Unless there is a serious restriction through the radiator I can't imagine there would be anything greater then 1 psi over system pressure caused by pump output. As for the reverse flow, ie, bottom to top,,, It's called counter flow, and yes it can work. My set up has worked flawlessly for 500 hours and I use the Moroso swirl / pressure tank and a air bleed line from the output of the radiator... About 3 minutes into this video shows my set up.....
http://www.youtube.com/watch?v=rCNnEgRkdXc&context=C3e091d3ADOEgsToPDskKmHo69I6bUDuoBHd5YSUfuBen Haaswww.haaspowerair.com
To: flyrotary@lancaironline.net
Date: Mon, 22 Oct 2012 12:40:11 -0500
From: ceengland7@gmail.com
Subject: [FlyRotary] flow path in conventional radiator
I've been doing research on radiators, & my 1st 'experiment' will be a conventionally configured radiator (downflow design) with inlet & pressure cap on top. In reading about issues with conventional radiators, a common complaint is pressure venting due to the water pump + system pressure exceeding the cap's rating. Crossflow types like the Sirocco are supposed to avoid this because the cap is at the mid-point in the flow through the rad, which drops some of the pressure seen by the cap.
Here's my question: Is there any reason a conventional rad can't be fed from the bottom, instead of the top? This would achieve similar effect as the crossflow cap location (all the way to the end of the flow path) & any air could be vented using the existing fittings. I'm also considering the removal of the spring loaded seal, & moving the pressure cap function to a separate swirl can. By doing this, the existing over-pressure port could function as the air removal port in the top tank of the radiator.
What am I missing?
Thanks,
Charlie