Water injection control using LED 18

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Minami Kotaro
Experienced MS/Extra'er
Posts: 327
Joined: Sun Sep 12, 2004 4:41 pm
Location: Somewhere in TN

Water injection control using LED 18

Post by Minami Kotaro »

I want to use LED 18 to trigger my water injection, since it's simply on/off.

I have rigged up led 18 to x12. The hot wire on my water pump's relay runs to s2 on the relay board.

Now, I have LED 18 set up as Output 4, source MAP, 140 as the activation point.

It doesn't work. The pump works if I touch the relay wire to the positive terminal on my battery.

Is there something else that I need to set in MegaTune or should I suspect my LED 18 mod? The LED 18 is on all the time when the key is on or car running.
1967 VW Beetle
2276 cc
v3.57 board, MSNS-e 029v, EDIS
Check out my ongoing story.
jsmcortina
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Post by jsmcortina »

How have you wired your relay? The transistor supplies a ground so one end of the relay should always go to +12v and the other to X12. Don't forget the protection diode across the relay terminals.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
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Minami Kotaro
Experienced MS/Extra'er
Posts: 327
Joined: Sun Sep 12, 2004 4:41 pm
Location: Somewhere in TN

Post by Minami Kotaro »

http://static.summitracing.com/global/i ... -20001.pdf

Look at Electrical Diagram Stage 1.

It's wired like that, except the red wire to the kit's pressure switch is the wire I plugged into s2 on the relay board.

Red wire - s2
Black wire - ground
Yellow wire - to + terminal on battery, fused
Green wire - to red + wire on pump

I'm not sure if I did the correct LED modification. I did it just like the LED 17 ignition mod (resistor from - leg to right side of, er, that other component, and then a wire to x12). Was this not correct?
1967 VW Beetle
2276 cc
v3.57 board, MSNS-e 029v, EDIS
Check out my ongoing story.
jsmcortina
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Joined: Mon May 03, 2004 1:34 am
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Post by jsmcortina »

Connect the red wire to switched 12v and the black wire to S2.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
Minami Kotaro
Experienced MS/Extra'er
Posts: 327
Joined: Sun Sep 12, 2004 4:41 pm
Location: Somewhere in TN

Post by Minami Kotaro »

Ohhhhhhhhhh! :D

I see that I have completely misunderstood how the d*** things works yet again! :RTFM: Thank you! :D
1967 VW Beetle
2276 cc
v3.57 board, MSNS-e 029v, EDIS
Check out my ongoing story.
jsmcortina
Site Admin
Posts: 39585
Joined: Mon May 03, 2004 1:34 am
Location: Birmingham, UK
Contact:

Post by jsmcortina »

Compare the summit wiring diagram with the MS1/Extra relay diagram and you'll see why.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
Minami Kotaro
Experienced MS/Extra'er
Posts: 327
Joined: Sun Sep 12, 2004 4:41 pm
Location: Somewhere in TN

Post by Minami Kotaro »

Wow! :shock:

I'm using a 50/50 blend of water and denatured alcohol. Smallest jet that came with the kit, 140psi pump pressure.

~70F ambient temperature.
MAT @ cruise: 120F
MAT @ 13psi without injection: 233F
MAT @ 13psi with injection: 120F

Later, ~60F ambient temperature
MAT @ cruise: 105F
MAT @ 13psi without injection: 200F
MAT @ 13psi with injection: 98F

Double wow! I've added a little timing and leaned my VE all the way back to 100% under full boost to retain 11.5:1 AFR. Duty cycle went down, no detonation, smoother power. I would like to have had an air-to-air for several reasons but there's just nowhere to put it. I'm very pleased with the results of this system so far.

Snow Performance Boost Cooler Stage 1
1967 VW Beetle
2276 cc
v3.57 board, MSNS-e 029v, EDIS
Check out my ongoing story.
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