Just my opinion as a long time 944 owner with a LS1 swapped 944 Turbo and an air cooled 911.
The chassis of the 944 is really what makes it special. The forgiving and predictable handling are the 'experience' There are plenty of engine choices from the 8v 2.5L n/a, 16v 2.5L n/a, 8v 2.5L turbo and 16v 3.0L turbo. All of the engines are good and offer different powerbands; however all of them are forgettable in the overall experience of driving the car. The powerband of the LSx engine in the 944 is incredible because the chassis handles it so well, the LSx swapped 944 comes close to the experience of the early 911 where you have a complete package; chassis and engine that makes for something very special to drive.
The 911 on the other hand; the engine is totally part of the driving experience and i think you loose part of the character of the 911 without it. While i could care less what the purist think of my 944, personally i wouldnt do it on an earlier 911. A 996 is a different story! I think you will definately alter the value of a 911 with an LS swap and i couldnt say it would be for the better. The 944 on the other hand will never reach the pricing segment of a 911 so i dont think there is much to loose on the value of one compared to a air cooled 911.
5.7L LS1 in my '88 944T. 380whp/360ft-lbs. It hauls ass
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