Mushiki

Hello everyone,

Here's the thing... I have a pretty "special" NA FC, it's a model that was sold in parts of Europe, the Middle East and New Zealand.

It has a S5 body, but mechanically it's a bizarre mix of parts:

- NA S4 6-PI engine
- NA S5 Aux port sizes
- Electronic Distributor (same as in FB's)
- N368 ECU (S4 connector, only controls fuel)
- 12V AFM (instead of a 5V one)
- ECU/solenoid-controlled butterfly valves instead of backpressure-operated rotating sleeves for the 6-PI system
- No MAP or O2 Sensors

So I want to make it more like a "normal" NA S4, by getting in some S4 parts...

I assume I would need the following:

- NA S4 ECU
- NA S4 Engine Harness
- CAS
- FC Coils
- 5V AFM

What about the MAP and O2 sensors? I was wondering... considering that many emissions-related engine accesories can be removed... what do I NEED to perform this ignition swap appropriately? I plan to remove as much stuff as possible.

Here you can see some detailed diagrams on the differences:

"Inputs" -- All items marked with "*1" are items we find in normal FC's (unlike mine), and all marked with "*2" are exclusive to my type of FC




The typical fuel/ignition diagram for a normal FC




The diagram for my kind of FC




Exhaust differences -- "Australia" would be a normal FC's, while "Except Australia" is like my FC's exhaust




Standard FC's vacuum diagram --




My FC's diagram --




Well... I think that's it.

Any kind of help/feedback will be immensely appreciated



Regards,
-Dan

Pele

iTrader: (28)

The ignition setup is similar to the GSL-SE and 1981-1985 12A powered First Gen RX-7...
It is fully electronic, as there are no mechanical points.

Head over to the 1st gen section and lookup DLIDFIS; Stands for "Dual Leading Ignitor Direct Fire Ignition System."

What this will allow you to do is run your stock ECU and ignition components with an FC Leading coil. The FC leading coil will have plug wires that go STRAIGHT to the plugs.

You may then transfer your stock trailing wires from the lossy trailing section of the cap to the more efficient Leading section of the cap.



Here's the problem with what you're doing:

You will need the power harness from a US spec FC as well. You'll need to remove the dash to get it out. It'll be much more trouble than it's worth.

I wouldn't worry too much about the trailing ignition, as it doesn't do as much since the leading will have "wasted spark" firing. (Ignition fires on the exhaust phase of engine running.)

You'll gain the direct fire ignition (More power to your plugs) with the wasted spark (More efficient combustion)... But it'll be MUCH easier to build and it'll allow you to go back to stock if a component fails on you on the side of the road. Plus you won't be shipping half of a US spec car from a foreign country. All you need is a leading coil from a US spec FC.

Mushiki

Ohh... the power harness thing sounds like a mess...

So it's not worth it?

Wouldn't this ignition setup be much better?

arghx

iTrader: (3)

The normal EFI system uses actual electronic spark advance. It's a much better design in all aspects versus distributor... spark advance is determined by the airflow meter signal, the crank angle sensor, and the engine operating condition. On the S3 and your weird s4 the computer just cuts the vacuum advance under certain conditions. It's far from optimal. The normal FC also has proper sequential fuel injection (versus batch fired injection on your middle east spec) with closed loop o2 sensor feedback. There should be some improvement in fuel economy from this, at least on paper.

If you switch to a "normal" FC fuel injection system you can run an Rtek 2.1 and then you can tune fuel and spark timing. You could also use the switchable output to control your 6 port system. BUT... it's hard to be certain of the real world benefits vs. the hassle of collecting everything you need and then ripping the car apart.

Mushiki

So you believe it would be too much of a problem?

Other than the whole power harness, would I be missing anything else?

Remember, my car has no MAP or O2 sensors

SirCygnus

iTrader: (1)

why not just get a haltech?

Mushiki

A Haltech and?

Money is also a "problem" here.

arghx

iTrader: (3)

No matter how much better the "normal" FC fuel injection system is, it seems like a lot of work for minimal real world benefit. It's still a 16 second car in the 1/4 mile and fuel economy will still suck by today's standards. Maybe you should just enjoy the car for what it is and focus on maintaining it.

The same arguments could be said about a Haltech on an n/a engine. No matter how you slice it, it's still slower than a V6 Camry with the fuel economy of a V8 pickup truck. Handling is still great but the engine potential per dollar is too low... there's not much sense in trying to make the car something it's not.

Mushiki

The thing is, I am planning on doing extensive modifications in the future -- and considering how rare this cars are I thought of making my car as similar as possible to US FCs.

If I plan to run a standalone (Haltech PS1000), wouldn't I need a CAS? a full engine (and power?) harness?

I'm trying to face this project in stages, instead of going all out in a single one.

Mushiki

Still... now that I think about it, not even the fuse boxes are the same...

And my car's alternator is a S5 one, those that have the exact same connectors that FD alternators have

There's probably a lot of wiring to do

arghx

iTrader: (3)

Why don't you figure out where you want your car to be down the road? Do you plan to go turbo or not? That's a huge factor

Mushiki

My car is working right now.

I am planning on getting a rebuild + streetport (Intake: Pineapple Racing 6-port Large Streetport template, Exhaust: Pineapple Racing EP2A template) in a couple of weeks.

I was considering getting this done while it was being rebuilt.

Turbo? Not at all, in the long run, this is my planned setup:

- Streetported Engine
- OMP Removal
- Individual Throttle Bodies
- 2x Injector Dynamics 1000cc Injectors
- Walbro 255 Fuel Pump
- Custom True-Dual Exhaust
- Haltech PS1000 EMS

Other than that, some other things probably not worth mentioning like a better clutch, lightweight flywheel, LSD, coilovers, etc.

Pele

iTrader: (28)

You'd be replacing all the wiring in the engine bay.
You'd be importing parts.

When the car breaks down on the side of the road (It will... All mechanical devices fail at some point or another.) will you be able to get US Spec parts as easily as your car's original parts?

I'd say the swap is not worth it.

Run the updated ignition system. It's easy enough to add and allows you to go back to factory when needed.

It will give you:
-Stronger spark (Not going through the distributor cap)
-Cleaner exhaust (Fewer unburned hydrocarbons out the tailpipe)
-Slightly longer power phase (By a few degrees... Maybe.)

I dunno, all the benefits will be in the DLIDFIS threads.

Minor work for some decent gains.

Mushiki

Mazda basically doesn't exist in Argentina, so I ALWAYS have to import parts when something breaks down.

Where can I import parts for a FC that "doesn't exist" according to Mazda or any aftermarket vendor?

Everything I buy for this car is mixing+matching stuff from different FC's and FB's... it's a ******* PITA

arghx

iTrader: (3)

save your money and when it's time, go right for the Haltech. You will have to rewire your car for that anyway. Yeah you'll need a crank angle sensor but you wouldn't be using the factory sensors for anything else. You can run four GM LS1 style coils for the ignition when the time comes.

Why waste time and money on this? There's doing things in stages and and then there's wasting time and money by doing something and then almost completely undoing it. With a Haltech you will want to replace all your sensors anyway except the CAS.

beefhole

iTrader: (29)

^ Agreed to get it all/do it all in one shot. Also you need to know if there is ANYONE who even knows the haltech/tuning to make your car run. Now if it's an NA, you should be able to find a basemap and be safe from blowing up. However, it may not end up being optimal and performance can suffer.

Aaron Cake

iTrader: (1)

These are just may crazy random ramblings, which may or may not have much to do with this thread...

I've always found it curious how Mazda used cats in some markets and the old thermal reactor in other markets. But if you think like Mazda, it almost makes sense. Less strict emission standards mean that they can use the old and thoroughly developed thermal reactor system. Then markets with stricter standards get far more expensive cats.

The reason they kept the dizzy is likely because the whole thermal reactor setup was lifted from the 1st gen, where the ECU cut spark at different points to get raw fuel into the reactor. It was probably easier to stick with the dizzy and use a box similar to the 1st gen "ECU" (really nothing but a bunch of relays) and then use the GSL-SE setup of a fuel only ECU to run the injection. Far cheaper then coil packs, CAS, catalytic converters, etc. What is interesting however is that they chose to cast a new lower intake manifold. Because of the massive size of the thermal reactor manifold, the aux port actuators won't fit on the outer side of the manifold. So they moved them to the top and used throttle butterflies instead of slide valves. Quite interesting. Also notice no O2 sensor with the thermal reactor, of course. O2 correction can't work due to the huge amount of air being supplied to the exhaust via the air pump.

The thermal reactor really was a good system, but very heavy. Far less prone to damage like cats and very effective at reducing pollution. The rotary inherently produces far more hydrocarbons and far less NOX, so all it takes is to burn the hydrocarbons in a reactor. Mazda was able to fly through emission standards for years while other manufacturers struggled. Also, the exhaust from a thermal reactor just smells....nice.

Sorry, I have thermal reactors on the brain because I just started pulling the engine on my '76 Cosmo and was thinking about the system as I was removing it. Also, I like saying "Thermal reactor". It sounds so sinister. "Respect my rotors or I will unleash my THERMAL REACTOR!".

Anyway, I think the OP should just leave everything as it is if he has plans to go to a standalone in the future. Since all that stuff will have to come off anyway, just wait until it's time to wire it up and then use standard FC CAS and coil packs.

Mushiki

Thanks guys!

I'll read more into the DLIDFIS and probably work on that for now, and get the whole CAS thingy when I finally get a standalone.

I love this forum

arghx

iTrader: (3)

I've never even seen a thermal reactor in real life. That's some real old school stuff. The butterfly valve design for the 6 ports would have saved a lot of headaches for me though.

Mazda made the best move with the Rx-8 though. Eliminating overlap meant that the engine could idle at a stoichiometric ratio and the airpump was only needed during warmup.

Hypertek

iTrader: (3)

why? reminds me of all those tards who convert to carb

Mushiki

Why what?

My FC came with a distributor, I wanted to convert to a fully electronic, standard FC ignition system.

Hypertek

iTrader: (3)

well fit s5 parts on it

Mushiki

Read the whole thread, you'll notice it's pretty complicated, and in the long run, not completely worth it

j9fd3s

iTrader: (3)

the (nuclear) reactor is great though it WORKS. kind of like you and aaron, i hadn't really dealt with or even seen these things much.

until i bought a 79 rx7. i tuned it up, warmed it up and drove over to the smog guy. i had him pretest it, and it was just as clean as any of the catalyst cars. he turned it off, did the visual, started it back up, to do the actual test, and it almost failed...

it turns out that when they say THERMAL reactor they mean it!

however the car is now 32 years, and 103,000miles old, and not only has the reactor never been off, but it just flies thru CA smog. the catalyst cars don't run any cleaner, and the cats are lighter, but not as durable...

i have had a reactor off once, the 12A one must be near 100lbs....

Aaron Cake

iTrader: (1)

That's the only problem with the thermal reactor: it weighs a damn tonne. I have had two rotary cars with thermal reactors: my beater '78 1st gen (which has been long since scrapped) and my '76 Cosmo. The 1st gen had the complete system in place and still operating fine. When I looked under the car the first time I saw so many pipes that I had to look it up, and found a great explanation of how it works in the 1st gen FSM. I still have the thermal reactor manifold from that car in my shed, complete with the little exhaust port inserts that direct flow to the front of the manifold. It's hilarious seeing that manifold now because the outlet that connects to the rest of the system is maybe 1.5". No wonder putting a header on those early 12As freed up so much power! Lifting the manifold is decidedly a two-handed activity. It is an impressive casting.

The system in my '76 Cosmo was not complete. It was missing much of the outer shield from the main downpipe. But it still had the air pipe that ran all the way back to the rear of the car, beside the REAPS (Rotary Engine Anti-Pollution) muffler. Doesn't matter since the Cosmo is getting an EFI 6 port turbo 13B with a cat.

The thermal reactor exhaust actually generated so much heat that it had a complete sheet-metal cooling jacket fed via the air pump. This extended to approximately midway down the car. The manifold itself will glow orange in operation. Cold start emissions are pretty high with this system, but once warmed up it is very clean.