Year: 2017

Fuse/relay box and power distribution are now mounted and installed. Needed a bracket for these items so I made this:

Installed:

Also made the 6ga cable for starter to alternator :

The revised spacers for the control arm spherical bearing kit arrived. The kit is made by ESM Race up in Canada. I originally found the bearing spacers for the rear lower outer position were the wrong ID and length. It took them a while to get the corrected bits to me but, to be fair, just about every machinist I’ve known seems to operate on a different calendar than the rest of us. At any rate, parts are here now and right. I’m checking with them now to ensure that any Miata kits they make in the future have these corrections.

The final hitch was in the rear upper outer; the V8R arms have the cool feature of using an eccentric bolt there to adjust camber quickly without affecting toe, but the eccentric bolt is larger in diameter than the normal bolt in that location so the ESM bearing spacers for that spot didn’t fit. Not ESM’s fault, just particular needs of my setup. Had a local machinist drill those spacers out to match the eccentric bolt diameter and now everything is in:

Back on the lift and continuing to tick items off the list. Today I ran the main battery cable and engine grounds. This motorsports grade cable is awesome stuff and super flexible:

Out front for our tech day at the shop. Starting to look more and more like a car. Still many items on the to-do list but it felt great to have it out there even just rolling. We’re getting there!

The final hurdle before our tech day was the axle boots rubbing the lower lock collar on the rear coilovers. The boots can be compressed a bit to improve clearance but I want to make sure this area is smooth and doesn’t have anything that could damage the boot if they do make contact. Changing to a ring/collar that takes a pin type spanner wrench instead of the current notched rings I have would do the trick, but there wasn’t enough time to source one among all the various shock body sizes/thread pitches out there.

Called Feal up and they sent down a spare lower shock mount… looks like it belongs to a Subaru or similar. That’s perfect, all I needed was the threaded top portion. Cut two rings off the top to make new lock rings from:

Cleaned up the rings and drilled four holes in the outward side of each ring juuuust shallow enough that they didn’t go through to the inner threaded side. Then we couldn’t find the pin type spanner wrench at the shop so I threw a quick and dirty one together:

The lock ring now clears the boot, has the same OD as the lower portion of the coilover and has a smooth outer surface in the event of contact:

And with that I installed the rear coilovers and then the wheels and set her on the ground for the first time in a year! Tomorrow she’ll be out in front of the shop for our tech day.

Before the weekend I need a steering wheel! Steering wheel needs a steering column, that means I need the dash… and if that’s going in I should get the IQ3S display mounted as well.

Needed a bracket to hold the IQ3S so I made this:

It piggy-backs on the two bolts holding the steering column to the dash bar and is slotted for adjusting distance from the steering wheel and vertical placement.

Still much to do in the inside of the car but now we’ve got a dash, digital display and steering column all mounted up and ready for a steering wheel:

2021 UPDATE: This bracket later evolved into production versions that can mount most popular digital displays/loggers in a Miata:

Singular Motorsports NA/NB Digital Dash Bracket

Taking a detour for a bit, our tech day at the shop is coming up this Saturday and a couple days ago I realized that April 1 will be the one year mark to the day from when the car rolled in to the shop and the old engine came out. Decided the car should be on the ground and on display out front on that day!

So, the next couple days will be a bit of jumping around with random updates as I prioritize just the things needed to get the car on the ground.

Front Suspension

Clearly we were in need of some suspension to set the car on! Installed the following:
Feal 442 coilovers
Control arms with spherical bearings
Spindles with fresh hubs
R package tie rod ends
V8R upper rebuildable ball joints
Bauer extended lower ball joints

Notes…
– haven’t sorted out the front sway bar yet but don’t need that for Saturday.
– V8R front upper ball joints are tight until they lap in (takes a couple hundred miles). Correct assembly is to torque top cap down then back it off one “notch” of the lock ring and then install the lock ring. Reset the lash after first track day or 200 miles.

Setting the shock length/bump travel in the front (done with spring removed from the shock assembly):

Driveshaft

Installed the driveshaft with rear subframe and differential. Has to be done together as the Getrag has a long shaft on the flange to the driveshaft that the driveshaft slides over, so you lower the diff about 12 inches, install the driveshaft and then raise the diff with the driveshaft attached.

The CV joint on the driveshaft gave us some trouble, the CV wants to spring apart and has to be held together while installed. During first install something came unseated inside and the bearings locked up. Quickly evident as the drivetrain wouldn’t rotate because the CV was locked at one angle. Had to disassemble/reassemble the CV (and order the proper CV grease) and then reinstall. Everything is in and happy now. Forgot to take a pic.

Axles

V8R Stage 2 axles – first off, examining these in person they are very nice pieces.
Comes marked as one long and one short. Long one goes on the right side. The CV joints in these are packed with grease and the grease can keep the CVs from compressing fully so at first it appeared the axles were too long. Pulled them out and worked the joints around while putting body weight on them and they shortened up a lot and then installed fine.

Current state of affairs in the rear:

So, axles, hubs and spindles are in along with the V8R upper pro series control arms. What’s NOT in are my lower control arms complete with spherical bearings. The placeholders right now are factory arms with rubber bushings that were laying around.

This spherical bearing kit had some dimensional issues in some of the rear pieces. Unfortunately the company who makes the bearing kit has been working at a snail’s pace to make the necessary changes. As this kit is here for evaluation, this makes it hard to recommend it, but hopefully that stuff will get sorted out soon. As a last resort I can have the existing pieces machined to work right myself, but they assure me they’re working on corrected pieces. We’ll see, but for the moment these loaner rear lower arms will get the car on the ground.

Ran into one more hurdle in the rear. The beefy axles are larger in just about every dimension than stock Miata axles. Where the axles passes by the coilover, it’s very tight. There’s juuuuust enough clearance from the CV boot to the lower cup on the rear coilover, so that is OK but the lower lock ring on the coilover has a larger OD than the cup below it and that ring hits the boot:

Can’t have these two bits contacting with the axle spinning of course. I believe I have a solution figured out, Feal is sending over some parts that I think I can modify to make a custom low-profile lock ring out of. That stuff arrives Friday.

Fluids

Final thing tonight was getting fluid in the trans and diff since we’ll be rolling the car around.

Trans is 75W90
Diff is 75W90 + 4oz Limited Slip Additive. Sounds like snake oil to me (sarcasm) but OK we’ll follow the spec.

Got the USM (Universal Sensor Module) sorted. The USM is a four channel add-on to the Racepack digital dash allowing the addition of any sensors you want. Black box in the pic below:

The USM is why I finally took the plunge on a digital display. The original plan had been to add at least two more Accutech SMI gauges to the two I already had in the car so I could keep track of temperatures of all the various important bits. I realized I was heading down a path to having a very busy interior with a lot of things to try to keep an eye on.

The digital dash simplifies everything into one place where I can program warnings for each input and leave the dash to monitor things while I just drive. The dash pulls most of the engine vitals info I need right through the OBDII but the USM makes it possible to add the extra sensors I wanted and simplifies the wiring by transferring everything to the display via one V-net cable.

The sensors are already installed in their various locations, documented earlier in this thread. Now, on to wiring up the sensors to the USM. Here I’m using milspec /32 wire same as previously, but this time in 22ga twisted pairs. The twisting is a method of shielding the signal from interference. Frankly, you don’t need it for these types of sensor’s signals but here I used it because it helps keep things tidy:

Wiring within the USM box. The USM has a strain relief feature on the inlets which is a nice touch; tighten the outer nut and it clamps down on the wire to secure it in place:

The finished USM harness:

Mounting the box was done on the top/rear of the engine via a pair of simple brackets. Yes it’s tight back there. This is mounted to the engine so that all the sensor wiring can stay with the motor when it’s removed, just disconnect the single V-net cable connector:

With the box mounted we just need to run the V-net cable to the display. This could be done with one long cable that would need to pass through the firewall, or a bit cleaner version here that involves two shorter cables and a bulkhead connector:

Tidy!

The remaining wiring to be done was to tie in where necessary on the GM wiring harness. Most of this was coming through the firewall from the chassis harness – things like ignition switch, start button, lights, fan, drive by wire throttle, OBDII, etc.

I blasted through this and forgot to take all but one picture – V8R advised that the throttle pedal signal is very sensitive to interference, so for this I ran a 6-wire shielded cable on both the chassis and engine side:

The rest was just patching stuff into the existing engine harness. The stuff I added is all on par with what I did on the chassis side, but I’d love to re-do the entire engine harness in the future so that it is all up to higher standards. However, for now it’s a good working harness and this thing needs to be running!

All of the wiring interface from chassis to engine converges in the rear right corner of the engine bay. Everything is set up to disconnect from the chassis quickly/simply and comes out intact with the engine. There’s only four total things to disconnect, all located here: main bulkhead connector, v-net connector, engine ground and one M6 bolt that holds the fuse/relay plate to the firewall. Not trying to hide wires or tuck anything away, the goal here is easily accessible and quickly removable:

Switching gears a bit, this car will need some serious brakes… and they arrived!

Newly released 11.75″ BBK with Stoptech billet STR42 caliper. Ohhhh yeah baby, track testing can’t come soon enough!

Paired with my AP Racing J-hook rotors on aluminum hats:

Continuing on from the last post…

Here I’m beginning to loom the harness with a combination of the fiberglass braid plus short lengths of adhesive tube that will later be shrunk down over the ends of the loom to prevent fraying and seal the wires where the harness splits. You can see that assembling the loom requires a good bit of forward-thinking because each section often needs several more various pieces sleeved over it that will be shrunk down later:

Also in that pic is the bulkhead connector already assembled. That connector contains each wire that will pass from through the firewall into the engine bay, which makes it very quick and easy to disconnect the engine side of the wiring from the car so the engine can be pulled quickly without having to disconnect the wiring harness from the engine.

With beginning to pin wires into connectors we can cover the final piece of documentation; diagrams and pin layouts for each connector in the harness. When I began the harness build this sheet had blank spaces next to each pin, and I filled the sheet out as I assembled connectors:

Looming an engine harness is rather straight-forward as nearly every wire begins at a common datum (usually the ECU). Looming a chassis harness can be a bit more complicated since you have wires doing a lot of back-and-forth from switches to fuses to devices etc. In my case, I planned to put the fuse/relay box and a distribution block for power and ground on the passenger side of the transmission tunnel for easy accessibility. Also along this same area of the harness I had multiple breakouts for connectors that would go to the switch panel. This all made for a dense bunch of splits all at one point requiring a bit of work to tidy up and seal.

Here the wire is as condensed as possible and wrapped in kapton tape, ready for the Raychem ATUM to be slid over and shrunk to seal the breaks:

And with the breaks all sealed up:

After the loom is in place the last step is pinning the wires for the connectors. There are a few popular options for connectors with different strengths. I chose to use the common weatherpack and metri pack connectors for ease of service. Each wire has a seal that is assembled with the terminal so that the wire itself seals to the connector – the benefit here is this eliminates the need to seal the whole backside of the connector. In this pic you can also see the short sections of clear shrink tube that are put on each wire before the terminal is crimped on and will be shrunk over the labels afterwards:

Terminals inserted into connectors, connector sheet updated with which wire went in which pin position and each connector’s name labeled on the loom behind it. These are the connectors that go to all the engine and auxillary control switches that will be on the center console:

Similarly finished ends that go to the fuse/relay box:

There were a few other connector types used for the harness as well. Some were OEM connectors that had to be re-used, and then there was the connector that goes to the Racepack IQ3S dash. This is supplied by Racepack with an extra long pigtail made up of standard cross-link wire. I needed to de-pin the connector and then rewire it with the milspec stuff:

After some digging I found this is a Motec M800 34-pin connector. What do you know, ProwireUSA has pins for those 

Here’s the connector, new and improved:

For fuses and relays I chose this trick little combo box that takes both mini fuses and micro 280 relays. It uses metri pack seals and connectors:

Beginning to wire the box:

After much work, here it’s tidied up with service/strain relief loops on each wire:

The finished fuse/relay box and harness. The ring terminals go to a bus bar for power distribution and grounds. I put this whole assembly on connectors rather than build it into the harness so that it can be removed for service or additions without the need to take the whole main harness out of the car:

And after much more work, we’ve got finished harnesses, ready to go to the shop for install.

Main chassis harness (connectors to Racepack dash, OE brake pedal , GM gas pedal, fuses/relays, OBDII, all switches, tail harness, diff temp sensor harness) :

Power and ground to bus bars:

Tail harness (connectors to chassis harness to fuel tank, rear lights, and grounds):

Diff temperature sensor harness:

Engine control switches:

Racepack dash page toggle buttons:

At the shop, everything ready to go in. Oh, and this saves 10 lbs over the old wiring that was the already hacked and trimmed down factory harness: