Sprocket's Competition

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Originally Posted by j2k4

This car is good fun.

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I'm happy for you, Kev.
Hope it all pans out the way you plan.

I probably won't see the Beast for two weeks- Sigfrid's wifes birthday is next weekend and I suspect flogging on the car isn't part of the festivities- so I'm gearing up for the (hopefully) last big project...the dash.

Given the sorry state of the rest of the car, we're assuming that the wiring behind the dash is shoddy as well, so the whole thing is coming out for an inspection.
The heater is not working and we hope to fix that along with cleaning all the ductwork.
Once the dash is back in we can install the new stock gauge panel and a stereo (amazingly, the car is quiet enough that a stereo makes sense now).

This will probably take place at my house so I can work during the week while Sigfrid is earning the big bucks.

During this time I have three sub-projects to work on as well, two of which will be considerably simpler with the dash removed.

-I think the clutch system would benefit from a larger (specifically, a 1" size) master cylinder. With the current 7/8" cylinder, full pedal stroke is required to move the slave far enough to cleanly disengage the clutch.
I've had to remove all freeplay from the system to achieve this, which is not a good thing. A larger master will push more fluid for the same pedal stroke and should allow for a wider range of adjustment.
I'd like to find a Japanese OEM part for this and dispense with the crude adaptor used to mount the Wilwood master we now have.

-I want to install the 929 brake booster/master cylinder/proportioning valve and see if the brake feel doesn't improve.

Both of these hydraulic jobs will be much simpler with the dash removed since I won't have to contort into the footwell to access the mounting bolts.

- Finally, I'd like to fabricate a real cold air intake.
We've already paved the way for this by relocating the radiator and making the trim panel for the rad.

The problem here is the MAF unit...it's big and bulky, making the packaging quite difficult. Hood clearance is quite an issue in this area.

Accordingly, I've been researching tuning options that would remove the MAF.
It's called "speed density" tuning and while not as sophisticated as MAF tuning, the real world performance is reputed to be nearly as good.
This is a totally unfamiliar area for me, I'm hoping our tuner can steer us in the right direction.
If the MAF must stay, I'll have to completely rethink my options.

After this final round of flogging, she should be capable of daily use and we can begin some fun stuff...have I mentioned there's a body kit in Sigfrid's attic, waiting to be installed?

All worthwhile refinements.

A body kit, you say.

Huh...nice?

Quote:

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Originally Posted by j2k4

A body kit, you say.

Huh...nice?

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Hard to tell.

It's already been painted- Mazda Montego blue- so it doesn't match our car.
We've had the nose mounted once already and the lip is very low, so we scraped a lot going into driveways etc.
Since we've gone back to the higher stock springs, this may no longer be an issue.

The sideskirts look OK, haven't even test fitted them yet.

The rear valance cannot be tried until we cut off the tow reciever- yeah, this thing apparently once towed some sort of trailer (??!!)- which is on the list to do...sometime.

Personally, the body kit is way down on my list of important things to do, Sigfrid may feel differently.

Car goes to the tuner on Wednesday and will be done on Friday.
I'm very curious what this will do for us.
I have zero background in American motors, so I can't tell if we're running well now or not.

Sigfrid has started to daily drive the car- to date, I've put about 5 times more miles on the car than he has- and he sent me a list of things he doesn't like.
I'm actually encouraged as most of his complaints have nothing to do with the swap and are little niggling issues that anyone might have with a totally stock used car.
If our biggest problem is now the speed of the power windows, I think we've crossed a Rubicon.

This is a good thing.

As to the tune, while I would expect any power gains to be fairly significant, they won't be on the order of what one would expect from a turbo- or super-charged set-up, but certainly more than, say, a re-curve of the distributor...maybe 60-80 hp, maybe more - that's a bit of a blind stab on my part, but if you're running reasonably well right now, I'd think you're in the ballpark.

I can't wait to hear what the numbers actually are.

I'll tell you, some of the stuff I'm finding out with these turbo-cars...stock-block (over 100K mile specimens) cars with minor injector/fuel-pump upgrades, piggyback ECU controls, larger turbos and a good dyno-tune (by a tuner familiar with the platform, natch) are routinely yielding 600-700 AWHP - phenomenal numbers.

The record holder is a fellow named Matt Monett, who runs in the eights at over 165 mph-

http://www.youtube.com/watch?v=bqRpJeMvM08

-but there are scads of guys running low tens.

Hell, I'm only looking to run mid-to-high-elevens...probably do it for about 7K.

BTW-

Check out the size of the snails on this thing...can't figure out what it is, 'cuz the video is so damn dark, but there's no mistaking that serious shit is going on...

http://www.youtube.com/watch?v=vQ8pU...layer_embedded

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Originally Posted by j2k4

BTW-

Check out the size of the snails on this thing...can't figure out what it is, 'cuz the video is so damn dark, but there's no mistaking that serious shit is going on...

http://www.youtube.com/watch?v=vQ8pU...layer_embedded

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From the comments below- and the relatively low redline- I think it's something American.
But Jeebus on a pogostick, those turbos could suck a small child right out of a stroller.

As for our tune...
I'm very curious to see what happens.
I've not met the guy in person- and not likely to- so I sent along a few questions for Sigfrid to ask.

His response was not good...something along the lines of "If your friend knows so much about it, why doesn't HE tune it?"

I had prefaced the remarks- and have stated here- that this is way out of my experience zone, so I didn't think I would be stepping on anyone's toes but he apparently brooks no inquiry...he's gonna do what he's gonna do.

I'm sure the car will run better and just smoothing it out (she runs like crap till warmed up now) will be a major improvement, even if the power level stays the same.
She is after all, a street car and driveability trumps absolute speed.

I'll know on Friday...

Well I never saw anything wrong with questions, I mean hell you're only asking right? The guy sounds like a dick. Best line in this whole thread BTW

"Jeebus on a pogostick, those turbos could suck a small child right out of a stroller."
I really laughed out loud

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Originally Posted by clocker

Quote:

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Originally Posted by j2k4

BTW-

Check out the size of the snails on this thing...can't figure out what it is, 'cuz the video is so damn dark, but there's no mistaking that serious shit is going on...

http://www.youtube.com/watch?v=vQ8pU...layer_embedded

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From the comments below- and the relatively low redline- I think it's something American.
But Jeebus on a pogostick, those turbos could suck a small child right out of a stroller.

As for our tune...
I'm very curious to see what happens.
I've not met the guy in person- and not likely to- so I sent along a few questions for Sigfrid to ask.

His response was not good...something along the lines of "If your friend knows so much about it, why doesn't HE tune it?"

I had prefaced the remarks- and have stated here- that this is way out of my experience zone, so I didn't think I would be stepping on anyone's toes but he apparently brooks no inquiry...he's gonna do what he's gonna do.

I'm sure the car will run better and just smoothing it out (she runs like crap till warmed up now) will be a major improvement, even if the power level stays the same.
She is after all, a street car and driveability trumps absolute speed.

I'll know on Friday...

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Well, tuners tend to be pricks...they don't want to impart knowledge to anyone, and I suspect your questions were probably a bit too on-point.

Suffice it to say (in my case, anyway), a good guess is still naught but a guess, but hell, he probably gets all sweaty when someone else wins the fucking Lotto, so.

The tuner just dropped the car off at Sigfrid's.
Apparently, she runs quite well, despite the fact that we have a few issues to sort out.

One O2 sensor is dead, we'll just replace them both with new.

The Holley 58mm throttle body is too large for our setup and the ECU cannot set a steady idle, so I'll put our stocker back together and we should be fine.

Our crankcase venting is not right, there is excess pressure- probably the cause of our oil leaks. He's going to send us diagrams of the factory layout and we can adjust accordingly.

The fuel tank is not vented/recovered properly.
Everything is right in the engine bay, so the problem is back at the tank...oh joy.

Sigfrid has gone for a short test ride and says she's a whole new animal, acceleration is markedly improved, she'll pull to 6K RPM, no vibration and idle is (slightly unsteady) at 600 RPM.
We had one bad fuel injector clip, the injector worked but not as it should...the tuner replaced it and all is well.

So, with the exception of the fuel tank venting, we can fix all the problems in about an hour and have a fairly decent runner.
We found a Corvette intake snorkel- it's on it's way- so I can begin to finalize our cold air intake.

The light at the end of the tunnel is beginning to blind me.

All hail the tuner.

I wonder how much power you picked up?

I wonder as well, too bad dyno time is so expensive.
I'd be happy with 300 at the wheels, Sigfrid probably would not.

I'll be getting an update later after he drives to work.

I doubt my bosses' Bullitt would be cool enough for him, but it's for sale - 475 RWHP, and pretty mildly tuned, to boot - 36K.

Lemme find the link...here you go...

http://www.autotrader.com/fyc/vdp.js...standard=false

Thanks, Kev.
I'm going over there this afternoon for a while and I'll mention that.
And threaten to kill him if he even considers it.

Somehow Sigfrid managed to eke out a couple of work hours during his wife's birthday weekend.
Not sure how, not gonna ask.

We're going to address as many of the issues raised by the tuner as possible.
I have the stock throttle body cleaned up and ready to install.
We have new O2 sensors and PCV valves.
Not sure what else...

I should get a chance to drive her and see what the tuner hath wrought.

Again, 'bated breath, etc.

Well, yesterday's work session has come and gone and I'm somewhat underwhelmed by our results.

Installed the new O2 sensors (15 minutes...most of which was undoing the electrical connectors designed by Satan) and the stock throttle body.

The "Check Engine" light (or, more properly, the "Malfunction Indicator Lamp"/MIL) now stays off, so the ECU is apparently happy with the O2 sensors.

As far as I can tell, swapping the throttle bodies did nothing for our irregular/hunting idle issue.
A common cause for this is leaks through the throttle shaft seals but after an inspection of the area, I'm not willing to get into those...made no sense to me and I'm afraid I'll screw it up.

We might have a bad TPS (throttle position sensor) or Idle Assist solenoid but I'd have thought the tuner would catch that.

The car will now rev freely past 4k RPM (not easy to do in a residential neighborhood, BTW) but still vibrates too much.
We think the culprit might be the main crank pulley/harmonic balancer which is the unit from our first 383 stroker motor.
I wish I knew more about these engines because we seem to be chasing down issues mostly related to our bastard build motor and neither Sigfrid nor I are very savvy about how much mix/matching is allowable with these things.

At any rate, this week I'm going to attempt harvesting the balancer/pulley from the same junkyard donor that gave up our new intake manifold.
If I can get it- and that's a fairly emphatic "if"- we'll try it out and see what happens.
After that, I'm out of ideas and we'll need to buy some expert help.

Despite the above quibbles the car does seem to run better.
She averaged 18 MPG last tank but there was the tuning session and lots of acceleration "testing" during that time.
This next week of daily driving should give us a more accurate indication of the mileage to expect.

As darkness fell and the temperature dropped, we retired to the patio and imbibed adult stimulants and talked.
We are both very pleased with the dramatic improvements since the motor was properly mounted a few months ago...she actually started to behave like a normal car.

However, the gap between a "normal" car and a "great" car has never been more apparent and after all this work and money, we want a great car.
We are probably about $10K away from achieving this level- and that does not include any bodywork or paint.

Sitting in the driveway is Sigfrid's 2009 RX-8, the best handling car Sigfrid has ever driven (and he has more experience than most).
It's in perfect and unmolested condition.

There is a kit available to mount an LSx series V-8 into it.

It is so very tempting.

Sell off the Beast- almost certainly at a substantial loss, which, emotionally at least could be written off as a "learning experience"- buy a new crate engine and graft it into the Mazda.
There are significant but Byzantine subplots to this plan which I'll not go into but the fact is, we both are tired of fixing things on the Beast that have nothing to do with the swap and should never have been touched in the first place. The carnage seems endless.
The latest example of this is the door sill switches. Every car has 'em, they're the little plunger type things that the door depresses when closed - they're what operate the courtesy lights and are also tied into the security system.
Ours were not removed- which involves one Phillips screw- oh no...ours were gutted and left in place.
The wire for it was cut back to the main harness in the sill.
I cannot imagine a rational explanation for doing this.

We've bandied this idea about for a few months and it's becoming increasingly logical and attractive.
I'm on board.

I would lay odds the vibe problem is your balancer/damper - the 383 is a crank/block swap and requires different balancing than the stocker.

If I recall correctly, it's a combination of 350/400 CID parts; one is internally balanced, the other externally.

Get one for the engine/displacement you are using, pronto.

Wilco.

Also-

IIRC, the 350 crank was used in the 400 block to make a 383, and - though I think it would be a massive stretch - the 400 flywheel was peculiar to the 400 (because of the balance issue), make sure you don't have one of those, fucking things up...I assume/hope you have a removable bell-housing cover.

This is unlikely, as you said the 383 was pro-built, I think, but.

The flywheel came with our new engine, so I assume it's correct.
The front crank hub/pulley are remnants of the 383 and I have no idea whether they are suitable or not.

Everything about the car was represented as "pro built" and we've seen how that turned out.
Maybe they meant "professional accountants" or "professional hit men" and Sigfrid just assumed professional mechanics had been involved.
An easy mistake to make, I'm sure you agree.

Well, he's a great guy, but, hey...he's young and impressionable.

I snagged the front pulley/balancer off the junkyard donor car yesterday...not an easy task with hand tools and no puller.
There was blood.

After that was accomplished, I did my usual stroll to see what might be new.
Spotted a Subaru WRX with the engine pulled but an intact brake setup (sadly, no calipers).
A bit of backstory...
This car comes with the largest bore master cylinder I've seen on a junkyard car, 1 1/16" bore. I pulled one of these last year (just the master cylinder) when I first began my brake experiments, loved the pedal feel, hated the performance. Tried it again a few months later with a different booster but got similar- unsatisfying- results.

This MC confused me because it contradicted my expectations so dramatically.
I finally decided that I'd have to try it again but only if I could use the whole original setup, which meant I needed the booster unit.

Removing the booster from the Subaru is a daunting task, it almost seems that the chassis was built around it.
I'd hate to be the Subie line mechanic tasked with replacing a booster in a completely assembled car...I had the double advantage of an empty engine bay and complete disregard for anything else in my way and it still took nearly two hours to lever the booster out of the car without damaging it.
Absolutely nuts.

At the time I was thinking of trying this in the Beast but given her uncertain future, I'm going to put it in my car.
If it works out, good for me, if not, no harm no foul.
Besides, I haven't done anything nice for my baby lately as I've focused all my attention on Sigfrid's project.

Time to play in my own sandbox for a while.

I heard that.

What do you drive bud?

You've asked that before.

Because of the upcoming Mother's Day weekend, Sigfrid opted to take Friday off to work on the car.
A lot fewer interruptions with no family units around.

We had two major projects lined up and got them both done in good time.

The new (junkyard) harmonic balancer was installed and really helped (in fact, probably eliminated altogether) the engine vibration over 4k RPM.
Excellent.

Sigfrid has not been happy with the brake pedal feel and I agreed that it could be better.
I had recently procured the booster/MC from a Subaru and it was prepped for install into the Beast.
Here it is, cleaned, painted and configured for his brake lines...
http://img.photobucket.com/albums/v78/clocker/Red36.jpg

http://img.photobucket.com/albums/v78/clocker/Red35.jpg

And installed...
http://img.photobucket.com/albums/v78/clocker/Red39.jpg

http://img.photobucket.com/albums/v78/clocker/Red40.jpg

Brakes are now absolutely superb...best setup I've found to date, I'm off to the junkyard today in search of a similar set for my car.
I love it when a plan works out.

We also addressed a few smaller issues, the car now runs better than ever.

Assuming she survives another week of commuting- and I have every expectation she will- we will probably start on the interior next weekend.

Now that the mechanical platform is nearly complete, the diff has been exposed as the final big weakness.
It just ain't right and is the last remaining part of the original drivetrain, which automatically makes it suspect in my book.
It doesn't lock up consistently and makes weird, vaguely scary noises.
We may also have to upgrade our axles but won't know till we pull them.

So, the search has begun for a new differential, preferably one from an automatic with 3.90 gearing.
Our current 4.10 diff renders 1st gear all but useless, the 3.90 should not only help there but highway mileage should improve as well.

Replacing the diff while maintaining our alignment will require dropping the entire rear subframe as a unit...a fairly big job.
We decided to do this because it will also expose the fuel tank, which has a pretty complex system of vents/check valves/separators that we need to freshen up. All of this nonsense is situated on top of the tank is is not accessible till the tank is off the car.
It's a crappy job but needs doing.

Soon as we locate a diff, this will get slotted into the schedule.

What sort of bore size has that MC got, and I'm gonna recommend a 3.73 rear ratio; should be easy to find.

You've got the 5-speed, after all, and 1st is pretty low; you've got low weight and lots of power.

If he doesn't like the way the mill pulls that gear, then build in more power.

How many overdrive gears has that box got, anyway?

MC bore size is 1 1/16".

3.73 would be nice but Mazda only offered 4.10 and 3.90 stock, so that's what we have to choose from.

We actually have the six-speed and I believe 4th gear is 1:1, so both 5th and 6th are overdrive.

Oooh.

Brain fart.

Are those standard ratios for the RX7, or are there some automatic ratios you could swipe from another Mazda diff?

I don't know about interchangability between different models.
The ideal solution would be to get the Cobra diff mount kit and have access to all the gearsets we could desire.
"Ideal solution"= $3k, so it might be a while.

That car's starting to run into some real money. :whistling

Yes, it is.

Saturday she comes for another extended stay in my garage.
We're going to pull the dash and repair the (inevitable) damage we find behind it- primarily wiring and the heater core.
Since we won't know how extensively it's screwed up till we get it apart, there's no real timeline on this job but since I'll have full-time access, we should be able to button it back up by the following weekend.

With the dash reinstalled, cosmetic improvements can proceed on the exterior dash plastic- going to cover it all in black Alcantara (looks like suede)- and a permanent gauge panel. I have a Miata gauge cluster that looks like a suitable candidate but it's hard to tell if it will work until I try.

Meanwhile, as usual, I have a few pet peeves with the car that I plan on addressing while I have it.
#1 on the list is fixing the gas fill door release, which is broken on our car.

Every Mazda in the junkyard uses the exact same setup to operate this door...and of course, the RX7 is completely different and unique.
And stupid/poorly engineered.

It's the perfect example of the lengths Mazda went to to decrease weight in the 3rd gens...instead of using two cables and levers to open the hatch and the gas door, they use one cable to perform both functions, saving maybe an ounce of weight.
The mechanisms attached to the cable are absurdly Rube Goldbergesque and brutally expensive to replace.
I'm going to attempt a replacement using the parts from a 626 (already pulled at the yard, total cost for everything, $5).

Yeah, it's a small thing but it drives me crazy.

No luck yet sourcing a diff, the search continues.

The car is running well on Sigfrid's daily commute, our idle issues seem to have been solved and vibration has been virtually eliminated.
He complains about lack of top end- I have no idea where he's getting the car up to that kind of speed driving to work- but we can address that after the rest of the project has caught up.
He absolutely loves the new brake setup, says it's the best he's ever felt.

Things are looking pretty good overall.

Yeah, the "lack of top-end" is a poser, even given the final drive; two OD gears ought to give a nice chunk of that back.

Valve train is reasonably fresh, isn't it - no weak springs?

What's he turning, or haven't you a tach?

BTW-

The pile-o-parts continues to grow - I just rec'd the turbo rebuild kits for the 13G (standard size on the export/GTO version of the Mitsubishi) turbos I bought (which should be here tomorrow).

I intend to use these to familiarize myself with the data-logging set-up and learn how these things tune.

Should be good for about 50 HP.

I got a super deal on the snails - usually $1200-1300 rebuilt for a pair; I'll have about $375 in these.

Yes, we have a functional tach.
Heads (and all components) are new.
She runs out of steam around 4500 rpm...we're told an LT4 cam (unique to the Vette), ported heads and beefed up valvetrain are what we need.

Now that she's a runner I'm hoping we can get the Vette guys to deal with us.
Last year I took the car by a Vette specialist shop and they wouldn't even look under the hood, had absolutely no interest in working on the car.
Now that we've elevated our game and the car isn't an obvious POS, I'd like to see if we can't get access to their knowledge and maybe even have them build up the motor.

Neither Sigfrid nor I have the background in Merkin iron needed to get this thing right.
We need some outside expertise.

Good deal on the turbos, Kev.
You should get that thing dynoed before you start all this upgrading so you can verify results.

Closest AWD dyno is 300 miles away in Wisconsin.

These have been done to a fair-thee-well anyway; typical stock wheel HP is 240-250 - parasitic loss is large on these.

When we tear into it this fall I'm going to let the compression #s tell the story - if it's fairly uniform and 150-ish, we'll call it good and go from there.

Anecdotally, there is much merit in going with an unmolested stock-block; Matt Monett's Stealth broke into the nines on a 120K specimen - so the story goes.

The way it works is, guys build acceptable platforms - according to a couple of paths/formulae, then tune them (phone advice is easy to come by from the several big shops) well enough to drive them to a dyno-and-tuner (again, the several shops thing) where the badasses make them come alive.

The process is downright incestuous, truth.

It's not a big community - I've already made a few enemies-for-life doing the political thing.

BTW-

Ask S. to tell TJ I will swap him his health-club membership card for whatever historical paperwork he has on the car.

Please.

Just another add:

I've been poking around on the Factory Five site.

Very interesting.

I've been preparing for this weekend by studying wiring diagrams...what a PITA.

It's been fruitful though, I'm beginning to see just how much useless crap is still in the car and how much simpler/more rational we could make it.

Traditionally, Mazda uses one wiring harness for each model and that harness has provision for every possible accessory available, whether your particular car came with it or not, the wiring is there anyway.
From what I can tell, about 90% of our engine bay wiring is completely useless at this point and it would be simpler to start from scratch and remake the harness to include just what we need rather than modify what we now have.
We can relocate the components that are left- mostly relays and fuses- to a less conspicuous spot (I know just where!) and really clean things up.

We'll see how it goes this weekend.

A lovely idea - cleaning things up.

Like to do it with the Stealth, but.

So, I had a productive weekend...if by "productive" you mean "destructive".
End of day two and I don't have the entire wiring harness removed yet...this thing is monstrous.
Sigfrid and I started yesterday morning by stripping the interior, including the dash.
It was immediately apparent that just cleaning up was not going to get it, we needed major surgery.

Modern cars have such incredibly complex and interconnected systems, all of which seem linked to the ECU in one way or another.
We don't have the stock ECU anymore, nor ABS, nor airbags, nor AC...you get the picture.

Anyway, getting everything out means stripping the whole front end off as well, so we end up like this...
http://img.photobucket.com/albums/v78/clocker/Red43.jpg

http://img.photobucket.com/albums/v78/clocker/Red42.jpg

http://img.photobucket.com/albums/v78/clocker/Red41.jpg

http://img.photobucket.com/albums/v7...er/Red40-1.jpg

Looks like fun, don't it?

I really try not to do too much of that type of thing.

I spent a large chunk of Saturday morning inside the Stealth stripping it's interior from the front seats back.

I spent a large chunk of Saturday afternoon extracting myself from the car.

I spent most of Sunday morning moving very (very) slowly.

I really need a small, talented Japanese automotive intern to do this stuff for me.

Quote:

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Originally Posted by j2k4

I really try not to do too much of that type of thing.

I spent a large chunk of Saturday morning inside the Stealth stripping it's interior from the front seats back.

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How come...lose a quarter?

Quote:

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Originally Posted by j2k4

I spent a large chunk of Saturday afternoon extracting myself from the car.

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I know that feeling.

Quote:

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Originally Posted by j2k4

I spent most of Sunday morning moving very (very) slowly.

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Yeah, know that feeling also.

Quote:

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Originally Posted by j2k4

I really need a small, talented Japanese automotive intern to do this stuff for me.

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That's racist.
Can I have him when you're done?

Feeling kind of overwhelmed this morning as I look at the carnage.
It's too late to go back, so I just have to hope that I can figure this all out.

Not really too worried about the engine bay part, that will be tedious but not difficult...it's interfacing with the dash harness that concerns me.

Some of the switches provide power, some provide ground and in at least one case (the main light switch), it does both.
Need to be careful I don't zap anything and burn up the car.

Now there's a pleasant thought to begin the week.

Indeed.

All I need to do now is dope out why I lost power to the antenna (I went back to the extendo-unit because I found a good deal on the OEM units) merely by taking it out an reinstalling it.

Well, the bay harness finally hit the ground around six last night.
I know I sound like a broken record but I'm still boggled by the complexity and extent of a modern day wiring harness.
The harness and associated components- fuse/relay boxes, airbag sensors/actuators, anti-lock brake wiring,etc.- weighs 32 lbs. and is 11' long.

This project is taking a discouraging amount of time, I was completely naive about the complexity and difficulty but hope that things will progress faster now.

I've also taken a few side journeys I hadn't anticipated.
Our GM engine harness and ECU interface with the Mazda wiring at only four points- it gets switched +12v from the ignition switch, and sends signals for the tach, speedo and fuel pump (the latter we don't really need).

During the original swap these wires were hard mounted (crimped/soldered) and had to be cut to remove. I've gathered them together to a four pin connector to make future work simpler...the entire engine harness is now standalone and runs through it's own dedicated firewall grommet so when it's replaced (oh yeah...it needs replacing also!) nothing else needs to be disturbed.

Our battery- relocated to the trunk before I came onboard- had two heavy gauge cables running to the engine, one to the starter and one to feed the fuse box(es) and connect the alternator.
I've pulled one of them (Sigfrid is quite fond of zip ties, I must have cut about two million of 'em to free the cables) and rerouted the other.
Again, it needed to be done but slowed down my work in the bay itself.

Mazda had three large relay/fuse boxes in the bay originally, we now have one fuse box (sourced from a Suzuki Samurai) and standalone/individual relays.
This isn't quite as elegant as the relay boxes but while perusing the junkyard I saw far too many boxes with melted components...one mishap and the whole box is trash.
This way one bad relay can be dealt with individually without messing with everything else.

Of course, the standalone system takes more room and we don't have a lot to spare if the wiring is to be hidden.
I've found a solution that best addresses the constraints I've set and that's my main priority for today. It's unorthodox but clever, I think.
Once the location of the fusebox and relays is finalized I can begin to construct the new harness.

As ever, I remain optimistic.