**MEVI-need help wiring the relay**
11-08-2006, 02:33 PM
#1
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**MEVI-need help wiring the relay**
Hey guys,
I'm about to install a MEVI and I have some questions regarding the installation of the relay. I've read countless threads and have done my homework on this, and understand 95% of what needs to be done to install the MEVI and have it wired up. Unfortunately, many links to pics showing the relay wiring are now defunct. Below, are my remaining questions I have before tackling this project.
FYI, it's a full brand new MEVI kit, including the Harlan RPM switch, the Dawes solenoid, a relay shown in the following pic plug misc wiring etc etc. This is the kit that IanSW put together back in the day. I was lucky enough to stumble across a fellow orger that never installed it and I bought it from him a while ago.
See pics
^^Taken from IanSW's website
^^Taken from the MEVI install writeup on VQPower.com
1. Can someone specifically tell me what wire goes to what on the relay? If you look at the third pic, you'll see five numbers: 85,86,87a,87,30.
I know what to hook up to 85 and 86 based on IanSW's diagram. I need help with 87a, 87 and 30. I don't know how to correlate "output" and "ground" to the symbols and stuff on the relay. (I got a C- in Circuits, that's why I'm a Civil Engineer and not an Electrical Engineer
)
So, output= (insert number here)
So, ground= (insert number here)
2. On Ian's pic, it shows 5 wires attached to the relay, but only using 4 of the 5 connection points??? Is this correct? Two wires (power) go to #85?
3. In pic 3, the only thing that is obvious to me is that 87a, 87, and 30 are a "switch" of some sort. I would think that the flow of the signal would come from 30 and go to 87a or 87, but don't the arrow heads mean the "flow" is actually going the other direction (down in the pic)? Or do the arrow heads mean nothing?
4. Is it possilbe to eliminate the Harlan RPM switch and control when the MEVI opens by using a VAFC, SAFC, or EU?
Any other tips I should be aware of? (besides welding the butterfly screws)
If you guys could help me with this, I would really appreciate it. TIA
I'm about to install a MEVI and I have some questions regarding the installation of the relay. I've read countless threads and have done my homework on this, and understand 95% of what needs to be done to install the MEVI and have it wired up. Unfortunately, many links to pics showing the relay wiring are now defunct. Below, are my remaining questions I have before tackling this project.
FYI, it's a full brand new MEVI kit, including the Harlan RPM switch, the Dawes solenoid, a relay shown in the following pic plug misc wiring etc etc. This is the kit that IanSW put together back in the day. I was lucky enough to stumble across a fellow orger that never installed it and I bought it from him a while ago.
See pics
^^Taken from IanSW's website
^^Taken from the MEVI install writeup on VQPower.com
1. Can someone specifically tell me what wire goes to what on the relay? If you look at the third pic, you'll see five numbers: 85,86,87a,87,30.
I know what to hook up to 85 and 86 based on IanSW's diagram. I need help with 87a, 87 and 30. I don't know how to correlate "output" and "ground" to the symbols and stuff on the relay. (I got a C- in Circuits, that's why I'm a Civil Engineer and not an Electrical Engineer
)So, output= (insert number here)
So, ground= (insert number here)
2. On Ian's pic, it shows 5 wires attached to the relay, but only using 4 of the 5 connection points??? Is this correct? Two wires (power) go to #85?
3. In pic 3, the only thing that is obvious to me is that 87a, 87, and 30 are a "switch" of some sort. I would think that the flow of the signal would come from 30 and go to 87a or 87, but don't the arrow heads mean the "flow" is actually going the other direction (down in the pic)? Or do the arrow heads mean nothing?
4. Is it possilbe to eliminate the Harlan RPM switch and control when the MEVI opens by using a VAFC, SAFC, or EU?
Any other tips I should be aware of? (besides welding the butterfly screws)
If you guys could help me with this, I would really appreciate it. TIA
11-08-2006, 03:47 PM
#2
30 and 87a are connected ar rest. 30 and 87 connect when power is appplied to the coil (85 and 86)
So, output= 87
So, ground= 30
The RPM switch needs its own power supply, and the relay does to. The red wire is connected to both. Splicing it is just easier to do, and niether use up much amperage.
87a and 87 will never connect. At rest 87a connects to 30, but when power is applied to the coil (85 and 86) 87 connects to 30.
The safc will not opperate the switch over. The vafc will using the vtec stuff, EU should with no issue since it has about a million functions.
Dont weld them, loc tite will work just fine.
So, output= 87
So, ground= 30
The RPM switch needs its own power supply, and the relay does to. The red wire is connected to both. Splicing it is just easier to do, and niether use up much amperage.
87a and 87 will never connect. At rest 87a connects to 30, but when power is applied to the coil (85 and 86) 87 connects to 30.
The safc will not opperate the switch over. The vafc will using the vtec stuff, EU should with no issue since it has about a million functions.
Dont weld them, loc tite will work just fine.
11-08-2006, 04:59 PM
#3
you should consider getting a summit switch, vafc, or EU. I had a harlan a while ago and it gave me some problems. If you plan on keeping it be carefull about all the wires it is very delicate hence the need for a relay. I remember having the same problem you are now trying to figure out which wire went where. BTW how do you use the vafc to control the mevi (which one from the vafc and how to actually use it)?
11-09-2006, 08:13 AM
#4
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Originally Posted by JSutter
30 and 87a are connected ar rest. 30 and 87 connect when power is appplied to the coil (85 and 86)
So, output= 87
So, ground= 30
The RPM switch needs its own power supply, and the relay does to. The red wire is connected to both. Splicing it is just easier to do, and niether use up much amperage.
87a and 87 will never connect. At rest 87a connects to 30, but when power is applied to the coil (85 and 86) 87 connects to 30.
The safc will not opperate the switch over. The vafc will using the vtec stuff, EU should with no issue since it has about a million functions.
Dont weld them, loc tite will work just fine.
So, output= 87
So, ground= 30
The RPM switch needs its own power supply, and the relay does to. The red wire is connected to both. Splicing it is just easier to do, and niether use up much amperage.
87a and 87 will never connect. At rest 87a connects to 30, but when power is applied to the coil (85 and 86) 87 connects to 30.
The safc will not opperate the switch over. The vafc will using the vtec stuff, EU should with no issue since it has about a million functions.
Dont weld them, loc tite will work just fine.
Just to clarify. Nothing connects to 87a ever, right?? I guess it just seems weird to me that 30 connects to 87a at rest. If 87a is a resting point per say, then why is there even a connection on the other side of the relay?
In the MEVI faqs, I got the impression that every was using Loctite at first. Then, the consensus switched to welding the screws. I'm interested to hear why you stated to loctite the screws and not weld them.
Your setup looks really nice, btw.
11-09-2006, 03:25 PM
#5
87a is used in other applications. the12volt.com has tons of info if you wanted to know.
When I was on the market for an MEVI, I talked to a few people who gave good reasons to use loctite red over welding. For one the metal is not great to weld since its thin, and you could burn though it pretty easy. Also if you ever needed to take the assembly apart (repair, cleaning, honing, ect.) welding would make it that much harder to get apart. Also the heat generated could warp the butterflies and/or rod. Im not saying its a bad idea its just not the best. I should also state that mine is welded, but I got it used. The people who I talked to who used Loctite red never had an issue. The poeple with the digested screws didnt use anything at all. I havent heard of someone with loctite who lost a screw, but I dont doubt it. Anything is possible. If you know someone who welds and trust them go for it, it will never come apart on you.
When I was on the market for an MEVI, I talked to a few people who gave good reasons to use loctite red over welding. For one the metal is not great to weld since its thin, and you could burn though it pretty easy. Also if you ever needed to take the assembly apart (repair, cleaning, honing, ect.) welding would make it that much harder to get apart. Also the heat generated could warp the butterflies and/or rod. Im not saying its a bad idea its just not the best. I should also state that mine is welded, but I got it used. The people who I talked to who used Loctite red never had an issue. The poeple with the digested screws didnt use anything at all. I havent heard of someone with loctite who lost a screw, but I dont doubt it. Anything is possible. If you know someone who welds and trust them go for it, it will never come apart on you.
11-09-2006, 03:46 PM
#6
Adding something about LocTiting the screws, there are several types: several strengths of the kind you dab onto the machine screw before you install and tighten it, and another variety of LocTite called "wicking" that's intended to draw (or wick) its way into an assembled fitting. DO NOT use the wicking variety. It has its purposes, but this isn't one. I tried it and ended up with some it wicking its way along the shaft into the IM bores, effectively locking up the shaft so it wouldn't rotate. Took about 30 minutes in a 400° oven to effectively "kill" the Loctite so I could get the screws and shaft out and cleaned up.
11-10-2006, 10:20 AM
#7
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^^Thanks for the tip Curt!
Just a few more last question guys before I start the install. I don't drive the car much and often disconnect the battery. Is the Harlan Switch going to "forget" the RPM setting I program?
Is it ok to connect the system to switched power, (only works when key is in/car is running) rather than straight to the battery? or is that the only way the Harlan switch will remember the RPM setting?
TIA
Just a few more last question guys before I start the install. I don't drive the car much and often disconnect the battery. Is the Harlan Switch going to "forget" the RPM setting I program?
Is it ok to connect the system to switched power, (only works when key is in/car is running) rather than straight to the battery? or is that the only way the Harlan switch will remember the RPM setting?
TIA
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