[Michael C Henry]

I'm installing a Vintage Air heater defroster unit.Everything is vacum controled.I'v eliminated the vacum water valve ( either on or off) With a push pull cable switch combination. The heater door is normaly closed directing everything to defrosters. To Keep the vacum motor on the door from pulsating and wear out early. I figure I'll need a vacum resivoir to keep a steady pull and not pulsate.Vintage shows a 5"ball resivoir.They don't offer a check valve.Summit offers a resvoir but doesn't give dementions.Anybody done the shopping and know of a perfect resivoir for under dash?