Aluminum top fuel blocks from Alan Johnson Performance Engineering, Brad Anderson Enterprises, and the like are all machined with “windows” that are thinner areas of the block that are located where damage will typically occur should a connecting rod break. They are machined this way so that the area that breaks can be repaired by cutting out the broken window area and placing a new piece in and welding it up. These replacement window pieces can be bought from the engine block manufacturers, or made from aluminum plate, like the previous repair on the block in this video. It really is as simple as cutting out the broken piece, fitting the new one, and welding it in. But if not done correctly, this simple process can go horribly wrong.

In this video you’ll see Rob Wendland, famed NHRA Crew Chief, takes a top fuel block that had previously been repaired and fix it the right way. Maybe a bit more that the right way actually, as he goes to some extremes to machine the finished product so it is prettier than the norm, but we approve. He walks through the entire repair and shows just how it was done wrong, what he did to correct that, and what he did to make the repair significantly better. Keep in mind, he’s got a cnc machine and such so he can do some of this fancier finish work, but you could make this repair with less machining but the same attention to structural detail and end up with a really strong finished piece.

This is fun to watch. Check it out.