Chattering...

[ADU_S2]

@sal- keep up posted on what figures you get on the rollers mate goodluck!!

[sal_s2]

@sal- keep up posted on what figures you get on the rollers mate goodluck!!

Will do on Friday

[Jamo]

Where and what time/date are you having the car rollered mate?

[sal_s2]

Thor race engineering in coventry at 4pm. I've had mine done there before when it was standard so I can compare with my old figures

[S2central.net]

Yes I did the quick maths with the GT30 in mind and it looks good - also the GT35 for 2.5L conversions. Nuff said !

I'd like Mihnea to master the mapping on the GT series as thats what I have in mind 0 way down the line sometime...

[Doug_RS2]

if Mihnea gets good figures that mean that ur gonna be going for yet another upgrade

tempting i bet

it will be interesting to c what u get when mihnea finishes with urs

I doubt I will change - it is too much expense for little difference - I should be happy with mine when it is pushed a bit more. The turbo I have is good if you are after high end power and have the rods to run high power/torque at the redline.

[Jamo]

Thor race engineering in coventry at 4pm. I've had mine done there before when it was standard so I can compare with my old figures

Ah i think Sparkie mentioned they had a 4 wheel roller, can't wait to the see the plots.

[audiman]

More torque Doug, thats what you need. It has the power, now it needs the 'in the back of the seat' torque to suit. It should be evil once finished.

[Craig]

Chattering

Hi guys

Getting back to the subject of this thread. What causes that chattering sound?? My S2 does not sound like that, but I have heard it on a RS2.

Cheers
Craig

[Doug_RS2]

Metal piston diverter makes the sound along with lots of boost..

[Corey]

Sure you are not hearing the wastegate chatter? at high rpm it will be the wategate rather than the DV, the airbox muffles the noise of the wastegate. The sound you hear is the pressure wave going back through the engine, hence why the airbox muffles it. Remove it and fit a cone and wind up the boost, without the DV the noise is even more evident. It was quite deafening before I fitted the DV to the ur.

[dan_b]

The only change to the intake side of the car is this cone, and of course a remap on the turbo. The chattering/hissing/rushing noise is much more evident when you're booting it. If you're gentle, you can change gear without inducing any of this noise. I presume it's the wastegate letting off then? Is there anything that can be done to reduce/change the noise, other than putting the full airbox back on again?!

[Corey]

No, just sit back and enjoy the noise!!!

[audiman]

The noise you may be hearing is the WGFV venting excess air back into the air filter. Take the WGFV out of the MAF-Turbo hose and block the inlet into the hose off. This may get rid of the noise.

To me it sounds as if all you can hear is the turbo spooling up. Nothing wrong with that.

[GandalfS6]

If the sound you hear only occurs when you get off the power at boost, like when you change gears, it is the DV releasing boost. The DV's (diverter valve - not dump valve) function is to release boost when you get off the power to stop the turbo from stalling.

Normally you can't hear this if the car is not chipped and you are using a standard airbox. When the diverter valve releases boost it is released into the MAF to Turbo hose. Some of this air is sent back through the airbox (esp if you run higher boost) but if you use a cone filter this can heard - sometimes quite loudly!