bweSteve

Hey Mark,... like you,... since I had not heard of this before (albeit I have only owned my 2010 GT3 for 10 months),... I called my local SA and asked about this. It only applies to the RS, not the regular GT3 (in the 997 series).

I agree that it is odd that the pinned lines gets more promotion / discussion verses this issue. Wow, so sorry to hear you (OP dt8) have a total engine failure as a result.... ESPECIALLY given the WC-512 campaign had already been executed on your car. damn that sucks.

Does this mean that ALL replacement WC-512 resonance tubes / intake flappers are susceptible to degradation over more years & miles? ... seems like it might be a good idea to replace on a regular basis, and even have a spare on stand-by if you notice any cracking etc. Should be an easy replacement DIY right?

=Steve

sl951

How many people had this fixed on their .2RS?

74goldtarga

Can someone upload an image of this? It might be useful to know exactly where the part is and what it looks like (for those of us previously ignorant of this issue), and ideally what it looks like if it cracks or fails. The 3.6 engine is a different part? What's the difference?

Also, to the OP - sorry about the bad luck with the engine.

FLT6SPD

This was more of an issue for the 4.0, not really a known failure for the 3.8 maybe changed proactively.

The screws that hold the flaps would loosen and get inhailed

CRex

There's a known failure in HKG with a 3.8... WC51 campaign completed, but the butterfly screws still disintegrated.

Engine had to be rebuilt... no warranty coverage. I don't know if there's a smart way to prevent this and am a bit peeved myself... loctite on the butterfly screws perhaps? Smart ideas appreciated...

skafia

Excuse my ignorance but are these recall campaigns, or just normal maintenance items?

Thanks in advance.

CRex

^ Service campaigns, worldwide.

nle

Looking into this issue again, are those problematic screws not the same two screws on the throttle body butterfly valve? Or are they actually way inside the actual manifold?

If it’s just the throttle body butterfly screws, they can be easily tighten by removing the airbox. please enlighten me.

powdrhound

No. It's an engine out affair as the whole intake distributor (pictured in post #19 above) needs to be removed from the intake manifold which is bolted to the heads. The intake distributor then need to be disassembled so the center section can be removed and the internal flapper valves accessed. Everything can then be reassembled with new gaskets and remounted on the engine. This is a perfect opportunity to pin/wend the coolant pipes as then engine will be out.

bonehead

There's a massive thread on engine harmonics and the damper sold by one of the vendors here that explains what exactly fails (and what they think the failure mode is)

Here's the thread: https://rennlist.com/forums/997-gt2-...cking-out.html

nle

A lot of us on here run Dundon’s harmonic balancer which helps with the cam bolts. This issue w the resonance tube is different and seems more uncommon with the intake flap bolt dropping into the motor.

prl

Can the flappers just be removed? Or can I 3d metal print a new center without the flappers?
With no need for a tune?

Auto_Werks 3.6

you do not want to remove any flaps from a variable intake plenum. This is how the factory improves torque at low RPM while keeping good top end power. You will be displeased with the results. If you’re going to do that, see about a dundon intake manifold… not cheap at all, but all the rest of their stuff has really worked for for me

vma1788

Is that true? Dundon intake manifold does not run these flaps. However you do need to tune for this.

Subarus have/had a similar design, called TGVs, which was common to delete back in the day with my 05 sti.

Spyerx

You can run the cup intake… the flappers on the intake help midrange and low. Tune won’t be enough.

Subarus have turbos, not N/A motors, so very different, you don’t get the benefit of boost.