So I decided to test the effects boost has on the car and work out how exactly it makes you quicker to compare to how cars handle with bugged physics. For this
@zzz_pt and
@RA1784 helped me out, zzz_pt for actually testing the boost (need a car in front) and RA for comparing the handling with boost and RH tyres and the handling with RSS without boost to the handling of the car when his physics were bugged.
With zzz_pt we were using Gr.4 BoP Meganes at Bathurst with RHs and with RA we had maxed out Gr.3 Porsches at Dragon Trail.
The effects of boost (on weak);
- Much better traction, can put the throttle down much earlier and your car sort of gets dragged around the corner. (similar to bugged laps)
- Despite the better exits there was no noticeable gain in straight line speed according to the speedo however even though we were doing the same speed I was still gaining a massive amount on the straights in boost. I calculated that I was actually averaging 149mph on one of the straights in boost when my speedo average was 141mph. (bugged laps don't see any gain in straight line speed even with better exits as mentioned before, just like boost, but bugged laps don't have mysterious time gain even when doing the same speed like with boost)
- No significant gain under braking reviewing my laps, maybe a slight improvement braking a bit later and slowing to a slower speed but I wouldn't say as noticeable as with the bugged laps. Not sure if @zzz_pt agrees. This could be explained by the actual speed being higher than what the speedo says when under boost, so you're actually approaching the corner faster and braking at a similar point to without boost.
- No noticeable gain in cornering speed, but we weren't driving as well with boost as without and again this might be explained by the speedo speed being less than actual.
- And of course a massive improvement on lap time, nearly 10 seconds, which is much more than the time gained with the bug (around 3 seconds).
@RA1784's verdict was that the handling of the Porsche when his game was bugged was close to how it felt whilst boosted and on RH tyres as opposed to when he was driving without boost and on RSS tyres.
So if you were to give a car the handling characteristics only of boost and none of magical time gain stuff, i.e. speedo speed = actual, then the resulting effect could quite possibly make your car handle in a very similar way to as if it was bugged. Giving the driver unrealistic traction, not increasing their straight line speed even with significantly improved exit speeds, and potentially increasing their cornering speed and allowing them to brake later when the speedo is reading the correct speed and they aren't approaching corners faster than usual. As for the resultant lap times, it would obviously be less than 10 seconds without magic time gained down the straights, but it's difficult to know exactly how much handling characteristics alone are worth.
This doesn't really answer many questions but it is interesting to see the similarities between the effects of boost and the bugged physics so could offer some insight into the cause of the extra grip. It still doesn't explain how boost would remotely effect sport mode practice, or why
@RA1784's settings reset all the time, but hopefully this might be useful in some way.
EDIT: Forgot to mention we also proved that boost is really bugged anyway in custom lobbies. Not only does it work in practice somehow and not just in races, even after I had switched it off, the first timed lap would have boost if no one had left the pits later than you (zzz_pt joined the track after me and my grip immediately got worse) but even after he had left the lobby and rejoined he still was boosted for his first timed lap.