I went to the www.nastyz28.com website to figure out how to identify the engine block numbers. The number on my engine is V0624TDS under that is C8B171348 on the other side of the engine it has 41 GM 3970010. I was told this was a small block 400 ... but when I searched the numbers on that website the suffix code TDS was not listed. Does anyone have a website address they know of that would have a more complete list? Or does anyone know by these numbers what type engine this is. Thanks for any help. - mel