What do you guys buy when replacing your bad bypass valve?

Better stick Mini or OE?

 

I went with a Detroit Tuned BPV on my MC40. It's marketed as slightly more efficient due to a higher precision build. Did it make a difference? No idea since it's very difficult to qualify or quantify. There are many other mods that probably make more sense.

 

on R53s is this BPV considered maintenance item? mine right now is okay no YOYO effect, no stumbling, no hesitation. I heard that the last BPV version got updated by MINI,since then no more issues with the spring breaking.

PN: 11617568423

 

I would not consider it a maintenance item as it's not a wear & tear part.

 

I also replaced mine with the detroit tuned one a while back when I did a bunch of maintenance . I did feel some better response but I did also notice that my yo-yo effect became more pronounced on my 2004
perhaps another undelying issue with my car , but that was the experience i had .

 

so the yoyo did not fix the issue?

I was observing mine yesterday, I noticed as soon as the engine turns ON - ( running ) the BPV's rod moves inwards which means it's OPEN now when I press the gas pedal for say up to 3500 rpms it stays there it's not moving did not close. It only returns back to close when the engine is OFF

So if this BPV is always OPEN at any RPM range that means I have no BOOST, air goes directly to the intake manifold the metal one that's under the SC radiator.

So in short I am driving an R50 mini!!! it became an NA 1.6 engine. If this is the case I will leave that BPV like for now, atleast it's not loading my SC, less stress on the engine.


it does not do this like the one on this video. It stays open, no movements it will only move when you turn off the engine.

BPV - Open and close action

 

any other aftermarket recommendations aside DT BPV?

 

When you move the rod from the valve by hand, do you feel resistance?

The bpv itself doesn't nessesarily have to be the problem. What you describe is not the yoyo effect, which would happen around 2500rpm while cruising.

As for your question; in the UK there is a guy which make the valve seal perfect (so the valve doesn't leak boost) and puts in a stronger spring. That guy is known as Rooster Racing if memory serves me right.

 

There's a resistance, like when I push it towards the diaphragm chassis then release - the rod comes back to close.

I got no issues between 2000 to 3200 I always stay there when cruising maybe 2000 to 2600

 

It's my understanding that Detroit Tuned simply takes a stock BPV and repositions the valve flap for a better seal and installs a heavier spring -- not exactly rocket science so the efficacy may or may not be in everyone's mind only. I have read posts where larger BPVs (off other vehicles) producing more air volume were installed. You might research that angle but then more air would also require larger injectors and a related tune. It all depends on what your HP goal is. You're dealing with a small 1.6L supercharged engine that will cost you $10,000-$12,000 to achieve 300HP and even then may not be reliable. This is the reason that so many look to swap a Honda engine into their Mini -- cheaper parts, more HP potential with a turbo.

 

Been reading NAM about these MIni factory BPVs, almost all here say that the MINI BPV always come with gap ( not really sealed, closed ), it is closing but there's a gap. A lot here are adjusting the screw to close it.

If Mini is selling them like that there's probably a good reason why there's a GAP.

This is the reason why I asked here.... is it better for me to buy MINI BPV or some third party OE that are closed\sealed?

 

Yeah it won't close when revving at standstill unless you basically floor it.

 

Do you know when will this BPV closes? at what RPM?

 

It's vacuum controlled, it's not tied to a certain RPM. Vacuum in the intake keeps it open. When you accelerate with enough throttle opening for the vacuum to drop, it closes.

If you suspect that the BPV is not closing at all, plug in a Scangauge or some other OBD2 scanner and observe the boost levels while driving. Or temporarily zip tie the PBV shut and see if it makes a difference at WOT. This may cause a bit of yo-yo at small throttle angles tho.