I can tell you how to set up the speed 12 to almost totally eliminate wheelscreech, give it perfect handling, and improve speed, but with the same power. To get it do as follows:
APPLY NO POWER UPGRADES WHATSOEVER, EXCEPT MAYBE NOS & OIL CHANGE.
Brake balance controller - set to 24 - 24
NOS - set to max (70 i think)
Racing suspension - set to,
Ride height - lowest.
Camber (whatever the one next down from ride height is) set to 2.
Toe angle set to 1.0 - 1.0
Stabilizer set to 7 - 7
Race transmission set to,
auto setting - 10
set gears 1,2,and 3 to 1/4 of bar from left.
race clutch, triple flywheel.
LSD (very important - eliminates wheelspin) don't adjust it at all.
Racing R5 tyres (super soft/qualifying)
Oil change
Rear spoiler - set downforce to max front & back.
Voila! now your blackpool beast should be amaingly good.
For example - i can do nurburgring in roughly 7 minutes with totally stock speed 12.
With these upgrades - 6:03.
(one final note - be sure to still brake early - it is still a tvr remember
)