Vacuum exhaust cutouts

[09 L9H]

Does anybody here have any experience with vacuum-actuated cutouts? I'd like a cutout to a dump pipe in front of my center muffler but don't want to fool with an electronic one; it seems like they fail too often and I don't want a non-OEM looking switch in my dash. Opinions/experiences?

 

[kbuskill]

I've never used one but have been looking at them as well.

I haven't researched enough to know exactly how they work or how well.

My basic understanding is that they open up under hard, WOT, acceleration.

So I assume they are closed under vacuum and open when the vacuum is reduced.

My only question is... do they actually require boost to open up, like from a turbo???

 

[09 L9H]

I've never used one but have been looking at them as well.

I haven't researched enough to know exactly how they work or how well.

My basic understanding is that they open up under hard, WOT, acceleration.

So I assume they are closed under vacuum and open when the vacuum is reduced.

My only question is... do they actually require boost to open up, like from a turbo???

This is my understanding as well. They say you have to run a vacuum reference line for it to actuate, but where do you run it to? Corvettes have vacuum cutouts from the factory so you don't need FI, but I'm still not completely sure how it's all plumbed.

 

[Ilikemtb999]

They make both vacuum and boost actuated ones.

A friend has a boost one installed on his turbo caprice. Seems to work.

https://loudvalves.com/collections/vacuum-activated-loudvalves

 

[justinesky]

Iv been thinking about these too. Is there really any power to be made here?

 

[iamdub]

This is my understanding as well. They say you have to run a vacuum reference line for it to actuate, but where do you run it to? Corvettes have vacuum cutouts from the factory so you don't need FI, but I'm still not completely sure how it's all plumbed.

The intake manifold is where you'll find vacuum. I'm sure there's a convenient port somewhere on the manifold itself or you can tap into the brake booster hose. You'll just need a "T" that has the straight-through part the correct size to go inside the booster hose and the port out the correct size for the hose going to the cutout. Pretty simple.

The fitting would look something like this:

 

[kbuskill]

Iv been thinking about these too. Is there really any power to be made here?

No.. probably not... it's more for the sound/cool factor.