magnumP5's RX-7 Build Thread

[mymmeryloss]

Updates?

 

[magnumP5]

Updates?

Really not much of anything. Work has been kicking my ass and the few chances I get to work out it are wasted scratching my head trying to figure out the wiring harness.

I've decided to build the Sprint RE harness myself rather than spend $400 to have someone make it for me. I've got 90% of the parts I need and I've easily spent $200 in misc electronics. What I'm trying to figure out now is how to mount the ECU, 4 relays, a fusebox and the dual channel wideband controller. At first I figures I'd just put the Sprint RE where the original ECU was and mount all the relays and fuse box by the passenger's feet. Like the Protege, the ECU is mounted on a metal bracket beneath a (sharp!) metal cover:

With some clever mounting I found I could use the stock piece with the Sprint RE. LOL size difference!

Since that picture I've determined there isn't enough space by the passenger's feet for all four relays AND the fuse box. So what I'm going to do is take a sheet of .025" aluminum and make a flat plate to bolt onto the mount shown above to hold everything.

So while I scratch my head trying to figure how to mount everything on the aluminum plate I've been playing with the engine bay. Test-fitted the new radiator to check wire clearances:

Added the crank angle sensor (CAS) to the dummy engine build and started test-fitting the temperature/pressure sensors.

It's hard to tell from the above pictures but I'm basically replacing all the stock connectors in the engine bay with GM-style Weatherpack or Deutsch style connectors. This is this is so oddly fascinating to me I go out of my way to replace something.

Not pictured is my new 16", 3000 CFM electric fan. I'm still debating whether I want to build an aluminum shroud for it or not. I'm also still waiting on the housings/irons from the machinist. They ran into some problems with the front iron so it had to be replaced Fortunately they had one in good shape lying around

That's all for now.

 

[Lewis7789]

I don't know why but I've always had a thing for radiators and cooling systems. And that radiator is badass. Making good progress, Jon. You're doing it right. I like that mentality like the old hot rod guys have, a build could take them 3-4 years and they're in no huge rush. I just can't wait to see it in person when it's all done. You're going to just fly in HPDE's. (2thumbs)

 

[PrinceValorum]

I appreciate all of the planning and effort that's going into this build.

 

[magnumP5]

Got a little more done last night. Figured out the ECU/relay/fuse box configuration. No matter what I tried I couldn't get all three in the same location so the fuse box is going behind the passenger's kick panel and the ECU/relays will go in the stock ECU location. I started to lay out the ECU and relays (yay cardboard!). Note that I also cut off/grinded down two extraneous studs and the two wire clamps at the bottom:

Here's the convenient metal plate that fits behind the passenger's kick panel. The fuse box (I guess it's really a fuse panel) will be mounted as shown. Power will be supplied by a 8 GA power running straight from the battery (now behind passenger's seat) and the fused wires will then all run to the ECU and relays.

For giggles, here's the electric fan with my hand as a reference. Note the Weatherpack connector used as well, LOL!

I also found a good source for MIL-Spec wire to use. Not that I really need MIL-Spec wire, but it's the only place I could find that sells multi-colored wire or wire in spools of less than 100 ft. Now begins the tedious task of figuring out how much of what color/size wire I need for each application. The goal for today is to get all that wire ordered and to have the ECU, relays and fuse panel mounted.

 

[magnumP5]

More slow progress...

Got the ECU, relays and fuse panel all mounted last night. Picked up a 24" x 24" .025" aluminum sheet to mount the ECU and relays to the stock bracket. I only needed about 9" x 9" so now I have plenty to spare for othe projects

First, cut to shape and drill holes. This is the first time I've used my metal shearers in a long time. Also admire our awesome tiled kitchen floor! Why I was doing this in the kitchen I don't know...

Measure a bunch of times, drill some more holes and cut off some pointy edges and you get the following:

The fuse panel was much easier. Since the stock metal piece I am using is thicker than the aluminum sheet I just used some metal screws:

Ignore the terminals. They were they to check clearances. It'll be tight but everything should work just fine. With those pieces done it was time to reinstall into the car:

The ECU, relay and fuse panel wires will all run along with the wire already in the car. Next the flying lead ECU harness goes in. I should also have my gauges back today so hopefully by the weekend I'll have just about everything where it needs to be to get an idea of how much additional wire I need to buy. I ordered the water temperature and intake air temperature sensors for the ECU and four coils/ignitors on Wednesday so at this point the only sensor I'm missing is the TPS. I need to have the throttle body because the TPS's are clockwise/counterclockwise-specific.

 

[o0n8]

everything looks amazing, I hope I have this much patience when I start on my camaro project. I kinda ran out a couple of time with my msp and I think it shows. Keep up the great work!

 

[Lewis7789]

Are you going to have an additional kick plate over the ECU and fuse blocks? Are you going to gut your RX-7 and just leave them exposed? Just curious.

Again, keep up the great work, Jon. This is one of my favorite build threads to follow.

 

[magnumP5]

everything looks amazing, I hope I have this much patience when I start on my camaro project. I kinda ran out a couple of time with my msp and I think it shows. Keep up the great work!

I know what you mean. There were a couple times with my P5 that I cut corners and it always kind of bugged me. It's funny because back then I'd skip breakfast/lunch/dinner, work to 1, 2 even 3 AM on the P5 just to get something done. Nowadays I find myself taking breaks for food, working only a couple hours a day and just generally at a slower pace. Maybe I've matured and realized everything doens't need to be done now, now, NOW! Then again, maybe it's because I'm married, LOL!

Are you going to have an additional kick plate over the ECU and fuse blocks? Are you going to gut your RX-7 and just leave them exposed? Just curious.

Again, keep up the great work, Jon. This is one of my favorite build threads to follow.

Yep, there's a thick aluminum kickplate that'll cover the ECU and relays. It'll go back one one I'm done with the wiring. I still plan on having *most* of an interior when I'm done. I'm debating leaving the hatch area gutted but the front will still have carpet, etc. Since I'll be in HPDE for a while I don't see a reason to completely gut the car just yet

I don't think I've said this before but I really appreciate you guys following and commenting on this. Generally I don't see anything too amazing about the car or my work so it's nice to read other people's opinions. It'll be a cold day in hell before my wife starts supporting this hobby and somedays my resolve alone just isn't enough to keep me motivated.

 

[magnumP5]

Just one picture today. Finally got the correct gauges in. I really love how they work. Simple, yet very high quality:

I started laying everything out in the car last night. What I'm trying to figure out now is what to with all the ECU leads I won't be using. Even with the Sprint RE I'm using so few features that I only need about half the wires included in the harness. Right now I have those I won't be using coiled up in a little bundle alongside the ECU but it takes up a lot of space and weighs quite a bit (8.5 ft of about 15 wires). I'm not sure I want to cut them just in case I decide I want to use those features later on. Any ideas?

 

[PrinceValorum]

Right now I have those I won't be using coiled up in a little bundle alongside the ECU but it takes up a lot of space and weighs quite a bit (8.5 ft of about 15 wires). I'm not sure I want to cut them just in case I decide I want to use those features later on. Any ideas?

Since you're not gutting the whole thing now, I'd leave them until you come to that bridge. I doubt the few lbs of wiring will be that noticeable, especially when you've got other things like carpet and stuff, ya know? It's always easier to cut them off later than to solder more back on later. At least that's how I'd approach it.

 

[magnumP5]

Since you're not gutting the whole thing now, I'd leave them until you come to that bridge. I doubt the few lbs of wiring will be that noticeable, especially when you've got other things like carpet and stuff, ya know? It's always easier to cut them off later than to solder more back on later. At least that's how I'd approach it.

I decided to keep them bundled and stuff them under the ECU mounting plate. As long as I keep the wires insulated I don't think it'll cause a problem.

I did manage to get some work done over the holiday weekend when I wasn't doing housework with the wife.

I went ahead and made a harness for the gauges and spliced into existing wiring. It uses the same switched 12V, ground and illumination source as the stock gauges. I was a little off on some of my wire measurements but I suppose it's better to be long than short.

To access/set the peak recall and warning features of the gauges they each come with a button. I wasn't sure I'd use them at first or even where I'd put them if I did use them but I decided to mount them where the AAS switch used to be. Used the same .025" aluminum to make a blank cover where the foglight switch used to be as well. I moved the security light to the passenger's side in case I decide to use the blank for something in future. I'm in the process of painting them black like the gauge panel.

Wired the dual wideband gauge in the same manner as the other gauges The electrical tape covers the spade connectors (!) to prevent a short. I used spade connectors because the gauge itself didn't come with any terminals and I couldn't find any 5-pin connectors that were small enough to fit in the area around the steering column.

I decided to mount dual wideband controller in the glovebox. It needs periodic "free air adjustment" so it has to be located somewhere accessible and I'd rather not put it in the engine bay. I really need to get a rubber grommet for that hole.

I got a lot of wiring in general done over the weekend. I'm currently stuck while I wait for more wire, terminals, etc. to be delivered. The cabin is about 80% wired at this point. It's messy as hell but it everything will be cleaned up before the dash goes back in and once I've confirmed all circuits are still working.

I also ran wires out into the engine bay. These likely won't be terminated for some time as I need an intake manifold, throttle body and fuel rail before I can do anything with the TPS, IAT and injector sensors. I suppose I can wire the CAS though.

Last, but not least, the new coils. Currently have 3/4 needed. Now I need to figure out how to mount these things. They're a lot bigger than I thought!

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[hat1018]

Looking good Jon. Keep it up.

 

[mymmeryloss]

I'm super jealous!

 

[magnumP5]

Not really an update and no pictures but little progress has been made. I had to wait while new wire and supplied were ordered and shipped. I think I have all the electronics I need except the battery relocation stuff. I finished wiring the relays last night and started cleaning everything up. I was surprised how stiff Mil-Spec wire is! All I need to do is wire in the dual wideband controller, run the power wire for the new fuse panel and get the battery relocation sorted out and I'll be able to test the wiring for the first time!

 

[magnumP5]

As those who were around me on Saturday know I think I've managed to get the interior wiring done. The only thing missing now is power. I want to make absolutely certain everything works before putting the interior back together. Onto the pictures...

Shot of the driver's side and gauges. Getting the fuse box (not pictured) and all the wires behind the driver's kick panel back together was a PITA!

And the passenger's side.

A closer shot of the ECU and relay mounting plate. The three female spade connectors are for the dual wideband controller, which I mounted in the glovebox so I can route those until the dash is back in.

Lastly, my finished "switch" panel. These are the buttons for the peak recall and warning features for the gauges and they'll sit right between the armrest and the shifter.

Of course as I'm "done" running wires for the interior I'm now wondering if I should have deleted the stereo and speakers and all the associated wires. I haven't really figured out how to mount the radio and I'm thinking it's probably not going to get a lot of use. I'm really not wanting to go in there and remove everything again...

 

[Lewis7789]

Good to see you again, though briefly, this weekend, Jon. And congrats on the Mazda2, you sneaky bastard. Haha

 

[mymmeryloss]

All of this wiring is really making me nervous...

Makes me realize how little I know about this stuff!
Can I fly u down to wire my truck!

 

[magnumP5]

All of this wiring is really making me nervous...

Makes me realize how little I know about this stuff!
Can I fly u down to wire my truck!

Having a FSM really helped, but I guess that won't do much in your situation. I was really nervous at first, which is why I tackled some smaller stuff first to test my confidence before moving to the dash and the engine bay. Fortunately I could generally follow the factory routing in the cabin, which took out a lot of guess work, but the engine bay is a whole different story. The big test will be when my $300 worth of battery and power supplies come in and I can finally charge everything up and make sure everything works!

But yeah, outside of Ohm's Law I really don't understand too much about wiring and electricity. Based on the patience and diligence you've shown in your build thread I don't think you'll have any problem picking it up though.

So yeah, as I mentioned above the only update I had is that I ordered $300+ worth of battery and power supplies. That should be enough for me to complete the battery relocation and all new wiring. Once I've tested and confirmed all the remaining electronics work the next projects are depowering the steering rack and figuring out how to mount the coils/ignitors.

Oh yeah, after watching the Continental Tire series this weekend I've really started thinking about paint. Kinetic Motorsports had an awesome looking M3 with this sort of satin grey paint job. It was just shiny enough to not look like primer but flat enough to look unique. I've also been toying with satin black and Mazda's True Red (like the 2!). Any feedback?

 

[THE Phen]

Kinetic's car is freaking cool. Gotta love vinyl wrap. However, the front fenders looked like they got a bit mangled and replaced.