If I was going to use a turbo it would be in conjuntion with the SC. Some of this seems silly though as I am just as guilty as anyone in the quest for HP. I had two 928's. A 79 4.5L with Euro cams and headers. It made 225rwhp and a Euro 85 928 with a 4.7L twinscrew SC with 375rwhp. The 79 I had for years and I could beat on it like no other car I have ever owned. The harder I drove her the more she liked it. Well balanced just a awesome driver. The Euro became available and all I saw was that twinscrew and all that power. It was a pain in the butt on the street, hard to track, had to watch your throttle, the back end would get loose on first to second shifts with less than 1/2 throttle. It was harder to control and much less enjoyable to drive, but she looked good.
If all you want to do is go in a straight line and hit the gas then all that power is needed to have the ET"s for 1/4 mile racing. For a street car, a big block with turbo's OMG where could you use it on the street. 500rwhp good luck with that setup. Give me a 300rwhp SC and try to keep up with me on the street where there are curves, hills, breaking etc. Ricardo said it well in a tread about a well balanced SC with 300rwhp. I agree with him a 100% Well balanced in my mind also means ease of maintenance and not having to worry about stuff breaking. I just wanna hammer it and hammer it all day long, day in and day out!
I love cars and I love power but I want to be able to use it. I wish I had the money to setup a 1/4mile car but I don't. So that means I have to put things into perspective.
A turbo on a SC in conjuntion with the blower would be a mean machine. It would also sound like no other. That will be my quest. Just give me 7 to 8lbs of boost for the top end with a stock ported late model blower and let the power fall where it may.