Scooter - A Miata Journey and ITB Noises
#101
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#102
Cpt. Slow
![](/mt2011/images_td/ranks/supporter1.gif)
iTrader: (25)
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 14,285
Total Cats: 1,163
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I've found I break (or slightly damage like you did) 50% of used OE connector lock tabs, where as I break almost no aftermarket/new connectors like from Ballenger or others. Not sure if that's because they're old and crusty, or just built with tighter tolerances "back in the day".
I work with a lot of BMWs of similar age, and their connectors come apart much easier. More than likely it's because mechanics have been tracing wiring faults or replacing components more often than the Miata!
I work with a lot of BMWs of similar age, and their connectors come apart much easier. More than likely it's because mechanics have been tracing wiring faults or replacing components more often than the Miata!
#104
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This weekend was extremely busy, but I got to spend a good amount of time with the car. First, I figured out the CAM sensor wiring. It was a bit tricky to crimp the pins with the tools I have, so might need to get nicer tools for future projects. Any recommendations here? I'm using the IWISS stuff from Amazon. Would like a crimper that can do OEM style pins and these splices too: https://www.prowireusa.com/p-3226-op...ose-piece.html .
That said, it all worked out. Forgot to take pictures, but also changed all the VVT o-rings and gave it a new valve cover gasket. The VVT kit I bought was missing the solenoid o-ring, so have to order one of these. It's only held by one bolt and doesn't affect any other component, so it's ok.
It was at this time that I realized the VVT connector I had purchased was for an NC
. Ordered the correct one from Ballenger and should be here later this week.
While cleaning the ITBs I noticed that the throttle cable has been eating away at the aluminum adjuster. I guess I'll need to get another one eventually, maybe in delrin or steel? Not too concerned for now, but added to the list.
![](https://i.imgur.com/mLWvI5e.jpg)
![](https://i.imgur.com/WBMvsoW.jpg)
Moved on to rewiring the coil harness for the R8 coils (just two wires here). I bought a kit from GFBDevelopments across the pond, because I liked their wiring work from the Denso COPs I ran before, and wanted to save myself some time. Unfortunately, I gave them backwards nomenclature for the coil 3/4 connections so that's what I had to rewire. Easy job; Used a Deutsch DT for it. Changed the dwell to values Adamw from the Link forums has used. Here they're in case someone is interested:
V - Dwell (ms)
08 - 5.9
09 - 5.3
10 - 5
11 - 4
12 - 3
13 - 2.2
14 - 1.8
15 - 1.6
16 - 1.5
![](https://i.imgur.com/KulH5IE.jpg)
Did a test and all 4 fired in the correct sequence!
On to plugging the OEM injector holes at the head aaaaaaand the freeze plugs are too small. I took some measurements and it seems the BP-6D injector holes are about 0.5mm wider than the BP-4W, so the freeze plugs I used last time won't work. The only solution I could then think of was to tap the holes and use NPT plugs. The hole seemed to be the same size as a 1/8 NPT, but long story short, they didn't get snug. With guidance from my friend Tim, I drilled and tapped to 1/4 NPT and that did the trick! Turns out Quinn also did this to his BP-4W head. A bit scary doing my third tap job on an aluminum head, but they turned out great!
![](https://i.imgur.com/XAtt7bU.jpg)
1/8 NPT plug
![](https://i.imgur.com/M4nLlU8.jpg)
OEM hole
![](https://i.imgur.com/Tt79NVp.jpg)
Drilled injector hole
![](https://i.imgur.com/LTY6uBI.jpg)
1/4 NPT plugs installed
Nicer plugs are on their way, but these must do for now. At this time I also refilled the trans with Motorcraft unicorn tears hoping it would help some of the shift feel the trans has lost, filled the turret, and put the shifter back together.
![](https://i.imgur.com/Qa541ae.jpg)
After some more wiring cleanup and future planning, it was time to test the cam/crank sensors and make sure the ECU was happy/synced. I took a log and trigger scope while cranking with no fuel/spark.
![](https://i.imgur.com/XaaK3f1.png)
SUCCESS!! ECU saw the cam/crank, and had sync. That concluded the night, and today/tomorrow I hope to have the engine started. I say that because the exhaust is still off, some more wiring to do, and the O2 sensor is unplugged. I also saw no oil pressure while cranking yesterday. I hope it just needs more time to prime as it is a fully empty pump and all. Also, today is Tuesday and I want to hit the trails!
![](https://i.imgur.com/EF3qhWL.jpg)
That said, it all worked out. Forgot to take pictures, but also changed all the VVT o-rings and gave it a new valve cover gasket. The VVT kit I bought was missing the solenoid o-ring, so have to order one of these. It's only held by one bolt and doesn't affect any other component, so it's ok.
It was at this time that I realized the VVT connector I had purchased was for an NC
![facepalm](https://www.miataturbo.net/images/smilies/facepalm.gif)
While cleaning the ITBs I noticed that the throttle cable has been eating away at the aluminum adjuster. I guess I'll need to get another one eventually, maybe in delrin or steel? Not too concerned for now, but added to the list.
![](https://i.imgur.com/mLWvI5e.jpg)
![](https://i.imgur.com/WBMvsoW.jpg)
Moved on to rewiring the coil harness for the R8 coils (just two wires here). I bought a kit from GFBDevelopments across the pond, because I liked their wiring work from the Denso COPs I ran before, and wanted to save myself some time. Unfortunately, I gave them backwards nomenclature for the coil 3/4 connections so that's what I had to rewire. Easy job; Used a Deutsch DT for it. Changed the dwell to values Adamw from the Link forums has used. Here they're in case someone is interested:
V - Dwell (ms)
08 - 5.9
09 - 5.3
10 - 5
11 - 4
12 - 3
13 - 2.2
14 - 1.8
15 - 1.6
16 - 1.5
![](https://i.imgur.com/KulH5IE.jpg)
Did a test and all 4 fired in the correct sequence!
On to plugging the OEM injector holes at the head aaaaaaand the freeze plugs are too small. I took some measurements and it seems the BP-6D injector holes are about 0.5mm wider than the BP-4W, so the freeze plugs I used last time won't work. The only solution I could then think of was to tap the holes and use NPT plugs. The hole seemed to be the same size as a 1/8 NPT, but long story short, they didn't get snug. With guidance from my friend Tim, I drilled and tapped to 1/4 NPT and that did the trick! Turns out Quinn also did this to his BP-4W head. A bit scary doing my third tap job on an aluminum head, but they turned out great!
![](https://i.imgur.com/XAtt7bU.jpg)
1/8 NPT plug
![](https://i.imgur.com/M4nLlU8.jpg)
OEM hole
![](https://i.imgur.com/Tt79NVp.jpg)
Drilled injector hole
![](https://i.imgur.com/LTY6uBI.jpg)
1/4 NPT plugs installed
Nicer plugs are on their way, but these must do for now. At this time I also refilled the trans with Motorcraft unicorn tears hoping it would help some of the shift feel the trans has lost, filled the turret, and put the shifter back together.
![](https://i.imgur.com/Qa541ae.jpg)
After some more wiring cleanup and future planning, it was time to test the cam/crank sensors and make sure the ECU was happy/synced. I took a log and trigger scope while cranking with no fuel/spark.
![](https://i.imgur.com/XaaK3f1.png)
SUCCESS!! ECU saw the cam/crank, and had sync. That concluded the night, and today/tomorrow I hope to have the engine started. I say that because the exhaust is still off, some more wiring to do, and the O2 sensor is unplugged. I also saw no oil pressure while cranking yesterday. I hope it just needs more time to prime as it is a fully empty pump and all. Also, today is Tuesday and I want to hit the trails!
![](https://i.imgur.com/EF3qhWL.jpg)
#105
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Today was a good day. There was some fumbling with the throttle cable starting to fray and not knowing how to fix it. Luckily a friend came by with tools and showed me the way. The correct VVT connector also arrived and I made quick work of that.
![](https://i.imgur.com/OuZxFsX.jpg)
![](https://i.imgur.com/0IY8CGw.jpg)
![](https://i.imgur.com/MgcLLcJ.jpg)
![](https://i.imgur.com/yELLd2G.jpg)
Then after some wiring cleanup and a sensor checkup, I gave it fuel and it fired right up!![Party Kitty](https://www.miataturbo.net/images/smilies/birthday[1].gif)
It had a steady 1150RPM idle and great oil pressure, so called it a day and went to the local concert. Tomorrow I'll try to source some exhaust gaskets so I can drive it and start tuning until the racing beat gaskets arrive on Monday. There is still more work to do, but this feels like a huge milestone.
![](https://i.imgur.com/tE0GwZL.jpg)
![](https://i.imgur.com/OuZxFsX.jpg)
![](https://i.imgur.com/0IY8CGw.jpg)
![](https://i.imgur.com/MgcLLcJ.jpg)
![](https://i.imgur.com/yELLd2G.jpg)
Then after some wiring cleanup and a sensor checkup, I gave it fuel and it fired right up!
![Party Kitty](https://www.miataturbo.net/images/smilies/birthday[1].gif)
It had a steady 1150RPM idle and great oil pressure, so called it a day and went to the local concert. Tomorrow I'll try to source some exhaust gaskets so I can drive it and start tuning until the racing beat gaskets arrive on Monday. There is still more work to do, but this feels like a huge milestone.
![](https://i.imgur.com/tE0GwZL.jpg)
#109
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Time for an update!
I got to work on the car for a good chunk of time during the work week. I didn't take many pictures but I'll do my best to detail what went down.
I got the exhaust gaskets on Monday and got that sorted. I went ahead and calibrated the VVT system, and immediately the car started idling weird. Noticed something was pulling a lot of fuel intermittently. Long story short, the EVAP setup was messing the tune because I left the purge valve unplugged and the ECU's short circuit detection freaked out. Tried disabling the pin but somehow ended up corrupting the map and had to reload the firmware to get the fueling under control. But that was about the only issue that day.
Then got to install these R Theory saw bar mount reinforcements
![](https://imgur.com/7ys974M.jpg)
![](https://imgur.com/HQNpx3E.jpg)
![](https://imgur.com/gew2DNm.jpg)
and last but not least, I was finally able to install the front brace of the FM butterfly brace again! The OEM NB2 header was hitting this brace before, but the racing beat clears it no problem. Sorry, didn't take any pics of this but I will when I do the next bolt check!
Fast forward to today, and I finally had time to take the car for a spin around the block! Right away the clutch pedal needed adjustment and that was easy enough.
![](https://imgur.com/PevBvJt.jpg)
![](https://imgur.com/Up62opw.jpg)
VVT hitting target like a champ!
Didn't get to do any real tuning today, and haven't even verified base-timing, but the car ran great, albeit rich. The last tasks today were to replace the clutch slave cylinder, reinstall the hood, and install some FM hood struts. Nothing too exciting I guess, but this means I'll be driving Scooter tomorrow and finally start tuning.
![](https://imgur.com/XbDIh3h.jpg)
![](https://imgur.com/C9N7Nh8.jpg)
I got to work on the car for a good chunk of time during the work week. I didn't take many pictures but I'll do my best to detail what went down.
I got the exhaust gaskets on Monday and got that sorted. I went ahead and calibrated the VVT system, and immediately the car started idling weird. Noticed something was pulling a lot of fuel intermittently. Long story short, the EVAP setup was messing the tune because I left the purge valve unplugged and the ECU's short circuit detection freaked out. Tried disabling the pin but somehow ended up corrupting the map and had to reload the firmware to get the fueling under control. But that was about the only issue that day.
Then got to install these R Theory saw bar mount reinforcements
![](https://imgur.com/7ys974M.jpg)
![](https://imgur.com/HQNpx3E.jpg)
![](https://imgur.com/gew2DNm.jpg)
and last but not least, I was finally able to install the front brace of the FM butterfly brace again! The OEM NB2 header was hitting this brace before, but the racing beat clears it no problem. Sorry, didn't take any pics of this but I will when I do the next bolt check!
Fast forward to today, and I finally had time to take the car for a spin around the block! Right away the clutch pedal needed adjustment and that was easy enough.
![](https://imgur.com/PevBvJt.jpg)
![](https://imgur.com/Up62opw.jpg)
VVT hitting target like a champ!
Didn't get to do any real tuning today, and haven't even verified base-timing, but the car ran great, albeit rich. The last tasks today were to replace the clutch slave cylinder, reinstall the hood, and install some FM hood struts. Nothing too exciting I guess, but this means I'll be driving Scooter tomorrow and finally start tuning.
![](https://imgur.com/XbDIh3h.jpg)
![](https://imgur.com/C9N7Nh8.jpg)
#112
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![Laugh](https://www.miataturbo.net/images/smilies/laugh.gif)
Hell yeah, brother! I’ll see you in Colorado!
![](https://www.miataturbo.net/images/smilies/beer.gif)
———
Some more detailed updates on the car this weekend:
got to drive about 60 miles only but that’s all it took the old engine to have a darker oil. This one is still clean. Feels good.
The street tune is almost done and I’m pleasantly surprised by how smooth and accurate the VVT is working. I thought I would notice the cam moving about but it just feels like the BP-4W. Power wise, meh, gotta dyno it because I can’t tell. I notice more poke in the lower RPMs, but could be mental. It isn’t night and day different. What I do notice is how quickly it revs in neutral and while downshifting. That lightweight flywheel and clutch setup is amazing!
There are two items that I’m struggling with: EVAP (again) and idle valve movement:
- The EVAP is climbing in pressure a bit, and the 4D fueling wasn’t responding as I hoped. After some testing I made the 4D fuel into a 3D table with tank pressure in the Y axis and that helped a lot, but the drivability was suffering. I hope to put some good miles and tuning time today to get it dialed, but like last time, I bet the root cause is an exhaust leak at the muffler. More info on this later when I have more to share.
- The idle valve used to sit around 22% DC for a 900RPM idle at 85C or so. But now that the operating temperature is higher, it seems to sit much lower, around 16%DC @93C. I’m not sure this is an issue, but I find that huge difference to be a little odd and wonder if the ITBs need to be rebalanced for this engine. I don’t think I’ll have time to do that before the trip but I can at least check for vacuum leaks. There is no oscillation, only higher RPM than target until the closed loop catches up.
Overall, given all the huge changes, I’m willing to call the weekend a success. I have to do another bolt/nut/leaks check today before I drive it, and then swap to track tires and get ready for the trip. So far it’s all working!
![cross your fingers](https://www.miataturbo.net/images/smilies/x.gif)
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