The SPA manifold is a good part. I like to have it machined to accept a T4 turbo flange. They are made for a T3 flange. There are very few T3 turbo choices that use a remote wastegate. And the T3 cannot move as much exhaust volume.
The T4 can normally be had with remote WG and come with a much wider array of exh housing sizes.
SPA will not ( as of now) machine the manifolds with a T4 flange. I used to sell them. They're casting is setup for a T3 flange. The ones sold on ebay with a T4 flange are welded up T3 and remachined to a T4.
