Wow! That's alot of questions to digest all at once. The 350 that was quicker than yours could have had different fuel mixture than yours or timing. I would get the timing chain and injection pump timing checked. If either are off you should ask if the latest cam sprocket and tensioner are installed. If not update to them and a new chain then have the injection pump timing checked again. If all of this is on the money and you are getting full boost from the turbo, the car should perform well!
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