How to tell if you have a 400 Chevy block?

Answer by  carguy22 (73)

There are casting numbers near the rear of the engine where the bellhousing is attached. A 400 small block 4 bolt main will also have six freeze plugs, three per side as opposed to two per side on the 350. 400 2 bolt mains will still have only two freeze plugs.

Answer by  Amber40 (24961)

Well typically the best way to tell is to locate your blocks casting number. Then go online and locate a list of all the block casting number available and locate yours in the list. It should give you detail as to what displacement it is and possibly what type of car it was originally installed in.

Answer by  twiggy (58)

If your car was made between 1955-1998. It is a very common chevy v8 engine. Look on a chevy website, and search the model of your car to find the answer.