Meth injection fail safe options

[El_bigote_AJ]

Hi Guys,

I'm going to be install a meth injection kit this weekend and I'm trying to weight out my fail safe options. the kit I'm using is from AEM and their controller does have a signal beyond the dummy light that gets triggered when there is some issues, I initially wanted to use the system by just adding the FSB from Burger since Im jb4, but per George the AEM kit wont work with their FSB and I'm not going to be JB4 for much longer so i will still need a stand alone option.

what have others done as fail safes?

I was thinking of grassroots type concept using a normally closed solenoid with a relay between that and the boost safety signal that would then be connected to a boost tap line (not sure it that's even big enough to let off enough boost pressure quick enough) or welding a 1/2' or 1/4" bung to the charge pipe.
but maybe there is better options that have been done, ideally it would be great to have it built into a tune to throw the car to a safety map but i don't know if our tuning options for our platform have something like that.

I'm all ears
.

 

[The Dude]

how much voltage is required to trigger the BOV? Imagine being able to vent all your boost immediately if the failsafe gets tripped.

 

[cr_sti]

I have done exactly zero research on this, so with a grain of salt but..

Couldn't you use a relay to gnd the wastegate if a fail occurs? I assume gnd=open wastegate. Then you're just naturally aspirated until the fail is fixed. Could be easily bypassed too, if you wanted to load a non-meth injection map.

I'm not familiar enough with the circuit to speak intelligently, or know if that would damage anything (ie - might need to add a resistor to limit current draw etc) Just a thought

 

[local]

Hobbs switch paired with my AEM controller

 

[cr_sti]

Hobbs switch paired with my AEM controller

What does the Hobbs switch switch? It activates the flow of meth?

How does it act as a fail safe if an issue/error occurs?

 

[El_bigote_AJ]

Yes please explain, I though a Hobbs switch issues air pressure to trigger a connection like an closing the loop of a ground.

 

[local]

yes hobbs is boost activated so if boost goes over the hobbs psi then the switch to the AEM controller is on

I was only using the wmi for cooling. so it wasnt as dire for me as it would be for someone running a tune that was expecting the wmi to be present at all times. i just had the wmi spraying on top of my basic tune to keep iat's down. Mainly i was concerned with the AEM board failing in the on position or getting an inaccurate reading and spraying non-stop

Perhaps im misunderstanding the post and you guys are looking for something more than this?

 

[El_bigote_AJ]

Ok thanks for clarifying, yes what I'm looking for is ideas that's revers of what you did. Your set up was not a fail safe it was just a secondary means of telling the controller to turn on in place of the controller, what i doing is building a failsafe that will cut boost if the WMI stops working or has an error as a means to protect the engine.