I ran a small block 351W stroked to 418 for years and had no problems keeping up with my friends who had 429s and one had a 512 C.I. in his. Now mind you this was on a road course. On a straight long stretch, the big block would pull away from me but not as fast as they had expected. The new big blocks aren't much heavier than the old cast iron small blocks and can be made to handle very well.
As for stroking the small block to 427, the engine builders that I have talked to prefer to keep theirs between 408 and 420. I know of two that have the stroker 427s and they run great and have had no problems with them. As for power, my 418 put out around 530 horse and about 520 pounds torque.
As for fast, they are very fast but you won't have that deep throated rumble that a big block gives. Just remember this is a light car and the more power and torque, the more you have to learn to drive it as it won't be like any other car you have ever driven. If you have a road course near you, I would recommend taking a high performance driving school.
Ron
