225 /6 at 250HP?

I agree with badvert65. V8's will likely always be more cost effective to build for hot rodding. 250 Hp at flywheel is not impossible with a 225. But the more you "pump" up any engine, the more likely durability is going to decline. I think of the many 1.8 and 2.0L VW's I've seen running in the 9's in the quarter mile but grenade themselves every 10 passes unless rebuilt every 9 passes. An exaggeration but not by much. I love a hopped up slant but, if just starting out and on a limited budget, the V8 is more cost effective and doesn't have to be pumped up to the degree a six would to get to your stated goals of mid 14's and 0-60 times in the 6-7 sec. range.