The flapper delete was designed for people that totally delete the low side pcv and go vta.
DIY Low-side PCV installation (E89 Z4)
- Thread starter fmorelli
- Start date
So could I do this, instead of returning to the rear turbo inlet, could I just delete the flapper and run a line into my catch can and have a mini pod filer on the out of the catch can?
Okay, so there is no way around this then?
I still don’t understand what you mean then in relation to why a flapper delete exists? What situation would you use the delete fitting? How can you delete the flapper and not get the issues that I’m having?
sorry I’m such a moron and this is just not sinking into my brain.
Its better to ask then fuck up.
People go Vent to atmosphere aka vta to get rid of the low side on single turbo kits.
Thats what the fitting was made for originally.
But you can use it to externalise your high side but with a aftermarket flapper as the oem fail. If you wish to replace your oem flapper with a check valve then you have to use a vtt vacumm relief valve to allow a meter vacumm leak to the crank case they you have to adjust it to suit the motor needs.
Gets a little complicated for the novice.
Best is to reuse the factory flapper, its already set and you can forget about it.
People go Vent to atmosphere aka vta to get rid of the low side on single turbo kits.
Thats what the fitting was made for originally.
But you can use it to externalise your high side but with a aftermarket flapper as the oem fail. If you wish to replace your oem flapper with a check valve then you have to use a vtt vacumm relief valve to allow a meter vacumm leak to the crank case they you have to adjust it to suit the motor needs.
Gets a little complicated for the novice.
Best is to reuse the factory flapper, its already set and you can forget about it.
Thank you so much for answering and explaining everything for me i really appreciate it. I’ll find a way of installing the stock flapper in line.
thanks heaps,
Daniel
The flapper delete is used in systems that vent both the high and low sides to atmosphere. If you are running vacuum to either side, you will need the vacuum metering from the stock flapper and a low side valve. A vacuum break or vacuum relief valve is used as a metering valve that opens and allows air to enter the crankcase when too much vacuum is pulled on the crankcase, which is very easy to have happen when the factory orifices are modified or replaced. Stock vacuum levels in this motor are between 5-12in hg and if you modify your pcv system, it’s a very good idea to measure your crankcase vacuum afterwards so you can make sure that you stay within that range, and make adjustments if needed to get back within that range.
Thanks so much guys. I’m going to try and install the flapper in line with my current setup, I’ll just have to buy some AN-10 fittings that have one side that fits tightly into each side of the flapper valve and use some sealant make sure it holds pressure/ vacuum.
Really appreciate your help guys and explanation.
Legends
Really appreciate your help guys and explanation.
Legends
Looking to find out the direction of flow for the check valve that needs to be installed. Thanks
Can OP or anyone else tell me which direction the non return valve needs to face before the intake manifold? Does the arrow point towards the manifold or back towards the catch can? I’ve done the same install as having issues with 2D2E code and 30FF which I thought was because I wasn’t using a genuine PCV valve only a check valve but perhaps I have it facing the wrong way???
cheers
cheers
Which way does the arrow on the check valve face? Towards or away from the manifold?
Put your mouth on the valve and blow. The side your mouth is on when you can blow through the valve would be the side coming from the catch can, and the side you can’t blow through would be the side going to the intake manifold.
Remember, the valve is there to prevent charge air pressure from entering the crank case and to suck air from the crank case when the charge air is creating a vacuum.
Remember, the valve is there to prevent charge air pressure from entering the crank case and to suck air from the crank case when the charge air is creating a vacuum.
Damn, that is how I installed the valve, I thought the way someone explained it to me tonight was that it should be facing the other direction and thought hooray that’s the problem and it’s an easy fix but nope doesn’t sound like it... damn!
I will swap it out for a proper pcv like the 2jz pcv or if I can get the radium one delivered in a reasonable time that sounds like the best option, pricey especially due to Australia’s terrible exchange rate atm but that’s life, as long as it fixes my issues it just needs to be done.
thanks for your help guys
I will swap it out for a proper pcv like the 2jz pcv or if I can get the radium one delivered in a reasonable time that sounds like the best option, pricey especially due to Australia’s terrible exchange rate atm but that’s life, as long as it fixes my issues it just needs to be done.
thanks for your help guys
Hey guys so I think Iv fixed it, I just put the stock pcv valve inside the casing of the AN10 non return valve. I removed the spring and plug from the casing and had to grind the edges off the stock pcv valve so it’d fit in the casing of the new check valve then Took it for a spin and no more codes and drives great. I wasn’t hitting full boost but only off by less than 1psi on some pulls and 1-2psi on others and I’d say it’s because the stock valve is shot so I’ll buy a new one and chuck it in and hopefully will be hitting boost targets.
I need to upload my logs and get my tuner to take a look
thanks for your help guys
I need to upload my logs and get my tuner to take a look
thanks for your help guys
Shout-out to @fmorelli for this guide. 
I ended up sourcing a different catch can that came with 3/8 male fittings and drain valve, and got my aluminum fittings and check valve from RaceTronix. Parts list for those interested:
RB External PVC Adapter (same one used in this guide)
Generic Amazon Catch Can
-6an Bulkhead
-6an 90 degree female
-6an one way check valve
-6an straight push lock
I ended up sourcing a different catch can that came with 3/8 male fittings and drain valve, and got my aluminum fittings and check valve from RaceTronix. Parts list for those interested:
RB External PVC Adapter (same one used in this guide)
Generic Amazon Catch Can
-6an Bulkhead
-6an 90 degree female
-6an one way check valve
-6an straight push lock
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