How do you tell if a 350 SBC has been stroked or not?

[testdepth]

The engine in this hot rod drag truck was installed before the last owner bought it. He ran the number off the back of the block and it shows as a 68 Camaro 350 block. It has a mild cam in it. How do you tell if the motor has been stroked to 383 or 355 or something else? It could just be a 350 with a mild cm but I doubt it.

Any exterior physical differences?

Does it have to be torn apart to figure out what I am dealing with?

 

[Kahrnut]

Measure the length of the stroke through the spark plug hole, by rotating the engine by hand(take out all the spark plugs, so it turns easier).

 

[Jranger]

Stroke is in the crank shaft... 383 is a 400 crank in 350 block.

 

[davans]

350 crank has a 3-1/2” stroke.
400 is 3-3/4”

 

[BillsCamino]

Generally, the bottom edge of the cylinder bores have to be relieved for the crank throws on a stroked Chevy 350 block.
Pull the pan and look...

 

[Bennyboy]

Karhnut is right, just measure the difference between top dead center and bottom dead center. 3.48” is standard, 3.75” is a stroker.

355 will still have a 3.48” stroke. Just a 0.030” overbore.