jmla

...

DanH

Yeah I'm not sure of wisdom of changing away from standard seal as it seems to perform better when there is no crankcase pressurisation. Is the problem that it might not maintain the vacuum when running?

HiWind

Hey Dan - did you ever do this one? I see a few' others' have per some of the lists you've made - not sure if the experience has been worth it? ie no leaks, slightly better dyno or just a wicked placebo effect?
PS - do I buy this from P or can I get it from the other/cheaper parts seller? Thanks again!

FFaust

DanH

nah I left it in the end. Not been using car huge amount of late and didn't want to do anything that might compromise reliability.

HiWind

fairnuf ... cheers

HiWind

Ordered mine - DHL as we speak. Anyone done this lately? Going to try the remove plenum and throttle body approach. Plug and play means pull of the old one and screw/clip this one back on? Any kind words of guidance appreciated as ever.

AudiOn19s

I don't want to be negative, but after tearing down my motor this past week to get the coolant fittings off to have them welded I have to say trying to change this crank breather from the top in the engine bay will be very difficult.

You need to take both center sections out of the intake off to make happen, it is going to challenge your patience none the less.

I had a tough time visualizing where this breather really was situated until I took mine apart. I stole Serge's picture here and added a pointer to show you were the breather sits. There's a large rubber line from the oil tank to the fitting when the oil tank is on the engine.

AudiOn19s

Here's one of his pictures with everythign still attached to the back of the motor

Number54

Crankcase breather seems not worth the potential unknowns.

I don't know why there is any performance gain here as crankcase breathers are really more of a reliability and emissions thing. I understand the RSR breather is more restrictive. Seems risky to increase pressure in there. For example, I installed an updated oil cap on my Audi - it has a pressure valve to prevent crankcase gas pressure affecting seals - the exact opposite of restricting the venting.

HiWind

Thanks for the pics audi - well made point!

cfjan

Bring this back to the top! Dropping the engine for coolant fitting welding in a couple of weeks. Debating whether this should go in or not.

Crankcase breather should work and free up some horsepower in theory. It is done on race bikes as well. So this is not something that only exclusive to Porsche. But will it cause leak. Seems to have conflict results based on the search on the forum...

JasonAndreas

I think there have been quite a few RMS revisions and additions since 2005? HERE are the latest installation instructions as a TSB for the 997 GT3. There is a similar TSB specifically for the 996 GT3 stating the same thing, "you must install the spacer ring" but it does not go into the same level of detail describing the seal installation (i.e. install backwards, etc.)

NXI20

Mine had it done 14,000 miles ago - it's a track slag & it's also had a 3.9 litre conversion so if it was going to leak, it would have done by now. It's dry as a bone. We used the 964 rear main seal as my engine builder rates these higher than any of the 996/997 seals.

cfjan

Any idea when was the TSB issued?

When I bought my car (back in '09?), the dealer performed a replacement for the RMS under CPO. It is completely dry since.

When chatting with the local shop (that will be performing the coolant fitting weld job), the consensus is that if it is not leaking, there's probably no reason to change the seals at the moment.