Nissan Z Blow-Off Valves

HKS is a the crowd favorite for the VR30. I like it as well, though may use a Tial setup instead.

BOVs are, in my opinion, necessary for the VR30 as it doesn't come with any kind of BOV or re-circulation system from factory (from what I recall).

because_murica said:

BOVs are, in my opinion, necessary for the VR30 as it doesn't come with any kind of BOV or re-circulation system from factory (from what I recall).

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I actually wasnt aware of this as I always just assumed they were recirculated like the VR38.

MCN1SMO said:

I actually wasnt aware of this as I always just assumed they were recirculated like the VR38.

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It should absolutely be that way from the factory, yes. But, if memory serves, unfortunately, the VR30 has no re-circulation system. So, once you left off the gas, that boost pressure goes back to the turbine wheels - not good for longevity.

From what I've read on the Q forums, the way the VR30 deals with boost pressure release is having the throttle plate & wastegate close progressively and stay slightly open upon removing throttle input until the pressure is released. This would work (although I think it's pretty silly engineering when recirc valves exist) to prevent extra wear on the compressor wheels, but a few people have said that they have almost gotten in accidents due to the car not instantly cutting power if they needed to quickly react on the brakes from a state of having the throttle mostly open

Metal said:

From what I've read on the Q forums, the way the VR30 deals with boost pressure release is having the throttle plate & wastegate close progressively and stay slightly open upon removing throttle input until the pressure is released. This would work (although I think it's pretty silly engineering when recirc valves exist) to prevent extra wear on the compressor wheels, but a few people have said that they have almost gotten in accidents due to the car not instantly cutting power if they needed to quickly react on the brakes from a state of having the throttle mostly open

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That's pretty wild. One of the benefits of a manual transmission, just kick that clutch in.

because_murica said:

That's pretty wild. One of the benefits of a manual transmission, just kick that clutch in.

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Right, I'm going to get a manual anyways, and I think I'm gonna get BOV's just because I've always wanted the wooshy air noises. A big topic of debate is whether or not you need to get a tune after installing them because the VR30 uses a MAF

Metal said:

Right, I'm going to get a manual anyways, and I think I'm gonna get BOV's just because I've always wanted the wooshy air noises. A big topic of debate is whether or not you need to get a tune after installing them because the VR30 uses a MAF

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+1

Metal said:

Right, I'm going to get a manual anyways, and I think I'm gonna get BOV's just because I've always wanted the wooshy air noises. A big topic of debate is whether or not you need to get a tune after installing them because the VR30 uses a MAF

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because_murica said:

+1

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Who doesn't love a good wooosh once and a while 🤣

because_murica said:

HKS is a the crowd favorite for the VR30. I like it as well, though may use a Tial setup instead.

BOVs are, in my opinion, necessary for the VR30 as it doesn't come with any kind of BOV or re-circulation system from factory (from what I recall).

Click to expand...

Are there other ones that work well with the engine or HKS the way to go?

Concept Z performance sells a kit with the Turbosmart Vee port BOV's and a couple Q owners have them and have said they're a bit "smoother/more subtle" sounding compared to the HKS.