Not Chevy or GMC,
But Hall-Scott made some really big ones.
I've got a manual here in front of me for a "Hudson Invader 168" marine engine, which was a Hall-Scott design made by Hudson during the war.
The same basic Hall-Scott engine was also a truck engine.
The marine version is 997.8 cubic inches and 250 hp at 2100 rpm.

The truck engine eventually evolved into a 1,090.6 cubic inch with a larger bore of 5.75" and the same stroke of 7".
This engine was in the Pacific M26 "Dragon Wagon" among other things.

A great article in the January/February 2005 wheels of Time about Hall-Scott.

Or do you intend to limit this discussion to only GM engines?

Grigg


1951 GMC 250 in the Project Journals
1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
1952 Chevrolet 3800 pickup
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"First, get a clear notion of what you desire to accomplish, and then in all probability you will succeed in doing it..." -Henry Maudslay-