Can someone explain the MK7.5 and 7.5’s pcv magic?

[PRRGG1]

 

[Keehs360]

Typically talking about big turbos running 30ish psi or more, but guys with bigger turbos would be a better resource for that info, I'm tracking the car on the stock turbo and stg 1.

Thanks for the info!

I plan on tracking with stage 1, stage 1 dsg, intercooler

I’ve been tracking with my wrx this past spring and summer and it’s been a blast! 5th fastest stock turbo wrx at high plains

any opinion on intercoolers would be appreciated if u can spare the time

 

[Keehs360]

View attachment 190128

Bro. End thread. This is it thanks so much!

damn it really is an air oil separator. Why the hell would anyone remove this in favor of a catch can?! I’d understand putting a catch can in line with this AoS. But deleting this wouldn’t be a great move.

 

[StorableComa]

Because a bigger air oil separator must mean more winning? This thing is so wimpy wimpy, CCs are Hefty Hefty.

 

[Keehs360]

Because a bigger air oil separator must mean more winning? This thing is so wimpy wimpy, CCs are Hefty Hefty.

Im from subaru land, and i have installed my share of air oil separators. even the crappy cheap small ones are solid as hell. my neighbor built a ej257 bug eye just for the track and he went with an air oil separator that pumps in the baffled air into a catch can and back into the motor and turbo ccv. just for insurance, yet even after almost three years the catch can stays clean.

we did go with an aos that pumps in and flows radiator fluid on the exterior and back to the radiator. this keeps the aos warm and it handles condensation.

 

[StorableComa]

On the MK7, unless driven pretty aggressively on a track - CCs tend to stay clean unless they delete the whole PVC system. Then they see use as they're acting as the PVC. MK6s on the other hand, had crappy factory PVC and you could empty out a CC every couple weeks with long miles and street driving.

 

[jimlloyd40]

The Spulen OCC still functions the same just diverting the liquid to the catch can.

Because you removed the pcv.

 

[StorableComa]

Though if you're driving hard, you're more than likely doing early/pre-emptive oil changes anyhow. So what is the issue with letting the liquid go through the oil return?

 

[jimlloyd40]

Just go water meth, then you'll get a nice mist over your valves and won't have to worry about buildup. At least that was the logic on the MK6, but the stock PCV sucked on the MK6 so you options were water meth or CC.

Isn't the water/meth only getting injected at a certain throttle input?

 

[StorableComa]

Isn't the water/meth only getting injected at a certain throttle input?

Depends. I haven't looked into it very much on the MK7. On the MK6 you could get boost dependent controllers.

 

[StorableComa]

Though even if it's only partial use under higher boost, it's still misting over the back of the valves. Depending if you do charge pipe injection. Which helps clean them better than any CC I believe would.

Edit: quick google and I Found this:
https://www.uspmotorsports.com/MK7-GTI-Water-Methanol-Injection-Kit.html
Looks like boost dependent and it's intake track injection.

 

[Keehs360]

On the MK7, unless driven pretty aggressively on a track - CCs tend to stay clean unless they delete the whole PVC system. Then they see use as they're acting as the PVC. MK6s on the other hand, had crappy factory PVC and you could empty out a CC every couple weeks with long miles and street driving.

Yeah I’ve heard

 

[jimlloyd40]

Though even if it's only partial use under higher boost, it's still misting over the back of the valves. Depending if you do charge pipe injection. Which helps clean them better than any CC I believe would.

Edit: quick google and I Found this:
https://www.uspmotorsports.com/MK7-GTI-Water-Methanol-Injection-Kit.html
Looks like boost dependent and it's intake track injection.

How would that help keep the back side of the valves clean?

 

[StorableComa]

How would that help keep the back side of the valves clean?

Because it's being sprayed before the intake valves, when the valves open, they pull in the mist from the intake. Anything that condenses on the back of the valves gets pulled in..

 

[Keehs360]

Though if you're driving hard, you're more than likely doing early/pre-emptive oil changes anyhow. So what is the issue with letting the liquid go through the oil return?

I dunno. The oil that drains back to the engine will look like a chocolate milkshake. It’ll be unspent fuel mixed with condensation and oil. People say they don’t want that nasty stuff back in their oil pan. But that’s dumb

if your oil is up to temp it’ll burn all that off the second it drops and recirculates back in.