Engine size


#1

Did general motors ever make a big block 350


#2

There was a 348 big block. If I recall correctly they were mostly in trucks.

Pontiac had a 350 that might be considered a big block, but I think they pretty much used the same block for all of their engines.


#3

Pontiac had a 350 that might be considered a big block, but I think they pretty much used the same block for all of their engines.

The Pontiac 350 was NOTICEABLY bigger then the Chevrolet 350. Although Pontiac started using the Chevy 350 since the early to mid 70’s. The Pontiac 350 was the same outside dimensions as other GM big-blocks like the 396 or 427.


#4

It is in a GMC 2500 vandura cargo conversion van and is marked 5.0 but is much larger than most of the 5.0’s I have seen.I was told it was a big block 350,thats why I was wondering.


#5

Thanks Mike, my recollection of Pontiac motors is quite hazy at best.


#6

Chevy made a “big block” 400 I think, same basic block as the 427-454. Used mostly in trucks. They also made a small block 400. 5.0L is a 305 cu.in. and 5.7L is a 350 cu.in.


#7

What do the valve covers look like? Long and narrow means 305, 350, 307, etc. Low and wide means 396, 427, 454, or possibly that obscure 402 that was used for s short time. (402 was a bored 396)

My engine guide says the 400 (narrow valve covers) is a small block that is simply bored to the max.
As to the 305 markings, and if that’s on the air cleaner, then parts interchangeability could be responsible for that.