So, I'm ready to drain my fuel tank, add new fluids and fire her up. I only have one question, really I just need confirmation that this relay setup is ok. I upgraded to the S5 alternator, so the black w/white stripe wire is no longer used. Now according to the schematic, this is 12v with ignition on. So I'm using that as the control to open relay one, and the 12v off that to control relay 2 going to my 3 coils positives on DLIDFIS setup. Does this look ok? I can't afford to fry my setup, and would like to get it fired first time with no electrical ghosts to chase.
Here's a drawing of how I wired it up so far.

 

first off, when a relay is energized, it closes the circuit. 2nd, there's no reason to use one relay to control another. and 3rd, why? the ignition switch controls the power to the coils. so why 2 or even 3 switches to do what 1 does sufficiently? relays r usually 30a and used to control a pair of driving lights or an e-fan, something that draws alot of amps, to protect the switch from burning it up. the relay takes the amp load rather than the switch.

 

1. When the relay recieves power to 86, it closes the circuit between 30 and 87. Thereby "turning on power to 87.

2. I deloomed and removed all the original ignition wiring and coils. I'm running a custom DLIDFIS setup as stated above.

3. I don't want to run my fuel pump and my coils off thr same switch/fuse. I'm only using the power on one to trigger the other. That way I keep two seperate circuits with seperate fuses.

4. Would you really suggest I run 3 coils and an aftermarket fuel pump all on the same fuse/relay/switch?

 

many have done the dfis upgrades with great success without having to do what ur contemplating. but hey, it's ur car.

 

Sorry for not including all the info, was trying not to write a book. Background ...
Motor is a 12 N/A w/weber sidedraft. I found questionable wiring done by the PO, so I opted to feloom and remove all non-essential wires. At the same time, since the motor was toast and battery tray rotten, I opted to relocate the battery and upgrade the ignition to DLIDFIS w/HEI modules. I'm going to be converting to power windows and locks as well as a proaudio sound system and a Taurus e-fan, so I also decided to upgrade to an S5 alternator and a 2nd gen. fuseblock. I also upgraded my fuel delivery system with a "Holley red" type fuel pump and a regulator w/gauge. Obviously the stock wiring was not going to be adequate for all my needs, not to mention the mess the PO made of it. I made my own ignition box w/modules and modded my dizzy w/weathertight plugs. I ran new wires from my optima battery (now behind drivers seat in bay) to the starter and the alt., ran wires for my fuel pump to the fuseblock, from igniters to coils, tach wire off trailing coil and removed fuseable links and installed fuseblock. Installed the S5 alt. which doesn't use the black w/white wire that is energized on ignition, it only uses a jumper from one terminal to the + and the signal wire for the dash indicator. I needed a "trigger wire" for the fuel pump and the coils, so I figured instead of running more new wires, I would use the alt wire with a couple relays to provide higher current power to the coils and fuel pump. The relays are 40 amp, and the power supply is off the fuseblock, a 30 amp to fuel pump and 40 amp to coils. Fuseblock is powered off a new battery lead from the starter post. Now, my question is, since it seems to be a bad idea to run the wires as I'd originally drawn up in the pic. Is there some reason why I shouldn't use the low voltage wire from the old alt. to "energize" both relays, providing current to the pump and coils? I'm not looking for opinions on whether I should have chosen different upgrades etc. Just advice and info on the best way to do what I'm trying to do. This is my first rotary, and all these upgrades are a first for me, so I've researched and studied for almost a year before I actually did any work. I chose to do all the upgrades at once rather than 1 at a time. I'm basically done at this point, but before I attempt to fire her, I wanted advice from some of you that have actual "experience". I learned long ago that "knowing" how to do something and actually doing it are very different, and "real world" applications and experience are valueble tools. If you can help me out, or add pointers etc. I'd appreciate it. If you want to tell me i'm an idiot or chose the wrong mods etc. don't bother. I know it's my car and can do what I want. But I'd also like to do what I want "correctly".

 

i'm not saying ur an idiot. not saying it wont work, just what ur wanting to do with the relays isn't necessary and the time spent doing it could be better utilized elsewhere. that alt wire can be used to provide switched 12v for the coils and the pump if u wish. but what u said about wiring a couple relays to provide higher current power to the coils and fuel pump, a relay doesn't increase the current of the circuit it's added to. relays reduce the amperage a switch sees. just seems to me u misunderstand what a relay does and how they're used in a circuit. now as for ur drawing of wiring them, i don't remember off the top of my head which terminals r which on the relay without using the diagram on the box it come in. and i don't have one handy to check ur drawing with. i do wish u the best of luck in ur endeavors.

 

I apologise if it sounded like I was directing all my comments at you in particular. You just happened to be the only person to respond. I noticed often times as much effort seems to be put into critisizing the poster as is put into offering constructive advice, so I was attempting to keep the "Duh!" type comments to a minimum. Turns out I have other electrical issues anyway. I shoulda just ripped it all out and made a new harness altogether. I connected my battery and I have no power to the alt. wire I'm attempting to "use" with the key "on" anyway. I also have a freakin buzzer going off under the dash somewhere as soon as I connect the battery! ARGH! Since the car isn't running, I'm assuming the buzzer isn't the seat belt, what other buzzers are under the dash?

 

there's an over rev buzzer but i think that's attached to the tach. there's one for the reminder for key in the ignition when off and the door is opened(new cars "ding"). probably others but those i'm currently aware of. if the wiring is that FUBAR, have u considered a harness from painless wiring? if u haven't already done it, there's downloadable versions of the FSM in the 1st gen archives: http://foxed.ca/foxed/index.php?page=rx7manual. download the manual that suits ur model.

 

Already have the FSM, Haynes and Chiltons, Wiring schematics, Wankel book and a couple others. Found the alt wire problem. Loose wire at a junction connector. I feel like an idiot, but I found the buzzer too. It was the damned door. It buzzes ANY time the door opens, till it's closed, key out or key in. I'll be locating that and disconnecting it for sure! Irritating as hell. Got the relays straightened out, fuel pumps pumping and coilos are getting juice, but by the time I got around to trying to start her, the damned battery didn't have a good enough charge. So, she's charging now and I'll try her later after work. Thanks.

 

mazda acutally uses the dual relay setup on the Efans, i think it gets rid of a potential ground loop, or something.

also splitting the power like that SEEMS like a good idea.

mine is an 82, so i'm not sure how different it is, but on mine the battery goes to the main fuse, and then the fusebox under the dash.

so essentially the power all comes from one place anyways, not that things like the fuel pump and ignition couldn't use "better" more stable voltage.

i guess if your harness is no good, then why not...

 

First off, the way the relays are connected may not be the best
for the life of the coil relay. Your switching the relay for the coils
on/off with the output that drives the pump and that higher
amperage will/may shorten the life of the relay. So you may as
well condition the coil relay with the signal from the alt as well.

I would just tie 85 from the pump relay to 86 of the coil relay and
poof your done.

 

This would be a smarter way of wiring them... assuming that the black/white alt wire is switched +12V when ign is on. You could also include some flyback diodes, but it wont matter too much.

Also, since there seemed to be some confusion. A relay is used to allow a low current signal to control switching of a possible higher current signal. Yes, they are used to allow lower current through a switch to trigger a higher current power source, but they can also be used to allow a power source such as the alt wire to trigger a higher current power source like a fuel pump supply, allowing a higher gauge wire, and thus a higher current to be used, direct from the battery or whatnot.

Splitting the circuits into two circuits is a good idea. It slipts the load on the relay and also keeps things separate.

Although its a odd way he had them wired, this technically is not going to harm anything. The relay will not be harmed by the "higher current line". The relay will not draw the same amperage as that of the fuel pump. It is however an odd way of wiring them.

 

Once my brain engaged, the same thing occurred to me. And that is precisely the way I did wire em up. Works like a charm too. Thanks!