The diff would be my first mod if I did it all over again.
Not purely a traction issue, it transforms the whole dynamics of the chassis.
The entire cornering/balance of the chassis is affected in such a positive way.
Its a totally safer, more predicatable animal. An extra 100bhp wont cut your circuit times much compared to fixing the chassis first.
So on the road its just the same thing unless you are a simple drag racer.
An open diff WILL NOT put down all your output on the road out of a corner.
You may get away with it in a straightline, but you are backing off on the exits of bends I guarantee you.
Anyone who has done a few track days will tell you - the last thing on your shopping list for a road car is going to be more power.
Nobody likes to admit it though because an LSD
1. Is not shiny
2. Is expensive compared to software
3. Doesnt make your traffic light grand prix more exiting
4. Doesn't give you BHP / TORQUE bragging rights in the pub
What it DOES do though is make you quicker everywhere. So long as you can drive.
