhaps prolong the turbo a bit more.......
maybe i am just being too cautious, but maybe something to bear in mind if i am half right?
what is the threshold for the K03s anyway? i know Jabba map it within its capabilities anyway so not to risk detonation of course, so i hope the N249 valve wont really cause much more strain on the turbo...........
cheers
Tony
to be honest i really cant see a 4psi increase in boost at 6k rpm. if it did, every fokker would be doing it....
Shock_Xe
Guest
I think vwvortex prolly quotes on a big turbo i.e. garret as they are as common over there as chipped cars here. Considering size diff, realistic I reckon it may add 1-2psi max which is a nice gain but not dangerours.
FYI Max boost of a k03s is 1.8bar, I ran 1.5bar for a while with no probs, I think you guys run around 1.4
Hopefully gonna finish this mod tomorrow as I just got me samco, All the resitors are soldered up, just the plumbing to do.
FYI Max boost of a k03s is 1.8bar, I ran 1.5bar for a while with no probs, I think you guys run around 1.4
Hopefully gonna finish this mod tomorrow as I just got me samco, All the resitors are soldered up, just the plumbing to do.
Hmm. I dont think my boost is any higher with this mod (maybe a little bit), though car feels (responses) faster for sure .
.
Sim said:Hmm. I dont think my boost is any higher with this mod (maybe a little bit), though car feels (responses) faster for sure
smoother and more responsive.
Shock_Xe
Guest
done the plumbing, just gotta hook the resitor up to see if it works, Will report back laters
sim you may be interested in this thread, similar to yours
and while bypassing things this
Im looking at different n75 by passes, u have the mbc and the one in the thread which looks complicated
sim you may be interested in this thread, similar to yours
and while bypassing things this
Im looking at different n75 by passes, u have the mbc and the one in the thread which looks complicated
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I have been fooling with the MBC for several months. It was a great alternative of raising boost, but it wasn't perfect. The mbc for me dropped the boost linearly, don't know why. Lets say i've set 14 psi @3000, and it got dropped the boost to 10psi @ 6000. Then i set it to 10psi @ 3000, it got dropped the boost to ~6psi @ 6000. Don't know why. I already asked the answer here, but got nothing.
Then i got into "chipping" (mainly due to this reason - and because i was not satisfied with the mapping they did over here for huge $$$$s) and removed the MBC. Now i'm happy with my boost levels (as happy as i can be with the small K03.
Had a thread about this on Tex:
http://forums.vwvortex.com/zerothread?id=912542
And over here (nobody was interested):
http://www.seatcupra.net/forums/showthread.php?t=19705
http://www.seatcupra.net/forums/showthread.php?t=24761
Then i got into "chipping" (mainly due to this reason - and because i was not satisfied with the mapping they did over here for huge $$$$s) and removed the MBC. Now i'm happy with my boost levels (as happy as i can be with the small K03
.Had a thread about this on Tex:
http://forums.vwvortex.com/zerothread?id=912542
And over here (nobody was interested):
http://www.seatcupra.net/forums/showthread.php?t=19705
http://www.seatcupra.net/forums/showthread.php?t=24761
The images have disappeared. So here are they again (though these may belong to an other topic). As you can see, you may reuse your N249 valve .
.jonathanp said:
N75 HAS to feed boost back to the intake preventing it from going to the wastegate to RAISE the boost level. Without N75 feeding (bleeding) back any boost, the wastegate would open at ~0.3-0.4bar (limp mode boost levels).
sorry I meant why doesn't the N75 act like a dawes device, you have your boost pressure contained via a solenoid then when it opens it goes to the wastegate................so rather than boost feeding in to the intake it will keep building until its released to the wastegate
seems odd that the n75 feeds boost to the intake but its generally a bad thing when a DV splits and feeds boost to the intake as well
seems odd that the n75 feeds boost to the intake but its generally a bad thing when a DV splits and feeds boost to the intake as well
jonathanp said:
its not an on/off valve tho its a frequency valve... which is how it bleed adjustable amounts away as requested by the ecu.
Anyone know if a n75 can fail to the extent where a previously mapped ECU that was requesting 19 pso only now requests 15 psi?
Rgs
Dor.
P.S. Is there and difference between the F N75 and the C N75?
Rgs
Dor.
P.S. Is there and difference between the F N75 and the C N75?
jonathanp said:
For safety reasons! By default, all boost is going to the wastegate causing a maximum of ~5psi (0.3-0.4bar). When N75 is energized, it bleeds a fixed amount of (on some types it is adjustable with a screw) air to the inlet, making the boost to rise until the desired level. If anything goes wrong (N75 locks up, or anything) the turbo can not overspool. Also if you'd close the route to the wastegate completely, perviously entered boost could not escape from there and wastegate would stay shut. This way vacuum can suck air out from there, closing WG as fast as possible.
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Anything may happen. :| Though when i broke my N75, it was no boosting at all (constant limp mode).
Have you tried to make the ECU to re-adapt things?
Have you tried to make the ECU to re-adapt things?
Thinking that its basically a rubber diaphragm in the actuator, the air needs to be able to move in and out, hence bleed to a low pressure side (intake)jonathanp said:
Sim said:
when mine broke (realised last week) it made uncontolled boost whenever it felt like it.
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