22 inch tophat too big?

[haaks]

Hi everybody

I've been reading for a few days now, preparing myself for the build! I think I have most aspects covered (thanks Phil, Retired2 and many other very active posters!!), but there is one thing I found conflicting info about: the diameter of the chamber. This is my setup:

2HP DC with a 12 inch blowerwheel, 6 inch blowerhouse inlet, 5" outlet, enlarged to 6", vents outside.

I'd go with the measurements on the blowerhousing and choose 6" outlet and tangential round to rectangle inlet on the separator. That's pretty big. I notice most people with my setup go for a 20" diameter chamber, but size isn't a constraint for me, so I could go for 22" too. Some people seem to run into trouble with this size separator, although there could be many other parameters responsible for bad results. The only semi scientific statement I found about this whas quoted from Bill Pentz website, it came down to this: it takes a lot of energy to compress and spin air around in a cyclone, so the weaker your blower the larger a cyclone diameter should be, and it whas concluded in the thread on this forum that this probably goes for Thien baffles too.

Any comments or advice?
Thanks!