if you are going to go out and buy all new **** the windor swap wont be cheap. but if you know what you are doing and look around you can do it cheap. if you are comparing a no expense spared dart 8.2 deck build to a cheap overbore only windsor build, you are comparing two different animals. the 8.2 will be faster, but, ive gotten 10:1 358" windsor shortblocks with ported stock heads into the high 10s naturally aspirated with a flat tappet cam. so it can be done. if you are reusing the stock windsor crank, rods and block it can be a cheap build that will hold 700hp. even if you are going to buy a cast 408 rotating assembly its still not that expensive and can take you into the low 10s on motor if done right. they are no 4 bolt block but they will live a lot longer than even an early stock 302 or mexican block.