I thought that the GT3071R actually needed a .82 exhaust housing and that the .72 3 bolt Cosworth type would not be so great. But I guess that converting the exhaust to a V band isn’t that difficult.

A few years ago I looked into a GT28, as it should spool better than a T34 but still get the same power. I always find it strange that it seems there is no one who wants good spool with about 400 bhp. All popular upgrades, like the GT3071R and EFR7064 go close to 500 bhp and need the gearbox to be upgraded as well, at least on a 4x4.