If I have to over-rev it to get it going, then I'm losing any mpg gains I may have had by fitting it in the first place.
When the JDD 'box was first introduced as a concept, I played devil's advocate and argued that it wasn't a very good idea, even though I wanted to see someone go ahead with it and make it work. After all, I like to see new options pioneered.
Whilst it does work, and provides a relaxed, efficient way of doing longer distances, I remain sceptical, for reasons noted in the posts above...
I'll rev to 4k and it'll drop to spot on 2k in most gears
The idea of rev'ing a cold engine to 4000rpm pains me. I'll take my TDI120 to 4000rpm when I'm having fun with it, but only once everything has been given a chance to get up to full temperature. On a winter morning, when the TDI can sound like a tin can of spanners, having to rev to 4000rpm just to get into the next gear isn't something I'd enjoy doing.
MPG definitely takes a hit using that longer power band but can still get the revs super low for those longer trips. still average a reported 59-60mpg in mine.
We're obviously comparing apples with oranges here, because your use of your car isn't the same as my use of my car, but I average circa 73mpg with my 6-speed 'box. That's not just 2 or 3mpg difference but a whopping 10-15mpg more. Yes, I probably do more motorway miles, but it'll also be due to me having a suitable gear for every scenario, and not having to rev to 4000rpm all the time. The JDD 'box results in zero gearing flexibility, plenty of scenarios where the engine is rev'ing high or conversely spluttering a little, etc. In urban environments and awkward country lanes, I find it really tiresome to have to manage the huge jumps between the gears. Admittedly, my first-hand experience of driving a JDD-equipped A2 is limited to a few journeys.
I will also occasionally double de-clutch to smooth things out
I double de-clutch with every gear change no matter what I'm driving; it's a totally engrained habit and it feels weird to me to just move the gear stick from one cog to another. The other advantage to this technique is that the 'blipping' of the accelerator pedal whilst in neutral keeps the revs up and keeps the turbo spinning.
I think you are looking for the impossible Kaz ... I do not think the polo map will make any difference
I'm inclined to agree that there is no perfect solution to this problem. A 3-pot TDI coupled to a long-ratio 'box creates a compromise scenario. A map can only work with the hardware it instructs. If a map could be written that was more suited to the JDD 'box, I fail to see why it wouldn't also be suited to shorter-ratio gearboxes. Who wouldn't want more power across a greater rev range? Creating maximum output across the entire rev range is what remapping aims to achieve.
Kaz, is it possible that your turbo is tired? Are the turbo's bearings worn such that it doesn't spool with the same ease that it might once have done, and that it therefore stalls quickly?
Cheers,
Tom