[SpoolMan]

If you had no wheel spin with a 2.5, 60 foot time, you need something to get you out of the hole in a real hurry.
With 105mph it looks like you have decent amount of power, you need to get the revs up a lot more when leaving the line, get the power in more swiftly a Hi Stall would help there.
Not sure how big you can go before you have problems with the limp home mode.
You are going to need both diff and Hi Stall, and then more than likely you well need good tyres.
Question I have is what revs you stalling to when are leaving the line?
Do sit and spool the turbo right up before you leave the line?
When you get your 60 foot time right, your cars times are going to tumble.
105 mph suggests your car has much potential.