Just came across this product and would allow a spacer plate to sit on top of any A series by adding this paste and heating the block to the right temperature using an Open or block ontop of an electric stove and gas torch on top of the spacer plate.

Then Sleeve the A series and you have a tall block for stroker A15 offset ground crank using longer cheap Honda or Mitsubishi H beams.

http://www.youtube.com/watch?v=gRNi17RmGBo

https://www.youtube.com/watch?v=HOVrH6HdQP4

85,000psi strength and melts at 580 degrees celcius
http://www.muggyweld.com/?view=ssq6

I think the block would likely warp heating it that much. You'd be better off with a two part epoxy like one of the Masterbond products. http://www.masterbond.com To maintain a good seal you'd want the spacer to be grey cast iron like the block and to either keep the epoxy as thin as possible or have a similar coefficent of thermal expansion.

I thought so too but heating cast iron blocks correctly pre & post welding seems to be successful enough for many to have it done over the years not just for vintage block repairs. In this case the block has no welding just careful 580 degrees for the solder to melt and bond both surfaces perfectly, I agree cast iron spacer is the best choice.

I'd much rather run short pistons with only one compression ring to allow for a longer rod. It's a reliable and time tested option.

Muggyweld do some good welding rods and alloys, but I still wouldn't try increasing deck height on a cast iron block this way. It's a hard enough proposition to do it on an alloy one.

On further thoughts the block only needs to be heated to 200-250 degrees celcius and oxy on the head plate at 570 degrees for a short time then slow cooling bringing down the hot plate temp down for the block every hour 50 degrees after that cover in sand box for slow cooling over a few days. Should that be safe?
Block is getting the most heat at the top.