Wategate flutter? Or just an echo?

[Bram]

Mine does also flutter in 3th gear and highergears on full boost from 3300 till redline.
The turbo boost meter remains stable al the time, so I am almost sure there is no leak in the boost circuit. I do now that the ceramic ring in my WG lost a small part when I dropped it on the floor. Now I have a new one and will fit is next Friday. Will let you know if the flutter has gone or not.

I forgot to mention I run a GT3071R at 2 bar. One hose I did not check yet is the one coming from the WGFV (N75) to the WG. That one is currently a silicone hose, which I was told I could better replace by a woven rubber hose due to heat expansion.

[Rusty]

I've yet to check the one-way valve in the breather system that attaches to th IM just after the TB. Could be that it's leaking a little at thie higher boost before it gets knocked back but that really is clutching at straws!

[Animal Mother]

I forgot to mention I run a GT3071R at 2 bar. One hose I did not check yet is the one coming from the WGFV (N75) to the WG. That one is currently a silicone hose, which I was told I could better replace by a woven rubber hose due to heat expansion.

I was looking at that part too. It has banjo bolts doesn't it? Looks like it could easily leak at the join of the pipe to the banjos. Maybe an braided pipe would be the best solution for this?

I've yet to check the one-way valve in the breather system that attaches to th IM just after the TB. Could be that it's leaking a little at thie higher boost before it gets knocked back but that really is clutching at straws!

I think I'm going to fit Samco's replace the PCV parts, the N75 and put a 1.7/1.8 bar WG spring in it. It could also be a leak from the pipe mentioned above. I will look into getting a braided line for that part.

[terrybullwon]

I was looking at that part too. It has banjo bolts doesn't it? Looks like it could easily leak at the join of the pipe to the banjos. Maybe an braided pipe would be the best solution for this?



I think I'm going to fit Samco's replace the PCV parts, the N75 and put a 1.7/1.8 bar WG spring in it. It could also be a leak from the pipe mentioned above. I will look into getting a braided line for that part.

Braided will be a good way to go, try speedflow they will have every thing you need on the shelf.

I would not advise a a stiffer WG spring with your current set up.

[UrS4Eben]

I've also got this kind of sound when I plant my foot... the best way I can decribe it is the creaking sound that huge spring of a tilting garage door makes when you open or close it
No adverse effects though.

[Acidburn]

Mine has had it since I fitted the aby airbox, I never had it beforehand with the d/v that was on the car or the vent to air turbosmart one.

[HPmuirt]

Sorry to ressurect an old thread, but ever since I have been running the RS2+ spec I get a very noticeable wastegate flutter which can be felt through all of the controls.

I can accelerate at 1.5 bar with no flutter and then floor it and it flutters badly until the revs get high enough that the boost has dropped back to below 1.5 bar.

The car is running RS2 Ex cam, EM, turbo & cats but stock ABY after the cats. I know I am therefore running too much back pressure for much over 350bhp even though my chips should be pushing out much more. One cat has recently been emptied which made no difference but could this just be a back pressure issue?

The N75 and DV are both only 2 years old, but the wastegate looks original as I cannot get the top off for love nor money - I think only half a Kg of TNT would shift it!

The WG screw is still capped and therefore not screwed in and mechanical boost with the N75 unplugged is 0.4bar so I have a stock spring.

I have a 0.9bar spring which I tried to fit to see if that would help, but cannot get the damn WG cap off

Any ideas on either the flutter or how to lift the damn WG cap without ripping the diaphram?

Cheers n

Si

[Rusty]

The stronger spring might be a little too much but it's worth a try for sure. AFAIK, the WG flutters because the N75 can't correct the boost fast enough either due to a lazy N75 or a weak WG spring allowing resonance in the system. I get this on the K24 7000 on a homefries and many others have had it. One thing to try is just tightening up the WG cap to give a base boost of 0.6 bar and see how that works out for you. Much more than that though and you're start p'ing the map off with spool that's too fast...

[S2central.net]

Personally - I would NOT wadge in a hairy big spring onto that setup... could cause dangerous boost spikes that may not be limited by software.

As for the WG cap - I've had a few in my time... best advice is to loosen the cap nuts by a couple threads then apply some percussive therapy with a stiff rubber mallet. This is needed to break the grip on the diaphragm. Some care required so as not to damage anything. Once the seal has broken then you can proceed to further loosen the cap nuts.

[R31LLY]

high boost pressure and my forge adjustable re-circ does it, proper rally car style i love ti ;-D

[macspring]

Si,

I presume you saw this recent thread and that this has nothing to do with your particular issue?

http://www.s2forum.com/forum/showthread.php?t=52147&highlight=check+mine

Kind regards.

[HPmuirt]

I presume you saw this recent thread and that this has nothing to do with your particular issue?

http://www.s2forum.com/forum/showthread.php?t=52147&highlight=check+mine

Kind regards.

Thanks, I didn't see that thread so I will check mine, but mine is quiet below 1.5bar and is not a metallic noise but def wastegate flutter.

I can only think of the following possible cures: -

1. Change N75
2. Change DV
3. Change spring
4. Uprate spring (seems not recommended - shame as I have one and want faster spool)
5. Change wastegate (bigger/better/higher spec or just new?)

Cheers n

Si

[prj]

The reason for boost spikes etc is because boost is not mapped for the car.
Motronic boost control is a PI controller, if it flutters back and forth, then that means it is overshooting at start, then overcorrecting.
As simple as that.

If you fit a 1.9 bar spring on a setup designed for the stock 1.4 bar spring, and the chipset has no boost cut set, you will likely blow up your engine, because boost will rise over 2.5 bar.

Get a proper map.