Zac's rotary redux project, because he has too much spare time.

[ProZac]

More waiting, more restoring parts that don't actually help the thing run....

A front wiper motor popped up for sale cheap, so I nabbed it. I'd done the rear motor, so figured I should do the front too.

In the scheme of things, not terrible, but stuffed powder coat, a bit of rust setting in, and filthy. Atleast it actually ran at a decent speed though, so better than the rear one! Blew it apart, cleaned everything up, sanded the commutator and gave the brushes a tickle up, they have heaps of life left yet. Didn't go full-bore on this and get everything re-zinc plated, most of the bits were absolutely fine, just needed a good clean, aluminium housing blasted, and the motor casing painted.

Reassembly time. Nothing complicated here.

I was a little bit of an idiot and didnt mark the alignment of the pivot arm when I disassembled it. I'll be able to sort that when fitting it to the car though. Draws a little less current and sounds smoother than it did before the job, so that's got to be a score :-).

Spent a few evenings sanding down, then back up through the grades, and polishing all the exterior lights. The fogs are ones I stripped and had the housings powdercoated when I had the white car, were still sitting in a box in the garage, so that's a score. Really early cars like mine have yellow lenses inside the fogs, but I prefer the clear ones, so was nice to have this set from a later model car. The yellow ones are still on my car, so maybe they'll get a resto at some point too, nice to have options :-). Everything has new LED bulbs. I'll need to put a load resistor in parallel in the indicator circuit somewhere to trick the flasher / body ecu thingee, but that should be all the lighting sorted and ready to fit.

I've got a few balls up in the air restoring other parts, the door handles are an interesting one, waiting for them to come back from powdercoat. I'm also modding a set of aftermarket headlights to bring them into the 21st century, but I'm not a hundy on how that's going to work out, will be interesting.

One day soon I'll stop procrastinating and dive into the engine bay again.

[ProZac]

I FIXED SOMETHING THE CAR ACTUALLY NEEDS TO BE DRIVABLE!

Okay, but its also an OCD wank-fest... Sooooo best of both worlds?

The stopper that actuates the brake light switch on the pedals was missing, as it had crumbled into oblivion, this is really common apparently. I ordered a new one as they're only a few bucks, expecting to just chuck it in and call it job done. While I was under there, I checked the brake light switch itself though, and found it to be faulty too. These switches have two circuits in them, one normally open, one normally closed (although this terminology becomes confusing when you start thinking about the position of the brake pedal, as it actually releases the switch when the pedal is pressed...). The normally open circuit (smaller terminals), wasn't working. It occasionally closed its contacts if you pushed the plunger really hard, and squinted just right... But not reliably. I have no idea what this circuit is actually for in the car, but there are wires going to it, so I figure I should make it work. About this time a set of pedals popped up on FB marketplace local that were pretty cheap, so I thought, why not? Went and grabbed em. They had a good stopper for the brake light switch, and a good brake light switch itself, so I swapped them into the car, and hey presto, all fixed :-).

Job done, right?

Yeah, nah.

The pedals are a really cool feature of these cars, as they're aluminium from the factory, which is a little uncommon. I now had a spare set of ragged, run down pedals, and, well, you know how much I love overboard restoring things....

First up was the stuffed switch. Getting it apart was pretty easy, just a couple of crimped tabs. Gave everything a really good clean, and sanded the contacts with 400 grit. Re-lubed with dielectric grease, assembled, and presto, all working perfectly again :-).

The pedal bodies are bare-metal from factory, as they aren't really exposed to the elements. Still, they looked pretty grunge. I blasted everything, and had the bodies powder coated satin black. The pedals themselves are just awesome, I love the stiffener bracket in there, and the pedal faces just being raw, no rubber covers. Very sports car, much wow.

That pedal isn't painted, that's just the vaporblasted finish, and it looks fookin lovely :-). I sent another batch of stuff through Christchurch Metal Refinishers for zinc and gold passivation, they're just bloody awesome guys in there. All the hardware for these was included in that lot. The springs in particular came out looking very very pretty :-).

Assembly was the reverse of disassembly. I lubed with red rubber grease as I know it'll play nicely with the plastic bushings. Nothing complicated here, but a damn satisfying result. Obviously I did the clutch pedal as well, as they need to match!

More parts to squirrel away in the wardrobe for the future when the car one day gets a major tear-down and rebuild, or when I finally admit to myself that is what I'm already doing....

 

[ProZac]

Back to regularly scheduled programming, which is of course restoring things that aren't really necessary right now... But its about the journey right? Or some shit like that... What it is, is delightfully fun :-). If you're not interested in a stupid level of detail about FD3S door handles... uhhhh, you might want to look away.

A pair of doorhandles appeared on FB marketplace pretty cheap, because they were really really rough... But they were complete :-). One of mine is missing the plastic trim insert that goes between the lock barrel and the main handle casting, which while not impeding the function, looks hella rough. It's on the drivers side too, so not even like I can ignore it as that's my side of the car! Although I'm not sure for how long, as my four year old (going on fourteen) has informed me that she wants to do a burnout in her red car... Not sure where she is learning these things, but it certainly bought a tear to the eye ;-).

The door handles on these are notorious for snapping, as while the main body is cast aluminium, the handle itself is plastic, and after years of stressing and temp cycles... one day, snaparoo. Both of the ones on the car are okay, but the rough set I purchased was snapped on the drivers side.

Did I mention they were cheap? Hah. Came with a key though, which is nice. I'll obviously swap my lock barrels into them as having different keys for the doors and ignition is a no-go. Those lock barrels will also undoubtedly get a tickly up, as a nice crisp 'snick, snick, snick' as you insert the key is one of life's pleasures... If you're a weirdo... Which I am.

Now, FD3S handles have a known problem that develops over time. As you lift the handle up, they act on a sprung pivot arm which pushes down on the control rod that actuates the door latch. Over time, things wear, and the pivot arm returns further and further, until in its returned position puts the lever point almost in line with the pivot point... This makes the first bit of movement of the handle very, very stiff, and largely contributes to the broken plastic handles, as you really need to wrench on them to open the doors.

You can see here a (completely stolen) picture of a new set of handles:

vs a totally worn out set (pic also stolen):

There is a documented mod to fix this, which on the surface seems to makes sense, and that is to carefully drill and tap the lever arm and install a small fastener that stops it returning too far. I went ahead and did this, and it 'sort of' fixes the problem, but its more of a band-aid, and doesn't really address the root cause.

With the handles assembled, and everything held in place like it should be, I scribed a line on the pivot arm in the 'most returned' position it should sit in. Then I offset from this the radius of the head of an m4 cap screw, punched, drilled and tapped:

Voila, problem solved, right!? Yes, but also no. As the pivot return spring now returns the pivot onto this installed stop, it no longer returns the handle onto its intended stop, which is this small push in rubber grommet that sits underneath the handle itself.

So what the newly installed stop ends up doing is ensuring that the pivot doesn't over-return, but that the handle is no longer pulled down tight onto this stop. This means the handle, and attached pivot have an amount of free-play, so they rattle terribly. Can't have that. I think the over all root cause of the initial problem is this small rubber stop wearing out. This is compounded by a small amount of wear in the pivot arm linkages also. Both of these problems we can fix however :-). The following fixed should work with the original plastic handles too, but because one of mine was already broken, I bought a pair of the replacement cast aluminium ones. They look basically identical though.

I drilled and tapped (M4) the small hole the push in rubber stopped goes into, and then modified some M4 rubber equipment feet, shortening them down to ~2.3mm. I figured this would give an amount of adjustability if needed, but TBH, I just put them in as tight as they would go, secured them with a nut on the back side, and they were spot on from the get-go. I've also sand, and then vapor blasted the handle bodies in these pics, that's why they look so shiny :-).

Stupid me didn't take a photo of what it looks like installed from the front, but I'm sure you can imagine. I'll have one later when they're all assembled.

The other part of this problem is that wear in the pivot arm itself. I think this is actually a pretty small contributor to the over all problem, but tuning it up a little can't hurt. I grabbed a couple of M4 washers, which were pretty terribly manufactured, resulting in different thicknesses from 0.7mm to 1.1mm... This was great though, as it meant I had options, as I was going to use one as a shim :-). Ended up on around 0.8mm being about right.

You can see it installed between the rod-clamp, with 'B' on it, and the handle itself. Depending on which side you put a shim here, it will move the handle relative to the housing, so make sure you put it on the side that results in it looking right :-). Probably different for every combination. I suspect thinner plastic shims, installed on each side would be a better option. This limits the side to side play in the pivot, and just generally tunes everything up so its a bit nicer.

With all that sorted, I fully assembled them with everything in place and damn, satisfying result! Lovely smooth action, no stiff point at the beginning of the travel, no rattle, nice and sorted. I left the over-return stop in place, the spring was returning the handles onto the new rubber stoppers, and it was only *just* touching the cap-head stop. This means that if those rubber stoppers don't live up to the task (a total possibility), the pivot will still work, but things will just start to rattle again, letting me know I need to find a better rubber stopper solution down the line... Cross that bridge if I come to it?

With the mechanicals sorted, next up is the cosmetic restoration, which has turned in a slight cluster-fuck. Choose your powdercoaters wisely my friends!

[yoeddynz]

Far out. Such detail. I'm impressed. Thanks for sharing. 

I only want an fd even more now so I can tinker away on it like this.  I think if I wrote in such detail about a k11 people would tune out quick? 

Those alloy pedals are lush! 

[ProZac]

Thanks mate :-).

If you wrote it, I'd read it :-). One concern with extreme detail, is a lack of timely progress.... But as long as you're loving the journey, learning, and sharing, that's way more important.

.

.

.

Can't wait to rip a mean skid in it though ;-).

[Roman]

I love reading detailed stuff like this, really makes me feel like ive achieved something for the day when I obviously havent. 

Keep it up please

[ProZac]

Bloody hell, the saga of these door handles! Definitely could have just bought a new set... I've saved a bit of money this way, but invested a heap of time in its place... Still, every part has a story, its something you touch every time you use the car, and this set is even better than a new set now with the aluminium cast handles instead of the factory plastic pieces.

I got a local company to powdercoat the handles, and they did a pretty average job TBH. They said they'd re-coat them, but after waiting a month without that happening, I gave up and just collected them. The coat was so thick in places I couldn't assemble them without cutting bits of it away, and the finish was pretty rubbish... I re-blasted them to get it all off and was back to where I started. After watching a couple of youtube videos (to become an expert in the subject, as we all know that's what youtube is for...) I purchased Eastwoods DIY powercoating setup and some semi-gloss black powder.

Wow, this is one of those rare occasions where the reality was actually as easy as it looked on youtube, and the outcome surpassed what I was expecting. Easy process, nice and clean, and super durable finish in exactly the right colour / gloss level to match the factory parts.

Handles there ready for final assembly, with some other bits I've got on the boil.

I made some better rubber stoppers to set the handle height correctly when the doors are closed. These are 16mm diameter m4 threaded rubber equipment feet that I trimmed down, chucked up in a drill and linished to about 2mm thick, while spinning them in the drill to keep things even. Time will tell if they're up to the task, but this thing will never be a daily again, so I think they'll be okay.

Then assembly is simply the reverse of disassembly, with the addition of an m4 flat washer as a shim.

Just to the right of the 'B' clamp there. Kind of a pain to get into place, but it removes all the play in the system.

All the moving parts got a smear of grease so keep things smooth. You can see the stopper bolts there, but they're not engaged when the handles are fully closed, so are doing nothing whatsoever.

With the larger diameter stoppers, the handles close down onto them properly. The original ones seem to small to really do much. One of them was missing on this handle set, and the other was pretty thin.

Voila! What a faff for a set of door handles.... But dayum, they do look fine :-). I've blasted all the lock housings, but I need to take the tumblers from the original set so the car is keyed the same all around. Future job, these can get wrapped up and put away in the wardrobe for now. Back onto things the car actually need to run... maybe... I'll probably get distracted by something shiny ;-).

[Dell'orto]

I do love how much effort you put into a door handle! I'm expecting similar amounts of OCD in the engine itself too thanks

[ProZac]

1 hour ago, Dell'orto said:

I do love how much effort you put into a door handle! I'm expecting similar amounts of OCD in the engine itself too thanks

The motor has good compression, so it'll remain un-opened till tis running and I likely find out it leaks water, hah. The surrounding systems, turbos, alternator, manifolds etc will be receiving attention for sure however :-).

[ProZac]

Okay, okay okay. These door handles. We're so far past the point of ricidulousness with them... But they are finally done! Well, almost...

Early FD's, or maybe if they were optioned with it, I'm not sure on the determining factor, have a light in the drivers side keyhole that illuminates for 30 secs when you lift the handle with the door locked. Presumably this is so you can find the keyhole in the dark easily. My car has the wiring there for this, which means it must have had this at some stage. The light is long gone, and the door handle has been replaced at some stage... But, if it was there originally, I've got to make it work again, right... right? RIGHT!?

I CAD'd and 3d printed up a wee housing for a wide angle high brightness white LED. It has a forward drop of 3.1V at its rated 20mA, so I put a ~470Ohm resistor in series with it to keep it happy at automotive voltages. Shrunk some shrink onto it to seal it up, and potted it into the housing. Should hopefully last a while :-).

This is where it sits, it's held in place by the spring slip that keeps the key-barrel where it needs to be.

I got a pair of replacement frosted plastic keyhole spring covers from a guy over in the states.

Off vs on:

These door handles have to be the most thoroughly 'touched' set in existence by this stage, and I know they're just handles, but fuck they're lovely to use. Smooth, super positive stops at the end of the travel... I've disassembled, blasted and cleaned all the lock barrels and tumblers. Re-lubed the tumblers with a dusting of graphite powder, and the detent ball with a smear of grease. They keys now have a nice crisp insertion sound and feel... Fuck, typing this out I'm really realising how much of a barry I am... But, honestly, so much fun in a project like this.

Last part of the puzzle is to cut some foam buffer strips to replace the originals. I've got some closed cell foam here that should be good for this, or there might be some knocking around at work too I think. They're just straight strips that are glued into place on the backside of the housings, around the perimeter.

Word has it that supply of these new is drying up, so I'll hang onto the original set from the car at the moment and maybe give them the same treatment at some stage. Keep them as spares or gouge the market when new ones are truly NLA, hah.

In other news, some of the wiring harness build supplies finally showed up! Design is being fleshed out... it's setup as basically a stock replacement harness, but much better materials and fit. Plus plenty of things tidied up and added in to make running different ECUs in the car as easy as possible, and additional sensors not a pain to add down the line. I've got stock 8bit and 16bit ECUs here, a PowerFC + Datalogit, and a Link Fury. I suspect it'll run on the PowerFC for a while till I get another control system for the twins figured out and can transition over to the link. Fun (Fast) times in Tahoe.

 

[ProZac]

I'm going to technically claim that this counts as working on something the car critically needs to work, as headlights are pretty important, really. As should be pretty obvious, this thing has had a home-based re-spray at some point, and the person doing the job was not exactly clinical with their masking, so its dusty red and dirty clear overspray just.... everywhere. Including all over the headlights. I've sanded and polished a few lights in my time (including every other exterior light for this car...), so was anticipating a relatively smooth, if somewhat tedious job...

Instead, I veered hard left (well, actually, I made that turn a long time ago, so I just stayed on the road I'm already on...) and decided to do a projector retrofit. I don't really have any defensible reason for this, other than I think they look cool :-)... Well, and I remember the headlights in my last FD being just terrible, even with replacement higher wattage bulbs. There are a couple of places that sell these ready made for FD's, but I'd be looking at around $1500 kiwi, and that's not money I'm willing to part with for something I can do myself (this is always flawless logic...).

After researching a bit on the topic, It looks like the way to go is to use a pair of the available aftermarket headlight housings that shift the beam pattern generation onto the housing itself, and use a totally clear lense. There are a few places selling these, but they're all the same SONAR housing. I found a pair for sale cheap on ebay, so was around $180NZD into things.

Getting them apart suuuuuuuuucked. Well, that's not strictly true, it wasn't particularly hard. Remove the spring clips, heat liberally with a heatgun, and pry slowly and gently... what sucked was dealing with the adhesive after the fact. This shit is sticky, and gets everywhere. It is reusable however, so if you can get them apart cleanly, you'd be able to re-heat the glue, reassemble and have them nicely sealed again... This is not what I did because.... reasons. Instead I decided to clean off all the glue, and will re-seal them myself using some butyl tape... I regret this decision. Prying all the old adhesive out with a screw driver took ages, and removed a lot of the chrome finish. Petrol was pretty decent at dissolving the residue left behind. I managed to slip with the screw driver and scratch one of the housings on the inside pretty decently. Guess I'm painting them then!

The lenses are polycarbonate (I'm pretty sure, anyway), and solvents will mark them. The best way I found to get the glue off these was to freeze it. It would then chip off pretty cleanly, and the residue could be removed with some citrus goo-gone type stuff.

Dispose of this shit while it is still frozen, because once it warms back up to room temperature, its fucking annoying to deal with.

With the housings apart and cleaned, I started measuring things up, and settled on some 2.5" bi-LED projector units. These set me back around $80, and a two month wait. Lots of sellers of these on aliexpress, but they all look like they're made in the same factory: https://www.aliexpress.com/item/1005002797444025.html?spm=a2g0o.productlist.0.0.177c7147zgorov&algo_pvid=9558ac48-7b09-434a-802a-155a9e69b03d&algo_exp_id=9558ac48-7b09-434a-802a-155a9e69b03d-4&pdp_ext_f={"sku_id"%3A"12000022229395886"}

If you're ordering any, make sure you get them with the correct beam pattern for the side of the road you drive on. Left in this case of course :-).

From the measurements, I figured they'd fit inside with a few mm of clearance to the front lense. They come with an adaptor to mount where an H4 bulb originally went, so that's a score. Once they arrived I mocked them up, and immediately found that the adaptor mounts put the projects at totally the wrong angle, and the beam pattern was rotated along the axis of the car by around 20 deg. I 3dprinted some other adaptors and for them nice and level, and things were starting to look good. 3d printed adaptors aren't going to cut the mustard though, as they'd soften and melt with the heat of the projectors. Luckily we got a little waterjet cutter at work a while back, and its just bloody perfect for stuff like this :-).

Cool. Now the rotation of the beam pattern was correct, I gave aiming them a go, and discovered that to get them level I was running out of adjustment on the bottom adjuster. Cue some more 3d-printing to make another insert. This bolts on using some existing holes so everything is totally reversible down the track.

See all that dusty overspray? It's literally everywhere, that's the shit I'm dealing with.

Phew, now I had enough adjustment I could get everything squared up. As I munched the housings pretty good cleaning them up and generally fucking around with them, they needed paint to look presentable again. cue some blasting to prep them...

And some gun-metal touch up paint. Side note, seems repco isnt stock these little cans anymore. Shame, its really good paint, dries in like 5 mins with a heat gun, sprays out really well, and is just excellent to work with.

It's more of a semi-gloss finish once it's dry, which looks really good in the housings.

Time for final assembly and another test-fit!

Hmmmmmm, frog eyes. I like them, but... honestly, it was a hell of a lot of work for maybe a questionable result? Hah. At least I had fun. Obviously haven't driven with them yet, but testing at night in the driveway shows a hell of a lot more light, in more distinctly correct places than the factory ones.

That being said...... I also restored the factory housings.

You know, because the projector ones are probably not even vaguely legal, and maybe these will actually work okay with some of the new-fangled LED replacement bulbs that are apparently not-shit?

 

[ProZac]

I have been working on important engine things, honest! Part of that has been getting all the gaskets sorted, making emissions block off plates, re-kitting the injectors and manifolds... etc, etc. Will tidy all that up and post about it.

Nothing like using a 6 figure bit of gear to make a $3 gasket though... Usually I just use a flat bed scanner, with a ruler in the frame as well for scale, but this wont lie flat on the scanner.

Some CAD:

And the laser cutter. I've cut all the other gaskets I need basically the same way so I don't have to nickel and dime around waiting for them to arrive. Plenty of ways to skin this cat, but I've got access to the gear, so may as well use it.

The small win project was the rear boot trim. The piece at the very back of the boot space is broken on most FD's that I've seen. They've meant to have these clip pieces to help keep them from flapping about:

(Image stolen from the nets).

Both of those were snapped off on mine, and the one two I have also...

I suspect you can see where I'm going with this.

Obviously the fasteners stick out like dogs bollocks at the moment, but I've got something in the works for refinishing all those boot plastics back to as near as OEM as they could get, and I'll powdercoat the heads of those fasteners, and the clips themselves when its all apart again.

It's..... terrifying when something works first time, but, well, hmmmm, here we are? I could cut them again, and do a better job of bending them in the brake, as opposed to bashing them in the vice with a hammer..... But really, they're fine as is.

[ProZac]

Time for a quality Christmas jigsaw!

Need to find the corner pieces... Actually I think I'd prefer they stay inside the motor ;-).

[ProZac]

Whoa, the throttle bodies on these things are a..... thing. I got the above jigsaw all back together. Turns out I'd lost one of the plastic spring bushes, and the flange on the other was cracking off, so I grabbed an off cut of acetal from work and turned up a couple of new ones. That let me get the thing reassembled. I took a heap of photos of how everything came apart, so getting it back together wasn't too much of an issue. Kinda fiddly in spots, but follow your nose and it goes back together reasonably easily. The throttle shaft seals still seemed pliable and plump, so I didn't replace them... Time will tell if that comes around to bite me in the ass. Ideally I'd like to go with some sort of e-throttle setup in the future.

There wasn't actually a complete throttle body with the car when I got it, so I purchased this one secondhand, and it was pretty filthy:

But, it was complete, and moved smoothly :-). After stripping, blasting everything (lots of careful masking involved), kind of a pain in the ass....

Much better.

But holy crap, there are a lot of adjustments on these things! There are threads all over the internets of people having problems setting these up, so I thought I'd better develop a plan to follow. Not saying the plan is a 100% way to go, but I need something to follow so I can go through a process and collect data, and iterate from there. Going to write this plan out here so I can refer back to it later when I've forgotten all this again.

The first screw I've set is screw A. This is the stop that the single butterfly stops against. This single butterfly feeds the primary intake ports. As it's in the name, these port are the primary ones, so they're used all the time, along with the primary injectors always delivering fuel. My initial setting for this is that the primary butterfly stops against this when it is fully closed. After aligning the throttle blade, and thread locking the screws in place, I let the throttle close as far as it can against the housing. I then advanced this screw till it was just in contact, then about 1/10th of a turn more. This should mean the throttle blade is never eating the throttle body housing, but closes as much as possible.

Screws B and C adjust the cold start warmup system. You can see the two black pipes in this picture. Coolant flows through these, which warms up and extends the wax pellet push-rod screw B is pushing against. Unfortunately they're a little corroded on the outside, but there is still heaps of metal there. Will always run anticorrosive coolant in this, so should progress any further. This wax pellet rod extends as the coolant gets hotter, and retracts as when things cool down. This screw is threaded into a cammed bracket, which has three marks on the cam (one of them is obscured by the red oval I've drawn, but its there). The FSM has specs for the relative positions of the roller on the bracket screw C threads into (we'll get to this one in a minute) and the cam at different temperatures. The upper most (in my picture) mark should be central on the roller at -20degC, the next one down at 0degC, the next one down at 25degC, and finally off the lower edge of the cam at 60 degC. It's pretty hot in my office today, so I've adjusted screw B such that the roller is lined up with the third mark.

Screw C adjusts how much effect this cam actually has on the throttle blade position. As you screw this in more and more, it opens the throttle blade more and more, as long as the roller is contacting the cam. I suspect the final setting for this will be such that the roller separates from the cam just as it is passing over the lower edge, with without a sudden jump in its movement. Currently, I've set it so the roller is only *just* touching the cam at this 25degC position, for reasons that will hopefully become clear :-).

Cold start systems are important, but they're only ever going to work properly if the base idle speed with the engine at normal operating temp is setup correctly. The throttle obviously has adjustments for this as well.

Screw D is called the Air Adjust Screw (AAS), and screw E is called the Throttle Adjust Screw (TAS). Screw D has a tapered end on it and fits into a matched tapered orifice. This orifice is connected across either side of the primary throttle blade, so as you back the screw out, it allows more and more air to bypass the throttle blade. Screw E is the stop for the the secondary throttle blades, and sets their closed position. In practice, these screws have the same effect on the idle, in that they will let more air into the engine. There is a slight difference though, as at idle the ECU wont be using the secondary injectors, so adjusting the idle with screw E will let more air into the engine via the secondary ports, but this wont have any fuel injected with it. This wont be an issue though, as at idle things are happening very slowly, and there is heaps of time for the charge to mix in the combustion chamber as it whizzes around to the other side of the motor to make brap brap noises. Reading the FSM, what I can parse out is that you use screw E to broadly set the normal operating temp idle speed, and then screw D to fine tune it.

I've set screw E in the same way I set screw A, such that the secondary throttle blades fully close to within a bee's dick of the throttle body housing. I've wound screw D all the way in, so there should be no air bypassing the primary throttle.

The last adjustment is the damper dashpot, F. This is a damper the throttle closes against. It's hard to push in, but extends with no effort. Lots of bump damping, no rebound damping. This needs to be set with the motor at normal operating temp, and such that the throttle breaks contact with the plunger at an engine speed of 2600 - 3000 rpm. Obviously this will need the engine running properly at N.O.T. To setup, so I've wound it out so it doesn't contact the throttle at all.

Reading through that, there might seem like some odd decisions, as I've essentially set the throttle up in such a way to ensure the thing isn't going to idle. It's going to have almost no air bypassing the throttle, will starve and die. This is for a reason however, and comes back to how I like to tune a setup. First thing is to get the engine firing and running, probably with some throttle manually applied. Then I can get it up to temperature, check for leaks, fires, all those things. With the engine up to temp I can use screws D and E to set the normal operating temp idle. It's really important this is done without the cold start system having any effect whatsoever, as if it is, when you go to set the cold start up, your normal idle setting will also be effected, and you'll end up chasing your tail.

Now, the FD also has an ECU control idle air solenoid which can allow varying amounts of air to bypass the throttle, but for all this initial mechanical setup, I'll keep this unplugged to eliminate it. AFAIK the ECU only uses it to idle up the motor when the A/C, power steering, or alternator are loading things up.

There is also the TPS to think about. The FD TPS is a little odd in that it has two analogue output channels, narrow range and full range. Talking to Ray (arghx), it sounds like this is a throwback to the FC3S days, and probably something to do with Mazda re-using existing code in the FD ECUs. Total speculation, but having been an engineer on a few evolving projects, this is totally something that would happen. The FSM has specs on setting this up. With the throttle closed, adjust it so the narrow-range signal is between 0.75V and 1.25V, and the full range signal is between 0.1V - 0.7V. I powered up the TPS from my bench supply and set it thusly.

Strats:

• Stock ECU initially, to get things running, proof the rest of the system, and ensure it doesn't burst into flames. It's a 'known quantity' as such.
• Make the thing run, will need the throttle manually opened to keep running.
• Get it up to normal operating temp
• Make sure everything is functioning like it should. No error codes from the ECU, so no limp modes or anything (exception to this is the idle control solenoid, but I can trick the ECU into thinking this is fine with a resistor in its place).
• Adjust the warm idle speed to just below target (~750RPM) with screw E
• Adjust the warm idle speed to the final target with screw D.
• Adjust dashpot F so the the throttle breaks away from the plunger at an engine speed of 2600RPM.
• Turn the thing off, go inside and have many whiskies.

 

• Recover from hangover. Remember: You're old now, this might take a couple of days.
• With the thing dead stone cold, try to start it with no throttle applied. Expectation is that it will not start.
• Advance screw C 1 turn, try again. Repeat this procedure till the engine starts with no manual throttle opening. Idle speed should be higher than warm idle target.
• Allow the engine to warm up, idle should reduce gradually as it does and the wax pellet rod extends.

 

• Iterate from here. The only screw that should need adjusting at this point is screw C.

 

Hopefully I can pull that off.

 

In other news, most of the supplies needed to build the EM (main engine) harness have shown up! Huzzah! I'm going full ham-spec on this. The car doesn't need it at all... But I've built lots of high-tier harnesses before for other people, and I really want something totally schmick for my own car for once. M22759/32 throughout, twisted, DR25 sheathed, booted, sealed.. All the good things. As much as can be with using OEM automotive connectors also. I've designed it with lots of extras in mind down the road, as I don't want to have to build another one for this car, ever. When I want to change out the ECU for something other than the stock one or a power FC I can just make adaptor harnesses at the ECU end, nice and easy. Just got through the design process for the layering, built a test section for the main core to make sure it was going to lay up nice, looks lovely :-).

Progress is progress?