According to the documentation, both the 2.0 and 2.5 water-cooled B4 swaps for the Piccolina are from the Hirochi SBR4. As in the Sunburst, the sounds differ between the 2.0 and 2.5 (and are the same for both the SBR4 and Sunburst), but both of these engines use the "classic B4" sound when installed in the Piccolina. Also, although I realize this request is out there, would it be feasible to add an optional pitch multiplier to the combustion engine code that can be specified in the JBeam? I don't see any vanilla vehicles that would benefit from this functionality at the moment, but with the difficulty of sourcing mod engine sounds and the limited functionality of mod engine blends, this alternative approach definitely has its use cases. The reason I'm suggesting this for vanilla instead of just making my own copy of the combustion engine Lua (as in the video) comes down to simplicity and flexibility for mods; otherwise, every separate mod would need its own altered copy of the combustion engine Lua with no substantial differences other than the pitch multiplier, and on top of that, a multiplier specified via jbeamData would allow for parts like headers to affect the pitch (just as they can already overwrite sound sample references) rather than requiring a whole different powertrain device to be specified in the core engine part. Again, I know this is far from guaranteed, but I had to try.
Just watched this and your previous sound-mixing videos, and I'm glad you did this because I wanted to try this but I don't know the first thing about coding. I first had the idea when Agent_Y first released the sound sample selector for this mod way back in 2020 (was it really that long ago?)