Blast from the past #2, 1974

[Nemrod]

Thanks Dustin, I was thinking a bit earlier but couldn’t recall.

The 156 BA CE Approved was late 90s when CE certification became important and the larger valve was needed (I assume) to meet certification. Assuming is always dangerous but regardless the main functional change was the exhaust valve now the same size as the G250 but still with a more restrictive tee and no VIVA.