wiring in a hobbs switch???

[karolko]

my plan is to use a rpm window switch, tps switch, and a hobbs switch to control my nitrous for launch assist.

msd produces a tps/rpm activation combo box that does the two of them. the box can hold up to 25 amps, so no relay is required, so here is my question....

how are you guys qiring in you hobbs switches? are you letting the full current pass through them, or are you running the switch through a relay and then to the solenoids. if you ue relays, where are you getting a low amperage source from the car to go to the hobbs switch???

please shed some light.


Adrian

 

[Alky V6]

I run a precision switch that can handle the current of both solenoids.

 

[karolko]

what is that? and where can i get one.

also if i jsut rum the hobbs switch for the ground, it will not have any current going through it. is that correct???

 

[Lee Thompson]

Ground

I run the ground through the Hobbs switch. Most GM wiring is done this way.

 

[karolko]

what does any one thing of this type of hobbs switch???

Coolingmist water methanol injection systems

 

[Razor]

Every switch has a current rating, as does every solenoid or xxxx.

If the switch cant handle the current load, then you use a relay that can. And use the switch to command the relay.

Ask the MFG of the device what its current rating is. There you have your answer.

HTH

 

[salvageV6]

The Honeywell Hobbs switch available at NAPA stores is rated at 8A current on it's gold contacts.

Should run a few solenoids for ya.

About $30 at NAPA, slightly less at a Honeywell distributor under part number 76575 for Honeywell.

Adjustable and available in high and low switch pressure activation.

1/8" NPT pressure fitting easily adaptable to hose barb with a common fitting from any parts store.

I also use snubber diodes on add on relays and solenoids in the car to reduce voltage spikes that can affect other electronics.

 

[salvageV6]

The NAPA switch is in the Balkamp catalog there, two or three ranges for the switch, I use the 15-60 psi. version for some alky. solenoid switching.

The Coolingmist switch should also work just fine in the 1-25psi. rated range.

 

[coolingmist]

what does any one thing of this type of hobbs switch???

Coolingmist water methanol injection systems

Our switch has a 10 AMP limit. Its adjustable from 1-25 PSI, you can run upto 100 PSI manifold pressure into the switch.

If you want to integrate MAP, TPS, RPM and more into a window switch, look at this. Its much easier than what your trying to do.

Coolingmist water methanol injection systems

 

[karolko]

Coolingmist, with your product how would you program in a hobbs style switch into that box of yours.

i was planning on running a msd tps/rpm switch along with the hobbs switch for the boost.

 

[coolingmist]

HI, its rather simple. you have 2 options.

option #1 is use your MAP sensor and connect to one of the 0-5V Inputs. Lets say you want it to turn on at 15 PSI, find out what voltage 15 psi IS AND ENTER THAT AS the activation point. it works just as well.

option #2 take our switch or a hobbs switch, give 12V power to the COM port. Take the NO (Normally open) and connect to one of the 0-5V input. Set the switch to turn on at what ever psi. In the software you tell it to activate one of the ouptuts when the input has voltage from the hobbs switch.

This device can do alot of things and has 5 outputs so you can set multiple windows and even do conditions such as integrate TPS, MAP, EGT or any other sensor. It can datalog and program a 0-5V output based on a single input or any 2 inputs in grid. Its the best bang for the buck. It can activate nitrous or alky injection as well.