[patrickt]

It can't hurt to price out a 428, but it will cost you more than a 390. In my ERA I have a 428 service block that was cast in 1974. It is bored and stroked to 447CID, mild solid lifter cam, and is 100% streetable. From the outside it looks just like a 390; actually it looks just like a 427 sideoiler because you can't wiggle underneath to see the the galley or bolts. Sideoilers are nicer than 428s; 428s are nicer than 390s, but they all look the same and, if you're not careful, you can go broke building your Cobra. You have to watch your own costs as no one on this forum will watch them for you. Just take a look at the Cobra Country site for all the Cobras that are for sale with less than a couple of thousand miles. Many of them are "overbuilt" for street enjoyment (500+ horsepower, very rough below 3000RPM), and the costs got away from the owners. Remember that toy you're building is going to sit in the garage a large portion of the time and, while it's doing that, it doesn't throw off any interest. Unless you can really afford to ignore it, keep a sharp eye on what you're spending.