I am planning to do a sti shortblock swap on my 04 wrx and I was wondering if ran a bigger turbo lets say fp green or gt30. Would my tranny be able to hold it?

 

how many miles are on the tranny?

the question is not if, its when on those transmissions. I went through 1 manual and 2 automatics.

If you can get the 6 speed do it, the problem lies in case flex.

Dog boxes for your existing case are expensive, but they are basically indestructible.

The problems you will find with the 5 speed is shift forks, 2nd gear, and syncros all get destroyed by horsepower. Add a strong clutch and you might as well just save up for a rebuild.