wiring a boost cut relay
Thread Starter
Joined: Nov 2013
Posts: 6,389
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From: Portlandia
wiring a boost cut relay so I bought this eboost 2
one ground output I will use to trigger a relay to turn on my meth pump
the other ground output I want to use as an overboost cut via the IAT
basically I want to use a ground signal to ground another signal
I'm having a brain spasm trying to think of how to do it without two relays
one ground output I will use to trigger a relay to turn on my meth pump
the other ground output I want to use as an overboost cut via the IAT
basically I want to use a ground signal to ground another signal
I'm having a brain spasm trying to think of how to do it without two relays
So if you wanna use eboost ground to control a relay to ground an signal you would put the eboost on pin 85. 12 volt switched to pin 86. Chassis ground to pin 30 and the signal you wanna ground to pin 87. Eboost sends ground to relay. 12 volts and eboost signal actuate coil in relay and pin 30 (chassis ground) will be connected to pin 87 (signal). If I undersood you purpose correctly that will do it no problem.
Thread Starter
Joined: Nov 2013
Posts: 6,389
Likes: 558
From: Portlandia
so I misunderstood what I needed to do to make this work and wanted to clarify if anyone came across this thread down the line.
to use the eboost 2 aux output to cut the IAT signal and act as a boost cut (pulls timing due to pcm "seeing" -38*F) you must wire the relay in a "normally closed" configuration and use the ground signal from the eboost to trigger it.
you must use a resistor type relay as closing the coil with voltage across it will generate a feedback spike that can damage the eboost.
so the relay wiring will be as follows
86 12v + switched
85 eboost signal (ground)
30 IAT sensor "in"
87a IAT sensor "out"
I hope this helps and if I've made a mistake please ream my *** publicly
to use the eboost 2 aux output to cut the IAT signal and act as a boost cut (pulls timing due to pcm "seeing" -38*F) you must wire the relay in a "normally closed" configuration and use the ground signal from the eboost to trigger it.
you must use a resistor type relay as closing the coil with voltage across it will generate a feedback spike that can damage the eboost.
so the relay wiring will be as follows
86 12v + switched
85 eboost signal (ground)
30 IAT sensor "in"
87a IAT sensor "out"
I hope this helps and if I've made a mistake please ream my *** publicly
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Joined: Mar 2014
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From: Ohio
I think the Eboost2 is a little over-rated.
Get an adjustable voltage triggered relay and wire it to your MAP sensor signal. You might have to do the math to figure out what kPa is equal to what voltage for the cut, but you can just pass the IAT signal through the relay and when it gets above X voltage it will trigger and switch circuits disabling the IAT. Its like $25 for everything.
Can be used for Overboost (MAP signal), Overtemp (ECT signal), etc on a stock PCM.
Can also be used to turn on Meth injection or a 2nd fuel pump if you set the voltage just right.
Get an adjustable voltage triggered relay and wire it to your MAP sensor signal. You might have to do the math to figure out what kPa is equal to what voltage for the cut, but you can just pass the IAT signal through the relay and when it gets above X voltage it will trigger and switch circuits disabling the IAT. Its like $25 for everything.
Can be used for Overboost (MAP signal), Overtemp (ECT signal), etc on a stock PCM.
Can also be used to turn on Meth injection or a 2nd fuel pump if you set the voltage just right.
Thread Starter
Joined: Nov 2013
Posts: 6,389
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From: Portlandia
yeah pretty much. I thought it had two outputs...nope just one. So I'll end up spraying water/meth with a hobbs switch.
I got it to play with boost by gear/rpm. It was a cheap "scratch n dent" sale item.
but at retail it's very expensive little toy that is and kinda hard to set up.
currently I rate it a 5/10 would not purchase at retail
I got it to play with boost by gear/rpm. It was a cheap "scratch n dent" sale item.
but at retail it's very expensive little toy that is and kinda hard to set up.
currently I rate it a 5/10 would not purchase at retail
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Restricted User
Joined: Mar 2014
Posts: 7,192
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From: Ohio
I have my $5 overboost protection tied into my PCM. It just kills power all together and turns it back on as soon as kPa drops (less than .25 seconds). I had it killing the 12v to the coils but it would make a spectacular backfire when the plugs start lighting all of that unburned fuel.
You can do 90% of the things that the Eboost 2 can for about $30 and some clever thinking. Even boost by gear is laughably easy.
You can do 90% of the things that the Eboost 2 can for about $30 and some clever thinking. Even boost by gear is laughably easy.
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Verdad Gallardo Thread Starter
Joined: Nov 2013
Posts: 6,389
Likes: 558
From: Portlandia
hoping joe will see this and respond. or anyone who cares to share their opinion
so with one output I can use the eboost to control either an overboost IAT cut
or use it to kick on a water/meth pump
initially I was gonna use it to cut the IAT, but after playing with it for a little bit I realized it already had overboost protection (via the boost solenoid) and maybe I should use the aux output to spray meth.
the aux output has a window (boost psi on and off, rpm on and off) that it's triggered in...so that makes it pretty attractive to use for spraying meth
I have an adjustable hobbs switch on the way I was gonna use to trigger the meth pump. I can use that to do my overboost IAT cut
what y'all think?
so with one output I can use the eboost to control either an overboost IAT cut
or use it to kick on a water/meth pump
initially I was gonna use it to cut the IAT, but after playing with it for a little bit I realized it already had overboost protection (via the boost solenoid) and maybe I should use the aux output to spray meth.
the aux output has a window (boost psi on and off, rpm on and off) that it's triggered in...so that makes it pretty attractive to use for spraying meth
I have an adjustable hobbs switch on the way I was gonna use to trigger the meth pump. I can use that to do my overboost IAT cut
what y'all think?