It's the blue pipe just above 18 on the diagram.

Thanks for that, much appreciated to all that helped .

I can see why it was mucking around !

Never seen one that bad before.

Never seen one that bad before.

I was quite shocked at how bad it was actually.

you can get uprated aftermarket pipes to replace that lot few on e bay

Never seen one that bad before.

I have

Like I said, as you have to take a lot of bits off to get at the area under the manifold it make sense to do all the crank breather pipes and the suction jet pump. Don't forget to include a handful of the metal check valves and you will have full boost again