"You've got an LSD, right?"
You have a limited slip differential, right? (It helps put power to the pavement more efficiently.) Without LSD, you're going to have a hell of a time accelerating out of those corners.
"She's too rich"
In the process of modifying the car and making sure everything's adjusted properly, the air-to-fuel mixture got a little out of balance. I'll spare the stoichiometry-speak, but "too" rich means there's more fuel going into the cylinder than there should be.
"She's too lean"
This is simply the inverse of being too rich.