Quick question about Hobbs overboost switch

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poshatch
Posts: 853
Joined: Thu Oct 15, 2009 7:44 am
Car: p.o.s. 1990 240sx hatch

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Hey all,

I have a Hobbs overboost switch that i installed today and i want to verify that i installed it correctly.

I read online that you splice it into the black with the red stripe power wire going to the ignitor coil.

engine is a 91 ka24de

so it sits like this without overboost

Power from ecu -> in switch COM -> out of switch on top pin -> ignitor coil

and then when it does have overboost

Power from ecu -> in switch COM -> out of switch in middle (the one that is selected when the switch clicks on according to the side of the switch) -> grounded to chassis.

Will this set up work or is there any ill effects of having the power wire be grounded?

Thanks everybody!


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poshatch
Posts: 853
Joined: Thu Oct 15, 2009 7:44 am
Car: p.o.s. 1990 240sx hatch

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bump!

i know this is a common thing i just want verification that im not going to do any damage grounding that power wire

cause i could just leave it open and taped and it will just "unplug" the wire instead of grounding it

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poshatch
Posts: 853
Joined: Thu Oct 15, 2009 7:44 am
Car: p.o.s. 1990 240sx hatch

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bump!

seriously? nobody has any info on here about this?

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Razi
Posts: 28681
Joined: Sun Dec 31, 2006 9:52 am
Car: Moo

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We have a write-up on it, but I haven't read through it in a few years.

http://www.nicoclub.com/archives/how-to ... again.html

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neverlift
Posts: 3700
Joined: Mon Apr 24, 2006 6:26 am

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to test function you simply jump the terminals on the hobbs..

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poshatch
Posts: 853
Joined: Thu Oct 15, 2009 7:44 am
Car: p.o.s. 1990 240sx hatch

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well im going to get access to a compressor and adjust the switch to 11 psi since i plan on running 8psi and ill allow a few psi for some breathing room so thats i how i can test and set it

but i was going to try to wire it to serve as an "unplug" function, i just dont know if grounding it or just simply covvering it and letting it switch to a terminal connected to nothing would be the best course of action.

I have read that writeup but it refer's to ecu pins and i looked them up online and they didnt seem to match anything relevant

i dont want to test the setup and have something bad happen you see lol

i guess ill just try it ungrounded and if it works it works


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