Difference Between Conshelf 20-series And Se-series

[guruboy]

Were there any performance differences between the Conshelf 20-series (20,21,22) and SE-series (SE,SE2,SE3) 1st stages?

I understand models of each line were being sold at the same time and that they have differences in terms of the number and size of ports on the 1st stage. Not finding much information on performance besides one post where someone claimed the SE-series had more air flow though.

As far as the second stages go, is it true that the 20-series had plastic bodies while the SE-series had metal in plastic?

 

[guruboy]

Found an SE2 and the second stage looks like just a plastic body.

 

[USdiver1]

I believe that the main first stage difference was that the SE series used oversize (1/2") LP ports, while the 20 series used standard 3/8" LP ports.

2nd stages were all plastic in both series SE and 20s

 

[Luis H]

Many manufacturers tried the 1/2” port for a while as a higher flow and higher performance sales gimmick. They have all gone back to the 3/8” ports. It was a nice sales gimmick, but in the real world it doesn’t make a difference.

The mechanism in all the Conshelf first stages is the same.

 

[Fishpie]

First stages.
20....same as the 14 but in satin chrome 3 3/8" LP, 1 3/8" HP
21 and 22.....4 3/8" LP, 1 7/16" HP
SE... 3 1/2" LP, 1 7/16" HP
SE2, SE3 and Select...1 1/2" LP, 3 3/8" LP, 1 7?16" HP
....some (may be all) 22's and SE3's have a removable volcano orifice.

Second stages.
All use plastic bodies.
Select has soft purge cover.
SE3 and 22 use new style plastic

......as a totally unrelated edit, I spent a night earlier this week parked next to the M/V Venus at Espiritu Santo near La Paz. I'm not a big fan of stink pots but Steve Jobs missed out on this fabulous display, she's quite an awesome creature (it must be impressive as this is the first time I've ever used awesome as an adjective ....... here's another first for this week, I also was heard saying " I think I would like a yogurt for breakfast".....strange times indeed.