a properly matched converter is prolly the single best improvement you can make on a turbo car......if you stick with a 12" (stock) converter, then 3,000 is about max stall....the 9.5" can stall wherever you want
with a good converter, stall up to 3600 or so is transparent when driving the car on the street.....but, when you get serious about going fast from a stop, you will definitely notice the difference...as Bruce said, you better have sticky tires or all you'll have is smoke.....and worn out tires
spend your $$ on a good converter long before a cam.......