The photo of the ZL1 engine on a stand is from the February 1995 issue of Chevy High Performance. It's the block from ZL1 #26 completely rebuilt to OE specs to see what it would do on the dyno. I doubt that is an OE air cleaner; we provided some parts for the build and were credited in the feature.
The dyno results are on this site: http://www.camaros.org/copo.shtml
Bill Porterfield owned the #26 engine and ZL1 #3 at the time; there may have been an ulterior motive for building the engine. The owner of #26 had the engine from #3. Despite offering this engine and $$ neither engine has returned to its original chassis.
The other photo is one I posted in the COPO article. The PHR test of #5 was re-visited in the June 1998 Hot Rod by Ro McGonegal. With only headers and wimpy 6.5" slicks it went 11.64. That's Hellcat territory, 46 years ago. Imagine what that car would do on today's tires.