My s4 manifold is cracked. And i just want to keep it stock and I heard the s5 manifolds are less prone to cracking.

To go from S4 to S5 all I need is the Turbo+Manifold+Exhaust Manifold. And it is a direct swap correct? Theres no Extra lines or anything?

 

How cracked is the manifold? Got any pictures?

 

all you need is the S5 turbo manifold and s5 turbo. Also cap off the Twin Scroll vac line.
Also what do you mean by crack? pics would help.

 

my s4 manifold was also cracked right now im trying to finish up my project and have the s5 manifold it bolted right up. Being that i took off the emission equipment i just never hooked up the twinscroll. i have heard people say that the manifolds should not be changed and i understand why. The different twinscroll setups. I believe it would be more noticable with running the s4 manifold on a s5 turbo. Being that the s5 manifold does not have the twinscroll i only see this as a loss the twinscroll feature on the s4 manifold. You may lose some low end but essential i believe it should work. Being that im pretty sure the ticking noise my turbo is making isnt good ill probably be upgrading it anyway. good luck hope someone has some more insight i am also interested in this topic.

 

It us my understanding the the s5 manifold is a superior design. Somthing about the engine pulses.

I went s5 turbo on my rebuild. I just combined my s4 coldside to an s5 hotside since my stock turbo was in great shape. It gives you the advantage of a bigger wastegate and better exhaust flow. If your turbo is good then try to find a blown s5 turbo and manifold. Use s5 heatsheilds as well.

If the twinscroll was so great why did mazda get rid of it?

 

Because the combination of a fully divided manifold and electronic boost control gave better results. That doesn't mean there was anything wrong with it. It did do exactly what it was designed to do, and still can.

 

Like there is a huge leak coming from the manifold and it seems to be getting worser everytime I run it hard.

I already have s5 turbo manifold and s5 turbo. and I can get a s5 exhaust manifold for like 60 bucks. So im just gonna replace all of it at the same time just to make sure.

So all i need to do is cap the twin scroll vac line?

 

^^Yes cap the twin scroll. I think you also have to use an s4 oil line.
While you have the s5 turbo off you might as well port it.

 

if u mean porting the wastegate. thats already been done.