Ok guys - i'm looking at building my own exhaust manifold.

It's a 2.0 Zetec engine with a GT28RS turbo - it'll be of the 4 - 2 - 1 variety.

Thinking of about 1.5" primaries down to a collector, i'll be trying to 'pulse' the turbo by taking cylinders 1 and 4 together and 2 and 3 etc.

I don't really want long secondaries - and i'm not sure what sort of internal diameter to go for...

I'm thinking of building a turbo elbow to have two take offs, one as the main down pipe and one from the internal wastegate.

The wastegate pipe would go back into the main exhaust about 400-500mm further down to allow a nice shallow entry angle.

I'm thinking around 3" maybe 3.25" internal diameter for the main exhaust pipework and then i'll organise at the end...

For a power range of between 300-350bhp used for fast road and amateur drag - does this setup seem ok?

Also - any advice on secondaries would be appreciated.

 

Making it is the easy part, Stopping it cracking & lasting a length of time, is where the Knowledge comes in, even companies that do this type of thing can have problems on new designs.
Best leave well alone.