As you do that, you reduce the contact patch, reducing grip.. and because you have an LSD, it power-understeers washing the front wide.
38PSI is too high. Try 34F 36R.
Geo maybe wants looking at, is it 'stock'?
What tyres do you have? a 225 is pretty small for all that power, they need to be grippy.
I think this is a combination of your style and possibly one or more of the above. I can't really tell you how to drive, but try this:
Enter a corner so that you turn in as you brake/lift, getting the weight to transfer to the front and increase grip. As you aim for the apex, gently start to trail the gas, you'll feel the diff hook up and pull you tighter to the line. Use this trailing power to drive you through the bend, only adding more gas as you wind the lock off and exit.