Rajay Turbo?

I honestly do not know how effecient they were. I have a friend that has one on a 413 that came from a motorhome as well. The fuel passes through the turbo. Seems like it would cause problems with the oiling of the turbo. His is a Gale Banks setup with the spacer under the carb that has 2 tubes attached. One pulls through the carb and to the turbo and then back into the spacer and into the intake. Garbage in my opinion. Or should I say not for performance applications.