is to allow time for the turbos to spin down before the oil pressure goes away. Figure it like this: After a spirited run you pull in to your favorite burger bistro and turn the key to off. The turbos have been spinning at a very high speed and will coast for a few minutes. The turbo timer allows the engine oil pump to maintain lubrication till the turbos slow down to a reasonable speed before the oil pressure goes away. The second function is to allow the turbo to cool sufficiently to reduce coking of the oil trapped in the turbo when the engine stops. so the electric water pump would be a nice addition but would not remove the need for a turbo timer. As I said this is just my understanding. Correct me if I am wrong.
