hobbs switch placement
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From: Anchorage, ALASKA
Where is everyone placing their hobbs switch? Are you putting it in the charge pipe near the turbo before IC or after?
Also, from what I understand the Hobbs acts as a relay. So I can run the power wire from my battery to the hobbs switch, then to the fuel pump and ground the fuel pump like normal right?
Also, from what I understand the Hobbs acts as a relay. So I can run the power wire from my battery to the hobbs switch, then to the fuel pump and ground the fuel pump like normal right?
most Hobbs switch's are just that-switches, not made to handle high current, but could be used to control a relay-i use them after the i/c'er, in my carb hat
(i run a blowthru) i use mine to trigger the retard
(i run a blowthru) i use mine to trigger the retard
Put the Hobbs switch anywhere it can get the boost signal it needs to suit your purpose. Use a good relay. Run ground to one side of the switch and then to relay pin# 85. If running a fuel pump, I recommend adding a fuse link to the back of the alternator for the absolute best voltage source. Run that voltage source to pin 87 on the relay and also a small jumper wire connecting 87 to 86 to energize the coil of the relay. The relay output will be on Pin 30. Run that to your pump hot wire. When you get in enough boost to trigger the Hobbs switch, it will switch a ground to the relay, and close the contacts, turning on your pump.
i placed mine where there would usually be a 1/8npt port at the end of the compressor housing(where you would normally get ref. for you WG) and put some thread sealant on it and screwed it in.
Same location for me. I like to use them to ground to activate the relays, (no +12v wires near the hot pipes)










