Obviously not everyone can do this at home but somemay find it useful
I had a customers SR20 FWD Race car in for some turbo work… They had bought a gt28 from ATP… ATP claims the GT28 fits with the stock manifold near the tranny. Not so. The tranny bolt interferes with the intake of the turbo compressor… you can’t fit an intake on the turbo.
A solution
I made a flange for the inside of the turbo to fit a cone out to 3". the compressor wheel is 2" roughly.
