A while back I said that I would post my solution for the cons of heater removal discussed in this thread:
http://forums.hybridz.org/showthread.php?t=113468
Anyway, love it, hate it, here it is!
Let me start by saying this is not a full on heater replacement but more of an electric defroster and light duty heater. I do not think it would put out enough heat for you snow state guys. My primary concern was a defrosting function, being that I am in California and don’t need a whole lot of heat anyway.
I started with 2 ceramic 12v heaters purchased from ebay (Like these-link). Which by the way, the internal fans are complete garbage. Then I cut up the heaters a bit, took out the fans, soldered in the wires (I didn’t like the connectors).
After that I took the stock defroster ducts and cut the bottoms off. A little plastic cement here and there, some silicone to seal it all up and wallah.
For air flow, I took the front off the stock heater box and filled the center tube with epoxy (needs a bit of bondo to be smooth). Then made an aluminum bracket that mounts to 2 of the original holes for the factory heater box. I believe the original heat ducts will reach the defroster vents just fine, if not I am just going to use some flex tubing form McMaster Carr. For a fan I am using a high out put 12v computer fan. The fan puts out plenty of volume but I am not sure it has the hp to deal with the back pressure. If it falls short I am going to use a squirrel cage blower, like this one (link), which should do the trick. The larger blower will tack on about a pound or 2.
On the bench the whole system seems to work great, decent amount of air, and good temperature at the vent. It is also very light weight.
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