I’ve just swapped my manifold for a stainless one from cobalt (thanking @Blip1 for providing it!), and now my question is around heatshields.
The original one mounts using nuts welded onto the pipes, no chance of doing the same here - and it’s pretty rusty anyway. I’ve ran it hard on the motorway for a bit and while it turned gold from the heat, nothing else melted or set on fire!
The original also had heatshields leading all the way down the the cat, is this a concern as the new stainless one has nothing?
I’m thinking to bend a sheet of stainless and mount it in the engine bay, just to protect the airbox and washer fluid box, but I’m keen to get others opinions
I hear wrapping it is a bad idea because of the inevitable corrosion, and I do like how it looks bare at the moment…
The gold colour is normal. Depending on a number of factors other colours may emerge and evolve too.
I don’t know whether the manifold can be polished back to bright silver. I’ve never tried.
This was mine shortly after fitting.
This is today.
The spots are from water dripping on to the manifold from above through louvres I’ve fitted in my bonnet.
Passivation (a bit like bluing) at work. Probably had a coating of a light oil. The oil reacts with the stainless steel when hot, to form a layer. Different colour effects achieved with different oils. Its a one time effect.
Fingermarks can also last forever if the manifold isn’t alcohol cleaned the first time after running.
