Yes. Now you have left a few things out have you altered the ai files or added any updates to the tracks? What version of Bristol are you running there are a number of them out there.
You can run the orginal Bristol offline for a 100 lap run without a caution,it can happen.
lol ive tried to run just about every bristol track out there that i can find...it all does the same. i even deleted all my bristol tracks and re downloaded them. the problem seems to be not as much of the cars running into each other, as much as it is the cars trying to merge into one line, even if there are cars to the outside of the merging car.
The ai don't sort themselves out very well at the short tracks.
I've used these things to help:
Decrease the ai_pacing distance a little.Will help tighten the field up
some so they're not slowing in the corner as much.
Lower the ai_dlongpad_scale to 0.30.This should help them get closer
without rear ending as much.
Increase the ai_decel_modifier some.Should also help them get slowed
under caution a little better.
I've never messed with the pace car exit because I got these to work fairly well,
but there is a line that also might keep the pace car on the apron a little longer.
Not 100% which one it is though.lol
The trick is to make fiield have gap between the cars
Try these
ai_wall_offset = 30 ; 100 = full-time AI collision detection
ai_tire_wear_left = 1.18 ; left tire wear adjuster for ai
ai_tire_wear_right = 1.24 ; right tire wear adjuster for ai
This way the car slow to save thier tryes
chnage the wall offset stop the car running into each other