Fast path help needed

I understand when setting a fast path in the AIW that it has to be fast to a certain extent but if anything smooth.

I've read from some posts that it can be slow & fast as you like as the AI adjust it themselves. I have a couple of questions.

Can I ask what cars people use to set the fast path?

Is that correct that a lap can been extremely slow?

I can't seem to drive the Skipbarber & have been using an LMP1 which I'm questioning whether it's the car I should be using.

Any advice appreciated.

Thanks

 

I use Apex Modding Ferrari GT3 and it gives pretty good results.

 

I use our F3 Mod with increased Tire Grip and an Engine with less Power.
In the End, it doesn't matters which Car you use as long as you can drive smooth and exact Lines with it.
And it is right, that you don't have to drive the fast Path by driving at the Limit as fast as you can.