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Hey guys! I have a 5.2 V10 with Twin GT35 Turbos and also swapped to the RS6 Intake manifold. I can't use the old PCV system so wanted to see if it was possible to install one from the RS6 5.0

Does anybody have the diagram with how it is routed off the intake manifold and back into the engine?

Hi there, I'm currently watching your YouTube videos on this project!

With this being an RS6 intake manifold (which has a dry sump oil system) fitted onto the S6 5.2L Block (a wet sump oil system), the PCV system for both is different enough that the entire RS6 specific PCV system won't just drop into the S6 block so you'll have to create a custom one, made from a mix of S6/RS6/Universal parts and probably some custom hosing.

On the RS6 the PCV is done by two items - a primary oil separator and a fine oil separator. The gases are initially sent from the engine rocker/valve covers to a RS6 specific primary oil separator which is built into the lid of the RS6's dry sump oil tank/reservoir (item 21 here - https://audi.7zap.com/en/rdw/audi+rs6+r ... 15-115000/) which takes most of the oil out first, leaving only a fine mist to be sorted out by the fine oil separator which also has the pressure regulator in it (item 25 here - https://audi.7zap.com/en/rdw/audi+rs6+r ... 03-103050/). I would guess that this fine separator is probably fairly universal in function (but expensive) and is therefore probably swappable if you add some custom hoses to make it fit, but that only does a small portion of the job at the end of the PCV chain and, for the RS6, it's that Primary separator built-in the dry sump reservoir that does most of the job, which doesn't help you at all I'm afraid.

Once the gases are oil-free, they're returned to the intake side of the turbos themselves to be re-burnt so you'd have to add a set of custom lines from the fine oil separator to your GT35's intake for that.

The pipework which links the inlet manifold & the LH/RH ports in the head to the fine oil separator on the RS6 is item 27 here - https://audi.7zap.com/en/rdw/audi+rs6+r ... 03-103050/ so you can possibly use something like that as a rough template for your custom PCV system.

Additionally, if you have a look at the RS6 Study Guide I've uploaded here - http://www.ianhenshall.com/C6_RS6_Study_Guide.pdf - on pages 18 & 19 there are images of the PCV system in its entirety there for you to have a look at.

I know it's not a full answer but hopefully it's enough to at least get you to a starting point and I look forward to seeing your videos on this project..................................Ian

The RS6 PCV uses non-return valves to direct the gases to either the turbo intakes (on-boost) or the inlet manifold (off-boost)

You're post are absolutely exactly what I've been looking for! Big big thank you for in helping me with what is essentially my last big hurdle! I have the 5.2 study guide, by the 5.0 is even better.

Just a shame it's all integrated into the dry sump system; ideally I'd like a system that seperates and drain back into the valley of the block, but seeing that there are no inlets for the turbos, I'm having a hard time picturing a way to vent under boost other than a catch can setup with a breather filter on it. I've found a few that commonly run on 1000+hp v8's so that may be the solution. I guess I just have to hope blow by insert excessive and that I remember to empty the tank every once in a while.

The RS6 fine oil separator is mounted on/in the RH valve cover (position marked here)

and drains collected oil into the engine via a crude flap valve when there's no pressure in the valve gear area. I wouldn't attempt to use it, I'd take a look at the non-separator valve setups used on other engines. The RS6 is the only turbo car that I've owned that has had such a complex vent system, all the others just dumped the fumes via non-return valves into the inlet down-stream of the turbos, often directly into the inlet manifold.

jolio1994 wrote: ↑

Sun Nov 05, 2023 6:34 am

I've found a few that commonly run on 1000+hp v8's so that may be the solution. I guess I just have to hope blow by insert excessive and that I remember to empty the tank every once in a while.

I think thats probably best. As Jim mentioned as well, there's just too much unusable stuff between the S6 and RS6 and something much simpler is going to be best and much easier to create/maintain afterwards.

I did a little more digging and spoke to Radium. This AOS will vent back into the engine under vacuum (idle and light cruising), but the vent out under boost. It requires a vacuum source pre turbo, but they said I could run a venturi bung in the downpipe to pull vacuum/evacuate blow by.

Vent to exhaust instead of the engine bay more or less. I can 1000% live with that. Thanks all who contributed!

https://www.radiumauto.com/Universal-Ai ... -P890.aspx