Part of the turbo lag is the size, a pair of smaller turbos is usually a way better solution. The bike isn't pulling that much air at low rpmsto get the turbo go. I test drove an early Volvo 242 Turbo my senior year I was considering buying. I didn't rev it enough to get it going pulling away as traffic at the light changed... I was driving a Datsun B210 4 door that was very light and very light construction and it was very peppy. So, never having driven a low compression turbo motor before I was more than shocked by the lack of bottom end. I pushed the go pedal down and it was at the bottom of a hilly area in a college town with 6 lanes in this city in NE TN where I attended college. The turbo spooled up and zoom we were up the hill in 1st gear below redline but it scared the salesman and surprised me.
The early 240 non-intercooled turbos we're very laggy and the later ones with intercoolers we're higher output and turbos on cars was a new adventure. The water cooled turbos we're far longer lived and more refined
The oil cooled turbos coked up if you overheated them and didn't do frequent oil changes.
Now twin turbos or single turbos on autos are becoming commonplace.
Who made the first practical twin turbo automobile?