Hi Guest!
Hey - did you know if you click on the title of a thread it will take you to the first unread post since you last visited that thread?
but were afraid to ask: 
STOP!! Never post your email address in open forums. Bots can "harvest" your email! If you must share your email use a Private Message or use the 
smilie in place of the real @
Pretty Please - add it to our Events forum(s) and add to the calendar! >> 
Depending on the cost of a replacement block, stitching is an excellent solution. It's mature technology and used extensively to repair marine engines that cannot be (easily) removed from ships, so if you'd like to re-use your block, I'd make enquiries as previously suggested and see how much it would cost.
There are two ways to weld: Firstly by taking the block to a cast iron welding specialist who will, as Michel says, heat the whole thing in an enormous oven to a dull cherry red and then gas weld the cracks, but it take days and costs a fortune. Alternatively frost damage cracks can sometimes be arc welded successfully with nickel rods, I've had repairs done to TR heads where the thermostat mounts and to the block where the recess for the head studs has cracked. It's not expensive and if the cast iron is good quality, it's fine. But is can trash the block if you're unlucky. Some braze cracks, but I've only seen unsuccessful attempts, one to a BMW 328/80 engine where over tightening head had lifted and cracked the block surface.
I should add that the full process of gas welding a heated block usually causes some distortion and all surfaces need checking to make sure they're still true. The camshaft and main bearing housings may also require line boring.
There are two ways to weld: Firstly by taking the block to a cast iron welding specialist who will, as Michel says, heat the whole thing in an enormous oven to a dull cherry red and then gas weld the cracks, but it take days and costs a fortune. Alternatively frost damage cracks can sometimes be arc welded successfully with nickel rods, I've had repairs done to TR heads where the thermostat mounts and to the block where the recess for the head studs has cracked. It's not expensive and if the cast iron is good quality, it's fine. But is can trash the block if you're unlucky. Some braze cracks, but I've only seen unsuccessful attempts, one to a BMW 328/80 engine where over tightening head had lifted and cracked the block surface.
I should add that the full process of gas welding a heated block usually causes some distortion and all surfaces need checking to make sure they're still true. The camshaft and main bearing housings may also require line boring.
