Join Date: Dec 2001
Location: Rozenburg, The Netherlands, Europe
Since you ask if the 400 crank is a direct replacement the answer is no. The main bearing journals are larger and have to be ground down to the size of your 350 block. If you buy a 383 stroker set this modification is already performed to the crank supplied in this set.
In my opinion it is best to rebuild the 350 engine you have now with some high performance parts, especially if it is the first engine you build. Another factor overlooked by many here is that parts in Sweden, and in entire Europe, are much more expensive than in the States. I think you can get close to 375 - 400 hp within reasonable cost with the 350 engine.
Further more it is important what kind of car you have, how is the cooling system, the fuel system, the transmission, rearend and even brakes. Because if you build a really strong engine some of these systems may not be strong or adequate enough. So tell us a little more about the car, and the engine you have now.