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And I am not comparing stefan PCB with mine, I am comparing GameCenter PCB (see the video) with versions of mame 106 and 147!!!

Of course, what we should be comparing is the PCB from which the dump in MAME came from...

Let's talk technically:

Generally, an arcade PCB speed is controlled by a vblank irq, this is the event that signals when a given screen h/v beams transitions between the right-bottom to the left-top (basically, the end of a single frame). This is NOT the case of Hot Chase, according to the available schematics there are two irqs. One is tied to the aforementioned vblank, the other one is tied to a custom chip. This custom chip is widely used by several Konami games of that era (for example WEC Le Mans, that is a very similar HW), and it's a scanline-timed one (i.e: trigger every 32 or 64 scanlines). For the very specific example of Hot Chase it's NOT written in the schematics the exact timing of that one, just guessed it out to be the same as WEC.

Bottom line: The driver itself is full of imperfections and not known behaviours in a HW perspective (not only the aforementioned, but also video/sound issues and many system bits not understood), there are questions that only PCB tests could answer (and I actually fear the fact that it uses mask ROMs, but that's another story).
I take into account that it doesn't work with current implementation if there are other bugs other than the speed itself. I still don't think that the speed was right in 0.106, regardless.

So, it was actually a different issue, was actually looking at video but of course sometimes happens that sound could take some time too if handled incorrectly (details at my blog). Therefore I guess that upcoming 0.168 version is the real deal for this game.