Ask HN: Where to collab on building automative circuit/software mods?

I'm hoping to find an online community of devs/engineers that share work on hacking their car's OEM electronics across many vehicle brands.

Many small communities share aftermarket circuits (e.g. wranglerforums, tacomaworld, autohack, yodaTeq...), but I can't seem to find a good source for sharing work on building those circuits or sharing the source code.

Types of things I'd like to do:

- Adjust control software of various sensors in the car

- Put optional settings always-on/off (engine-shut-off-when-stopped, adaptive cruise, ECT power, all-wheel-power)

- Adjust the electronic transmission shift points

- Adjust the algorithm for shutting down cylinders