$1,000 won't buy you any performance for the X5. I'm not being snide; I'm serious. Come to think of it, $5,000 won't buy you any performance. Ok, maybe you can spend $8,000 and get all the Dinan kit - which will net you something like 30hp to the crank - so, about, 20 to the wheels. That's $400 per horsepower that you won't even feel because the truck is too heavy for 20hp to make a difference.

Spend the $1,000 on maintenance, preventative maintenance, any plastic trim pieces or clips that need replacing, minor body imperfection correction, etc.