1969 Camaro Smog System Question

[Unreal]

Rick,
I know that's why they used the over valve cover one on A/C cars. My point was that if they used the A/C type one on a solid lifter car, they would need to remove the check valve every time they adjusted the valves. It doesn't make sense that GM would use the over cover unit when they had an alternative already in the parts bin that would not require disassembly to adjust the valves.

[Mr70]

It was probably all about cost & simplicity to themselves.
Why make two design tubes,when one design would accommodate both,where as the earlier would not.As at that time,they were well in the planning/design stages of the 71-72 models,most likely seeing the writing on the wall with the mandatory implement of A.I.R being required on ALL vehicles in the upcoming years,which meant A/C equipped Hydra lifter BB too.
Add to that,I think they pretty much new 99.9% of all new car Hi-perf owners were going to pitch the entire A.I.R. system within one hour of taking delivery anyway,so it getting in the way of adjusting valves would become a moot point.

[nuch_ss396]

[ QUOTE ]
....Add to that,I think they pretty much new 99.9% of all new car Hi-perf owners were going to pitch the entire A.I.R. system within one hour of taking delivery anyway,so it getting in the way of adjusting valves would become a moot point.

[/ QUOTE ]

Rick,

That is exactly what I believe the rationale was for use
of only the over the valve cover tube design. Does anyone
remember seeing a SHP engine with the AIR system intact
back in the day? I sure don't.....

Taking off the SMOG system didn't cost anything. You
gained some HP! Weren't we all trying to squeak as much HP
out of these cars as we could?

And as you've observed, GM knew most SHP owners were removing
these systems to gain HP. So it was a

Steve