Two 1990 Miatas - STS Autocross, CSP Hillclimb, PR Rallycross

Wiring complete.

Car doesn't start now. Yay.

Need to determine what cards exactly these are. They match all the conventions and wiring colors as the track dog cards but evidently there is different software loaded depending on the year they are meant for. Plus I haven't found instructions with an exact image match for these cards. I am suspicious they are for a 94- 97 but no way to confirm that.

Based on the instructions I have found from moss, which are not these cards but similar, the ignition card should have a light run back and forth and then stay green. Mine just runs back and forth indefinitely.

Autocross at Pocono today, will do more research and reach out to TDR later.

The cards, in case anyone recognizes them:

Confirmed they are Moss cards, but having a heck of a time finding Moss install and troubleshooting instructions for anything except their 6-wire version of the fuelcard.

I did find posts from Jason@Moss circa 2009 answering someone trying to run a used '01-05 M62 card on a '94 with an M45. He indicated that it should work electronically and have enough adjustment range to tune properly despite the different base software. So I am optimistic that my card should work on a '99 and I must have made a wiring error somewhere.

https://forum.miata.net/vb/showthread.php?t=335153

Related: Tom @ FastForwardSuperchargers is incredibly helpful despite me not spending any money with him yet. Two thumbs up.

Oh. Tires. Quick comments for now:

I subjectively like the Nexens but once conditions allow RE71's to get good'n'hot, I still like those more. I can do a full writeup from my notes later if anyone wants, but the verdict is basically that when the temp is less than ~80 and/or damp/cloudy/windy, I'd pick the Nexens. They allow much more recovery from driving mistakes than cool RE71's, and are fast from the first run. However for a two driver car, 75 second runs, 5-7 minutes between runs, once the sun came out the Nexens absolutely melted and would need a sprayer. With said sun out, we pulled a pit stop tire change in 8 minutes in grid to put the RE71's back on and for the second time this season I felt like the car was doing what I wanted. The first time was the day before on cold Nexens.

Note that I like RE71's hot. Like, really friggin' HOT. I'm one of those nutcases that thinks they don't get slow, they just get 'different'. Codriver hates this feel so we were spraying before his runs and not for my runs. We both felt we drove well.

• In general on RE71r for this whole stupid cool-weather season we've been having, I have been ~2 sec in 60 behind him struggling to drive and occasionally getting lucky.

• On Nexens, his times were still good relative to our benchmarks, and mine were only ~1 sec in 60 behind him and felt like the car was doing what I asked.

• With me on hot RE71 and him on sprayed RE71, times were dead even between the two of us for the first time this season and I beat a bunch of people I'd been lagging behind lately.

Also the 225 Nexens look really badass on the Miata. That was the #1 comment of the day.

This is after (18) 75-second runs. Noticeable wear but it is even and consistent. And that's after the equivalent of NINE 4-run local events for a single driver. The wear is plenty reasonable.

....and proper instructions found which seem to indicate the wiring of the timing card is to be the opposite of how the TDR instructions lay it out, or at least the opposite of how I read them.

Based on TDR instructions, I did:

Channel 1 Yellow In From Harness

Channel 1 White/Yellow Out to ECU

So, solids to the car side and stripes to the ecu side.

Jackson/Moss instructions:

Connect the Yellow wire, of the TimingCard, to the Brown/Yellow wire leading to the ECU connector. Connect the White/Yellow wire, of the TimingCard, to the Brown/Yellow wire leading into the harness.

So that says 'solid to ECU side' and 'stripe to harness side' which is the opposite.

Great...now I can't wait to get home but I am supposed to prep the 3 for a track day tonight. :-/

Edit: Gary @ TDR confirmed that the above was in fact an error in their online instructions, though he noted that when they produce harness/card kits they are wired correctly :D

Yep, that took care of it. Up and running now.

Couldn't make TNiA due to work, so I was out in the garage for 2.5 hours last night. Throttle bodies in place, wiring rerouted and rewrapped as necessary, throttle cable arranged, pullies/tensioner in place, header blanket roughly installed and wired in place, SC oil changed, and ready to set SC in position as soon as I trim the DS heater hose to clear the intake pipe. Needs to move back about an inch. Seems like people trim the hose, replace the hose, smoosh the hose, or make their own plastic intake plumbing. I'll be proceeding in that order.

Ended up replacing one heater hose and using a sawzall on the flying buttress to get the inlet pipe to fit:

Everything has now been installed and fits, then disassembled to screw with belts and tensioners. I need a belt in between the two lengths I had on hand, that should be here on Friday.

I also need to clean up how the MAF and air filter sit/fit under the hood, and maybe extend the MAF wire depending where I mount it.

It started right up, runs, idled, revs, moves the boost gauge, etc. Got to that point with five minutes to spare and today is you to be a VERY long day at an amusement part with family before I can go clean up some wires and hoses and take it for a drive tonight. Maybe. Arrrrgh. Can't wait.

Oh. My.

The noise is just fantastic. Might even be better than the power. 'tuning' is done and AFR is happy at 11.5-12.2 all the way through the powerband. Boost is 6.5-7 psi +/- the accuracy of the $19 Bosch gauge which does at least rest at 0 with engine off FWIW.

Both cards, the rats nest of hoses and the two gauges are currently zip tied to the center hvac vents/eyeballs. It's pretty awful. But I wanted to get driving ASAP. I put about 20 hard miles on it tonight and nothing broke yet but there may be a substantial (more substantial?) oil leak. Will look at it tomorrow.

Seeeee? It makes noises!

https://www.youtube.com/embed/Obdgutq5c8M

I LIKE that.

So...6.5 to 7 psi at lower rpm...by 5000 it's more like 6.0 psi...by red line 5.5 to 5.0 psi. Belt slip, I am guessing?

Definitely belt slip. Lots of black dust. Will work on that next week.

Green (as in, definitively from the supercharger) oil in the intake/crossover pipe though...that might suck.

What the heck, I drove it to work today. The car will probably have a lot of down time in the next few weeks so may as well enjoy it for now.

....berkeley it. Still driving it. Could be bad seals, could just be overfilled. Am checking the intake for oil daily. When it stops appearing I'll take the sc off and pop the nose off and confirm the oil level. If it's ~none then it's rebuild time. If it's ~correct, then the leakage was just overfill.

Have located rebuild kit for $130ish and a place that asserts I can do the rebuild myself with care or they can do it for $200. Other places charge $600ish for the whole deal and assert that welding is involved. Not real clear on the details other than that these are both supposed to include all the bearings, the shaft seals, etc - it isn't that the cheap place is quoting just the nose bearings. But I'll cross that bridge when I get to it.

There's an odd occasional lean condition and bog not under boost but on moderate throttle tip-in at 1500-2000 rpm when the engine is not fully warmed up. If I understand correctly the fuel card shouldn't be doing anything at this point anyway. Feather the throttle to above 2000 rpm and then floor it, no problems.

Still need to rework that belt tensioner. Should be easy enough, just need to stop driving the car for a day or two to do it!

Interestingly...the appeal of the power wore off faster than I expected. On the roads around here even a bone stock Miata can quickly and easily get to unsafe speeds, nevermind the speed limit. So now I can get from 30-65 even quicker and occasionally squirt up to 90 with minimal effort. And then realize this is stupid and slow back down. So in conclusion I am very glad I went this route rather than picking up an entirely different vehicle with more power - something I'd been considering for a while. Because with the Miata the 90% of driving that is at responsible speeds limited by traffic, laws, deer, bicyclists, potential gravel in corners, and so on...it's still a Miata. If I'd gone out and bought a fox mustang with the same power:weight I'd be mighty cranky right about now, I think.

Finally sorted out the belt tension issues mostly, by adding a hole to this hacked together tensioner that moved its miniscule adjustment range to a usable one.

With that done I can now blip the throttle by hand and see the couplers all bulge and the boost clearly comes in quicker when driving. Furthermore, saw a strong 7psi. Two acquaintences ppinted out that 5psi is typical and my cheap gauge might be cheap.

So I checked on this...stock pulley is 67.5mm

So that was a nice surprise.

Ordered plug wires today. Still need to install new plugs and valve cover gasket to stop the absolutely epic leakage from it. Sorry, sorting out boost had priority.

210,000 miles today.

Alright I think I found out why the valve cover leak seemed much worse than your average valve cover leak:

New one installed this weekend and the car no longer smells like a refinery fire at every stoplight. I might feel comfortable removing the fire extinguisher from the passenger seat now too. I parked in a previously-unsoiled parking spot at work today and hopefully there is not a big puddle under the car at lunchtime anymore.

The fuel card went into "I have no injector signal" mode this morning after a coffee stop restart, but seemed to be still adding fuel in boost. After about a mile of gentle driving it woke back up and behaved normally. Will have to keep an eye on that.

The belt tensioner setup has been further tweaked and tension is now good. No more power steering kickback/slippage, no new belt dust after 25 miles. The good Gates brand belt is also here so I'll put that on shortly. I am still using the crappy adjustment mechanism that came with the kit so I might need to swap pulley diameters when installing a new belt, until it stretches a bit and then reinstall the larger idler pulley. About a 5 minute job.

Boost is still strongest from 4000-5500 rpm and then tapers off to more like 6.5-6.0 psi on the gauge. From what I am reading that would be pretty severe belt slippage, so I am wondering if the cause is simply the engine catching up to the blower volume either because of VICS or because the blower is actually being slightly overspun at ~15,000 rpm rather than its rated max of 14,760.

Oh, yeah, the car is signed up for an autocross on Thursday.

Plans to autocross the SC'd NB have failed so far. The thursday event mentioned in the previous post, well, someone offered me a drive in a BSP Mazdaspeed Miata that I couldn't turn down.

Tried again this past Sunday. Went to start up the car for my heat and the damn fuel control card would not wake up/initialize/etc. So I drove an ES '99 Miata followed by a 2017 Chevy SS that was A WHOLE HELLUVA LOTTA FUN. mmm power. But no SC Miata :(

So I go to start up the car planning a slow, gentle drive home outside of boost...and the card comes right up. Once it is up and running it will work indefinitely. but every startup is a crapshoot. None of the companies that deal in these cards recognize that behaviour as, well, anything at all. So I guess I can check all the wiring, try swapping ECU's in case something funny is going on with open/closed loop, cold start protocol, or whatever...after that is ruled out I'll try popping open the card and see how the board/solder joints look but I bet this leads to ponying up $300 for a new card in the end.

Oddly enough, the wear point in these things is understandably the rubber diaphragm or whatever that senses boost. But this has no issue sensing it very consistently and accurately once it electronically decides to work so I am pretty sure this is an electrical issue of some kind, not a loss of boost signal or self-calibration issue.

Connector issue? Broken solder joint?

I mean that's what I'll be checking but if that's the case I find it really odd that I can not ever get it to fail after it has begun working. I mean I can beat on the thing mercilessly for an hour in 95 degree heat and it is fine. As long as it initialized in the first place. This includes physically slapping around the card, ecu, and all wiring connections

Current solution is drive it till it breaks. Have some safety wire on hand to wire open the boost bypass if it REALLY breaks far from home.

-Midsummer apathy is in full effect:

-The fuel card always wakes up after a few tentative crossovers into boost. Now that I know how to instigate it into working, I'm ignoring the problem.

-The oil leak has moved to the front main seal but it's stabilized now. I'm ignoring the problem, though I did order another bottle of ATP205.

-The ancient upper rad hose started leaking so I tightened the (screw) hose clamp.

-The supercharger clearly needs to shift rearward about 1/8" for belt alignment. Need to trim a few things. Left it alone. After after driving in the rain the belt will skip a rib rearward on the blower nose pulley. It stays there, builds boost just the same as with 4 ribs, and at this point the belt is worn in to that shape. So until I get around to upgrading the awful tensioner, I am ... ignoring the problem.

-Still no 'idle droop' or driveability issues but after coming to a stop for a few seconds the idle will bounce from 1200-500-1200 about 5 times and then stabilize. So I am - wait for it - ignoring the problem.

-1000 miles on the SC setup in the 6 weeks since installation. Tons of fun. It's deadly in the rain even on 1000-mile all-season tires. I've gotten in the habit of keeping the A/C on as a means of traction control. It takes the edge off just enough that rolling into the gas around a corner at 40 mph in 4th gear no longer requires countersteering.

I finally sold some of the parts that came with the deal so the challenge budget of this thing as it sits is roughly $2600. I don't want to sell the spare engine but I think there's enough other parts from the original deal that I can sell to get it to meet $2017. Since I can't go to solo nationals I am sorta considering the challenge, if the car is still running well in a month.

After several disappointing autocross events where i felt i did not drive well, this weekend i finally got an overall win this season. My codriver was only 0.052 behind so the car finished 1-2 for the event. First time we have managed to pull that off.

https://www.youtube.com/embed/YupDGG-hXws

Drove around a bit playing with fuel and timing in the NB. End result was a 0- 60 time of 6.4 seconds with a fair amount of wheelspin on the launch as well as the 1-2 & 2-3 shifts. 30- 55 mph time of 2.9 seconds.

Also finally caved in and bought a megasquirt for the STS car. It'll be here next weekend. I have zero experience with this and hope to have it up and running for an event on the 16th.