Project: 1995 Miata

[Mike]

remember: measure 18 times, drill once.

[Maengelito]

remember: measure 18 times, drill once.

or measure 18 times, drill with a small drill bit, then repeat a couple of times using progressively larger bits.

[.RJ]

Drill 18 times. YOLO.

[Mike]

remember: measure 18 times, drill once.

or measure 18 times, drill with a small drill bit, then repeat a couple of times using progressively larger bits.

twss.

[.RJ]

:?:

[Mike]

:?:

[Jake]

Drill 18 times. YOLO.

This is typically my approach to things.

Although, swiss cheesing the floor of my car means I should probably use Mikey's approach.

[D_Eclipse9916]

Drill 18 times. YOLO.

This is typically my approach to things.

Although, swiss cheesing the floor of my car means I should probably use Mikey's approach.

Saves weight.

[Jake]

Boom, installed:



If I hit something and every harness comes flying apart, I blame Bralley.

The rattle is significantly lessened now, after doing what DJ suggested. I think the header is rattling against the firewall or something. Everyone thinks the noise is coming from a different part of the car (front vs rear, particularly) but it's almost completely gone now.

My test-drive last night was very brief, but long enough to confirm that the only thing more fun than a stock Miata with old tires and blown suspension is a completely-modified Miata with seats and harnesses and sticky new tires :thumbup:

[V1GiLaNtE]

Because Race Kah. :thumbup:

[SlimKlim]

Rattle Fix:

Step 1: Remove header
Step 2: Beat firewall with sledgehammer
Step 3: Put header back

[D_Eclipse9916]

Woot!! Great success!

If you want Kaan or I to double-check the harness routing let us know. Its not that hard, but its counter-intuitive the first few times you do it.

Edit:Looked close at the pictures, it looks good from what I can tell. May want to snug up a few, and roll up the excess with a zipe-tie to look better for aesthetics.

[Jake]

Woot!! Great success!

If you want Kaan or I to double-check the harness routing let us know. Its not that hard, but its counter-intuitive the first few times you do it.

Edit:Looked close at the pictures, it looks good from what I can tell. May want to snug up a few, and roll up the excess with a zipe-tie to look better for aesthetics.

Thanks DJ! I looked up routing directions from Schroth or somewhere and it seemed fairly simple. I should have someone snug up the driver's side with me sitting in the seat - goal last night was to get them "mostly okay" so they were tight enough to use. Probably should make them symmetrical and double-check things.

[Jake]

Post-Hyperfest Update -- 118,500 miles ... 450 miles on the swap

So we had the car all buttoned up and ready for Hyperfest on Wednesday night. Still had a slight rattle from (presumably) the header but otherwise ran great. I hopped in on Friday morning and drove down to Summit Point. The seats are tight for long drives. I think a small pillow for my back would increase comfort for drives to VIR and the like. Highway driving is great, no drama.

Pace laps were also great. On the "run away from Time Trials" laps, I could touch 90-95 mph as I dove onto pit road.

Sunday afternoon, I asked Maeng to hop in for some pointers while I took a few hot laps of the entire track to see top speed (since pace laps never involve the front straightaway) and do more shakedown. We made it through the pace lap, got the green flag, and by turn 9, I've got the throttle buried in the carpet and I'm redlining 3rd. Pull into 4th and bury the pedal again, and it just sits at 6k, going 80 mph. Absolutely will not go 81. And the temp gauge is creeping up a little bit (usually it sits a tick below halfway, this was a tick or so above).

We pulled in, let it cool off, discovered a PCV vacuum line that I had disconnected and forgotten to plug back in, and took it out again. Same problem.

Decided maybe this has something to do with my check engine codes. Pulled them again and discovered I'm reading them wrong. It is throwing three codes, all decipherable this time. It's throwing "04 - SGC Signal," "09 - Engine coolant temperature sensor" and "16 - EGR function sensor."

Joey and I accidentally grounded the coolant temp sensor wire when the motor first went in, thinking it was an engine ground. I'm wondering if we screwed something up there. A new sensor is like $16 though.

Compared my EGR to that of another 99... and I'm missing a plug entirely. I have a wire coming off the car's harness with no mate, and that receptacle (which hangs off the EGR) is just sheared off. Oops? Guess I need to replace that. There is also a vacuum line that I need to run, now that I know where it should go.

So, basically, my guess is that as the car is being driven hard for multiple laps, the coolant is getting hot and the ECU doesn't know what to do (because the temp sensor is FUBAR) and retards timing, in a sort of "limp" mode. The missing EGR can't be helping anything, although I doubt it's hurting much either. The "SGC" refers to one of the signals coming off the Cam Angle Sensor. Wondering what's up with that.

Overall, great weekend with the car. Just need to sort out some teething pains.

[Jake]

Was bored last night, so Bralley and I snagged a new coolant temp sensor from AutoZone and popped it in. Easy job - just remove coil pack and unplug wires to coil pack and CAS. Takes a 19mm wrench but easy access.

My car is a 1.8, not a 1.6, but this photo is accurate enough:



The one with the green plug is what we replaced.

Reset the ECU via battery disconnect, took the car out for a spin and did our best to initiate "limp mode" on Route 28 (high RPM, high speed, long-ish periods of time) and couldn't do it.

Two of the three codes went away. All that's left is the EGR code - not surprising given the um, sheared off EGR system.

[V1GiLaNtE]

Interesting... That was the one sensor we had to remove a handful of times to get to that gasket..

[Jake]

Interesting... That was the one sensor we had to remove a handful of times to get to that gasket..

Yeah. I have no idea why it could have suddenly failed, considering it worked fine on the old motor. I'm wondering if it got dropped a few times on the concrete floor, and maybe something broke internally.

[Jake]

Post-VIR "Heat Wave" Update: 119,200 miles (1,100 on the swap)

Other than the pain of leaving Northern Virginia at 5 PM on Thursday to go south with everyone else who commutes from too-far-away to work up here, the drive to VIR was pretty pleasant. I ran the AC for the first two hours - very glad I kept it after the swap - and dropped the top in Charlottesville. The motor is rev-happy and feels strong. Over the ~220 mile drive, I managed 29 mpg, even with the AC running part-time. Not bad at all, although five hours of this does get tiring:



Friday and Saturday had everything running great. A few rattles and such, but nothing strange. On the "run from time trials" pace laps, I was able to get up to 105ish easily. Well, as easily as a Miata can Even in the super-hot weather, A/C on or off, it was staying right where it should on the temp gauge:



Maeng went out with me on Sunday in HPDE 3, to evaluate my driving for a Time Trials license (which, I believe I did pass, yay!). We got probably four laps in with some good speed on the straightaways (100+ mph). The fifth lap, I felt a noticeable lack in power and could do just shy of 90, max. Engine temp creeped up by about a needle's width above the center mark. This was around Turn 2, so we had to make a full lap anyway to pull in. At T3, I stopped for a red flag drill. As soon as I stopped (clutch depressed, 0 mph), the engine just gently cut itself off. I restarted it, and the same thing happened. Had to give it throttle (just a quick blip) to make the ECU realize "hey moron, need to you idle here" and then it was idling fine again.

We came in after that red flag drill. I've posted to Reddit and Miata.net, and the common thoughts are "new thermostat" and "different coolant mixture, with Water Wetter added." The T-Stat is lord-knows-how-old -- it came with the 99 motor -- and I'm running 50/50 pre-mix coolant. Someone suggested 70/30 mixture with WW on top of that. He also mentioned that the ECU will automatically retard timing in extreme heat, which is what this felt like.

Track/Miata folks, any thoughts?

The CEL is still on for the EGR shit that I haven't taken care of yet.

[JPolen01]

I always look forward to your weekend reviews. Glad to hear the miata held together and congrats on the TT license!

[navin]

Stock radiator? If so I had the same type of overheating in the Civic with a dual-core OEM radiator, swapped out to a blingy aluminum one and it cools just fine now.

You can pick up the cheapo ones on ebay and they work just fine, Mishimoto or whatever. I never had much luck with the water-wetter combo to be honest, car still over heated.