Thread: Guess on engine based on intake manifold casting number?

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If that's the intake casting number, it's a 1973 - 77 two-barrel intake for a 305 or 350. Do you know the difference between big-block and small block Chevys by how the valve covers and/or exhaust manifolds look?

I can't tell based on the way the manifolds/covers look but it is very obvious that it's a BB. That' the whole reason why I posted here as I was confused. I've had a friend who is a diesel technition and the person that drove it till gas prices made it unbearable to drive tell me that it was a big block, and I have personally looked at it side by side with a smallblock. Believe me, It's big. It is more likely that i got the numbers mixed up as the best method I could find to get the numbers from the back end of the manifold was to make a crayon rubbing of it. The sixes could possible be eights, I am not sure.