As title really.

My pretty standard YB on a L6 and Stg1 chip, while boosting at low rpm like you'd expect on the 4x4 Saff T3 and manifold it's on, feels SO dead and unresponsive it's daft really. And feels heavy and unwilling to rev, despite actually being fast (I wouldn't say it's actually down on power for the spec).

My other car, another 2ltr turbo, albeit much shorter stroke, has a turbo literally twice the size (good for ~550-600bhp and isn't on full boost for at least 1000rpm more than the Cossie one) but has a night and day difference in throttle response even off boost, and also how freely it revs. 7k in that feels less harsh than 4k from the YB. It's far nicer to drive, despite the much bigger turbo with the higher boost threshold.

SO, is there any way I can help the YB rev more freely, and more importantly have better throttle response? As if so, I'm keen to do it!

Before people start replying, please note, when I'm talking about response, I don't mean boost threshold (ie when the turbo boosts), as it boosts at low rpm anyhow, I really do mean throttle response (even off boost), and how quickly the turbo responds to putting my foot down (lag), whatever.

The 'Revvynes' issue, for want of a better word. Well, a lightweight flywheel is the only thing I can think of, as a Cossie flywheel is pretty fooking heavy, right? Gearing-wise it's geared to just over 170 (real speed) at 7500rpm, so I don't want it any shorter, and that's about the same, if not shorter, than my other car.

My first thoughts for the shitty response is the L6 and random ancient Stg1 Chip.
If I remember rightly on my old Cossie, changing from L6 to L8 seemed to wake the car up hugely, much more responsive, probably due to having a TPS that picked up more throttle positions than the L6 one does.

Aside from the above though, and things like ALS of course, any ideas?

Cheers!