magnumP5's RX-7 Build Thread

[magnumP5]

The flat/satin black Camaros looked pretty sick out there as well (don't tell Mazda I said that). Maybe I should go with a 787B color scheme, LOL!

I tired to update the first page a little (does anyone look at that anymore?). I need to stop forgetting about that. Last night $300 and 50 lbs worth of battery and power supplies arrived so I can got on the battery relocation. There's not going to be too much progress over the next week or so because I'll be out of town this weekend and I can rarely find time to do work during the week anymore.

 

[magnumP5]

No time to work lately. Was out of town last weekend and likely will be this weekend as well. I did manage to find some time last night to start building the battery cables. This is my first attempt at this and I guess the results are okay. I'm not sure I'm too happy but hopefully they work. This heat shrink is rediculously thick! I guess I probably didn't need triple wall after all. My next couple updates will likely be more of this as I need to make four power cables (two 2 AWG, one 4 AWG and one 8 AWG) and at least two ground cables (one 2 AWG and one 4 AWG).

Also, for the battery and main grounds is it okay to just ground to the chassis as long as I remove paint or do I need to use some kind of special grounding lug? I need to find two new main grounding points: one in the cabin for the battery and one in the engine bay for the starter and possibly some other things.

 

[THE Phen]

No special grounding lugs are necessary. Current and voltages aren't high enough to really warrant it. Now, if you were talking about some of the electric motors that I deal with... different story. You'd be fine with chassis grounding. It's all that the manufacturers do anyway.

 

[Lewis7789]

Would you vinyl wrap your 7, Jon? Or paint it? I always like satin black (I want to do my P5 too) but that flat grey is sweet too. And yay for progress! And indeed keep your first page updated. When someone new to your build thread checks it out they won't have to read all 34 pages. It's like crib notes. haha

 

[magnumP5]

Would you vinyl wrap your 7, Jon? Or paint it? I always like satin black (I want to do my P5 too) but that flat grey is sweet too. And yay for progress! And indeed keep your first page updated. When someone new to your build thread checks it out they won't have to read all 34 pages. It's like crib notes. haha

I'm not sure on the wrap vs. paint as a decent wrap job is probably just as expensive as any paint job I'd be looking to get. The benefit with the wrap is I could go with whatever color I wanted whereas paint would be limited to red. The original red is called blaze red, but I'm also considering classic red from the P5 and true red from the newer Mazdas...

I'll try to keep the first page up-to-date but it's hard when I have like 200+ pictures of progress, and even then new readers wouldn't get to read my rambling commentary...

Still working on wires. I've gotten the primary power and ground cables made and now I need to run them to the engine bay and figure out where to mount the breakers. I also need to make new alternator and starter wires but right now they're not essential to testing the system. I also need to wait for a few more electrical goodies.

I'm debating installing a fuel pump cut-off switch. Rebuilt rotaries are notorious for having low compression initially so they tend to flood easily. If I do install one I can install the switch on the injector circuit or the fuel pump circuit. The former, if off, simply won't allow the injectors to fire so the engine wouldn't start. The latter, if off, will still allow the engine to start if there's fuel in the lines but it would quickly die if the fuel pump weren't switched on.

 

[magnumP5]

Got the main power wires completed today. Plugged everything in and all systems are go! The warning buzzer went off, which I'm sure is a result of not having the coolant level and or oil level sensors plugged in so hopefully that will stay off once everything is put back together. I guess I can always ground the wires to make sure. More updates/pictures on Monday...

 

[magnumP5]

Some teaser pics of the batter relocation because I spent too much time fiddling with other things to go out and take more pictures.

Here's the power wire routing inside the cabin. 2 AWG wire goes along the driver's door sill into the engine bay to another circuit breaker, which is held by metal screws drilled into the body. the 8 AWG wire goes along the passenger's door sill up into the kick panel to the fuse panel, which powers the ECU, injectors, ignitors, fuel pump and gauges. The more I look at the three-walled heat shrink tubing the more I dislike it. If I can some some single-walled black stuff lying around I'll cut the three-walled stuff off and use that instead...

In the engine bay the 2 AWG wire runs to another breaker at the base of the strut tower. I used an existing threaded hole so no drilling here. A new 4 AWG wire is used to power the fuse box. Ultimately there will be another red 2 AWG wire running to the starter from the breaker and a black 4 AWG wire running from the fuse box to the alternator. The relay next to the fuse box is for the electric fan. I'm still not sure if I like it there or not.

In other news I finally picked up my ported intermediate and rotor housings. These things looks great; I will post pictures later. I'm currently in process putting the interior back together. I probably would have had the dash in by now but I guessed wrong on the lengths of the wires needed for the gauges so I have to go back and extend all 15 of them.

 

[PrinceValorum]

Are you planning on putting the battery in a sealed externally vented box, or is it a type that doesn't require that?

 

[magnumP5]

Are you planning on putting the battery in a sealed externally vented box, or is it a type that doesn't require that?

The current battery would require that (lead acid-filled) but I plan on getting a smaller solid or gel-filled battery that does not require sealing. Note the battery is also just sitting there. In the end I'll have some kind of bracket/support structure in there.

 

[magnumP5]

I decided to buy a few things for the interior so reassembly is on hold until they come in. In the meantime, photo dump!

Some pictures of the porting work. First the intermediate iron:

Next, the rear iron (front is the same port):

Exhaust port from the manifold side:

Exhaust port from rotor side:

Lastly, all in one!

I will be painting all the pieces with high-temperature primer, paint and clear. The irons will be painted a color called "cast iron" and the rotor housings and all other aluminum bits, "cast aluminum." Very original, I know.

Next, I got bored waiting for parts so I decided to do something about a mistake a made when taking the dash out. This is what happens when you aren't careful around plastic that has been exposed to sunlight for nearly 23 years.

Since I have no reason for these defrost vents (and I don't want to spend $20/each on new ones) I decided to make some block-off plates with my ever-useful sheet of .025" aluminum. Trace vents and cut...

Test fit:

I'm in the process of priming, painting and clearing them now. I'm debating doing the same thing with the vents that run along the front of the windshield.

Lastly, a question. Would using 4 AWG wire for the starter power and ground be a bad idea? I have 2 AWG wire running from the battery to a circuit breaker (>18") and then to another breaker in the engine bay. The breaker will act like a splitter for the power wires to the starter and the engine fuse box. The latter is fed by a 4 AWG wire and I want to use the same for the starter as the smaller wire is more flexible and easier to gang on the breaker. Would this diminish the power to the starter so I should keep the 2 AWG plan?

 

[PrinceValorum]

Since I have no reason for these defrost vents

Are you gutting the blower motors, too? I'd be worried about it fogging up on cold track day mornings. Just keep a towel in the cabin, I guess.

 

[fishdonotbounce]

Jon, have you seen justanothermp5's DIY full car wrap? He's in the process and has said that itcosts approximately 400 for everything including tools. Also says its really easy, though time consuming.

 

[magnumP5]

Are you gutting the blower motors, too? I'd be worried about it fogging up on cold track day mornings. Just keep a towel in the cabin, I guess.

I left the blower motor in place. Without A/C or heat would the defrost vents really be usefull at all? But yeah, cold track mornings would pretty much be the worst for fogging up.

Jon, have you seen justanothermp5's DIY full car wrap? He's in the process and has said that itcosts approximately 400 for everything including tools. Also says its really easy, though time consuming.

I think I read something about him doing that. In all honesty I don't really follow too much of his stuff. For the most part I'd think a vinyl wrap would be pretty easy on the RX-7 as it's got some pretty straight, square lines. The trickiest parts would be the mirrors, spoiler (I may remove that), door handles and side moulding pieces (I can't remove mine w/o it looking strange). Paint or vinyl wrap, either way would still require some amount of body work to fix some rust spots and the larger dents. $400 isn't bad though.

 

[PrinceValorum]

I left the blower motor in place. Without A/C or heat would the defrost vents really be usefull at all? But yeah, cold track mornings would pretty much be the worst for fogging up.

I dunno, I'd think air blowing over it would be better than nothing. Maybe not?

Forget vinyl, leather wrap would be baller.

 

[magnumP5]

I dunno, I'd think air blowing over it would be better than nothing. Maybe not?

I'm not sure. I decided to try to make covers for the window vents last night anyway. The shape is a little more complex so I figured if they turned out poorly I'd just leave the vents. So far they look pretty good (in the primer phase) so I'll keep working on them. While there really isn't any weight savings it really does open up space behind/under the dash without all the plastic tubes running around.

Forget vinyl, leather wrap would be baller.

"Vinyl wrap? My car is wrapped with dead cows!"

I'm still working. The biggest task right now is figuring out how to mount the new coils. I want to keep them all together but they're huge!

 

[R-X-R]

lookin good., this give me some idea for mine .,.,.will u be doing the taurus alt swap?

 

[magnumP5]

lookin good., this give me some idea for mine .,.,.will u be doing the taurus alt swap?

I'm not familiar with this swap. I know the S4 guys like to step up to S5 or FD alternators, but considering I already have a S5 and I've removed a lot of the items that put load on the alternator I don't think I need to upgrade.

Does anyone know if you can determine the current capacity of a relay w/o destroying it? I want to reuse one of the stock relays for my electric fan because it has a rubber cover to protect it from the environment and my new one does not. It's going in the engine bay near the front of the car. I think it may have been the foglight relay but I need something that can support up to 30 amps.

Also, I'm done with the vent block-off plates. Pictures later today when I get home.

 

[THE Phen]

Track the part number. That's really the only good way to find out what the capacity is. I do believe that the majority of automotive relays are around 30A

 

[Wagonbacker9]

Track the part number. That's really the only good way to find out what the capacity is. I do believe that the majority of automotive relays are around 30A

if it is a full size, almost certainly. Lower capacity are almost always smaller.

 

[magnumP5]

Track the part number. That's really the only good way to find out what the capacity is. I do believe that the majority of automotive relays are around 30A

That's the problem. The P/N isn't marked from what I can tell and I can't remember if it was the foglight relay or the A/C relay. I guess since I have a backup that I know if rated 30A the worst thing that could happen is I fry the existing relay and have to replace it.

Also, I may have asked this earlier but would there be an appreciable difference in starting "power" if I used 4 AWG to wire the starter versus 2 AWG?