Any opinions on using this stuff to check the engine for cracks?

 

Works fine - I keep a Magnaflux-made dye check kit around for checking castings.

It's more of a spot-check setup; it's not something you'd use on the whole part, it's more to check a suspect area. But, it works well.

Expect to find small kits at a well-stocked parts house, you can find larger cans at MRO houses or welding supply shops.

 

Thank you, considering a 4.2 stroker now so I may just have the shop check the block anyways.