Physics simulation - fixes with PL7.5
Yep, it's happening. First, a recap:
What changed with PL7
We fixed ‘Upgraded car loses’!
Even after the fix from early 2018, there were still cases where a more upgraded car could lose against a less upgraded version. The AI now drives more optimally, so an upgrade is always better than no upgrade (if you see different, let us know). This change also altered which tuning is best for some cars on some tracks, as previously a sub-optimal AI would mean a different tune had an advantage.
We fixed heavier cars winning hill climbs
Heavier cars were quicker up hills, which was incorrect. This is fixed, so now being lighter (by upgrading weight, or picking a lighter car) is an advantage in climbing a hill. As a knock-on effect, this made it more obvious that 4WD/performance-tire cars have too much traction vs 4WD/all-surface-tire cars.
We also made hills more realistic… maybe too realistic
Before PL7, the physics simulation effectively modelled the hills as significantly less steep than they appeared in game. This was fixed, so hills became as steep as they actually look, which is extremely steep compared to real-world roads - we’re talking gradients of 60%! This had the effect of some cars no longer being able to get up hills they used to be able to.
What is coming in PL7.5
As noted above, the fix to make heavier cars slower up hills revealed a long-standing but previously more hidden issue: 4WD PER/STD tire cars have too much traction, and 4WD OFF tire cars should have more traction, compared to 4WD All-Surface.
Cars with 4WD and PER/STD tires will now have less traction (with the exception of wet asphalt where 4WD/STD will get very slightly better)
Cars with 4WD and Off-road tires will now have more traction (with the exception of wet asphalt where 4WD/OFF will get very slightly worse, and gravel where 4W/OFF will not change)
The general rule is that the relative amount of traction you got with different tires on RWD cars will now be a lot more similar when comparing 4WD cars. For example, among RWD cars, those with Performance tires had a lot less traction than those with All-Surface tires, but among 4WD cars the difference was much smaller (and 4WD/PER was surprisingly competitive in off-road races as a result). Those 4WD/PER cars will now do worse off-road, as one would have expected.
Traction for all RWD and FWD cars is not changing. Also, traction for 4WD and All-surface tire cars is not changing.
Make hills less steep
We now think the ‘realistic hill’ change went too far, as many cars can no longer make it up hills, and that’s just less fun. Rather than remodelling the dioramas you see in-game to make them flatter, we’re adjusting the physics to treat them as less steep so more cars can make it up them (although still a bit more steep than they used to be).
What should change next?
Upgrade engine to upgrade traction?
Upgrading the engine currently slightly upgrades traction, but the game doesn’t communicate this, and the ‘Race Info’ tips will attribute this to ‘better spec’, which isn’t clear. This produces some strange results. For example, a stock 2016 Camaro Z/28 beats a stock 1970 El Camino SS 454 on the 1/4m on ice, but if the El Camino gets the engine upgraded to 1.3, this gives it enough extra traction to win, which you wouldn’t expect based on the 0-60 time. This effect also has an impact on tuning, making 969 a generally better tune for off-road vehicles, as it grants them more traction than 699. Should we keep this effect and communicate it better? Reduce its effectiveness? Remove it entirely? We really want to know what players think on this before we make any plans.
The differences between tunings on cars are often extremely small, and as a result the intuitive tunes do not always do best. With other major physics issues resolved, we can now consider changing this. We could make different tunes more viable, making for a more interesting late-game with fewer ties and more strategy, and also making the best tunes for each track more intuitive.
However, if we did do this then players with existing tuned cars would in most cases find they are less useful.
Such a change also needs to be considered alongside the above engine-upgrades-traction feature, as that would also alter the best tunes.
So, should we alter how tuning works? If it changes significantly, would we also have to enable a one-off ability to re-tune old cars so players could adapt their old garage to the new system? If we did that, how long should players have to do it, and could they re-tune multiple times? Again, we really want to know what players think about this.