AlexL's 91 1.6 Greddy MS1 Build
 

Hi All,
My build is progressing and although I have everything ready to install it has been too cold to do it.

Over Christmas I purchased 92redturbomiata's old Greddy kit before he sold his car. My build will be identical to his except I think I'm going to use a different wideband, an old PLX M200 that doesn't require separate controller wiring from the gauge, it seems to be a lot easier to run than the LC1 that came in the "kit". I have been pestering Tadd with questions about the MS1 as I was pretty clueless before I spent lots of time reading old threads. I know the MS1 in parallel mode gets a lot of hate but it seems to work well for a lot of people too. Things I was confused about; Wiring the VTPS, wiring the IAT, wiring the fuel pump relay, using Tunerstudio (I upgraded to the full version). I have used lots of Honda ECU solutions in the past (Crome, Uberdata, Neptune) and they all seem to be a bit simpler than Tunerstudio. Hopefully I'll get over the learning curve once I get the car running. I'll try not to fry my ignitor.

My build includes:
Greddy Kit
Ebay intercooler
Rx7 460's
Really Old Brain MS1

I could probably finish this in a weekend if it was warm enough. I've been using a diesel space heater, which is nice and warm but also makes it hard to breathe.

Just finished putting my Torsen and clutch in a couple weeks ago:
https://www.miataturbo.net/attachmen...ine=1361459695

https://www.miataturbo.net/attachmen...ine=1361459695

My garage and the kit:
https://www.miataturbo.net/attachmen...ine=1361459695

https://www.miataturbo.net/attachmen...ine=1361459695

New Diff Bushings:
https://www.miataturbo.net/attachmen...ine=1361459695

https://www.miataturbo.net/attachmen...ine=1361459695

https://www.miataturbo.net/attachmen...ine=1361459695

ACT Clutch:
https://www.miataturbo.net/attachmen...ine=1361459695

Turbo Kitten:
https://www.miataturbo.net/attachmen...ine=1361459695


Lots more to come as the weather improves. I'll also use this thread to ask stupid MegaSquirt questions should they come up but hopefully I'll keep that to a minimum. :cool:

How did this work?
https://www.miataturbo.net/attachmen...ine=1361459695

I have no idea how to get the rubber off mine.

Put them on the grill on med-high until it gets nice and smokey, then hold the metal with a gloved hand and pull the rubber off with pliers. Took me 10 minutes. What the heat from the grill does is melt the glue that holds the rubber onto the metal, rather than actually melting the rubber.

VTPS and Harness

https://www.miataturbo.net/attachmen...ine=1361538694

MS1

https://www.miataturbo.net/attachmen...ine=1361538694

Aux fuse box

https://www.miataturbo.net/attachmen...ine=1361538694

hey that stuff looks oddly familiar. good call on upgrading those bushings, im sure they were warn out. where did you pick up that fuse panel, i might pick one up for my build.

I got it at Summit. I think it was $70. I wanted to properly add circuits to the car for gauges, MS, o2 sensor, whatever. I've been half-assing wiring in my cars since I was 16 so it was time to do it right.

Tadd, while you're "here", can you confirm these pictures? I guess I'm still not sure on the cut pink wire.

https://www.miataturbo.net/attachmen...ine=1361550832

https://www.miataturbo.net/attachmen...ine=1361550832

While we're on the subject of doing wiring the right way, friends don't let friends use vampire taps.

Since my wiring is totally untouched at this point it has the potential for cleanup, and being done correctly. :)

cause you dont have the center connector apparently.

Not sure what the center connector would look like. I have this:

https://www.miataturbo.net/attachmen...ine=1361557607

it would fit into the middle of the yellow connector so you can wire to that the wires that were cut off.

This guy?
https://www.miataturbo.net/attachmen...ine=1361559087

It sounds important. I was planning on just removing the cut wires and running new ones to those pins.

if you dont have that, just wire directly to the cut wires.

center connector was missing when i got it, and i did the wiring the quick and dirty way. i would recommend doing it correctly

The best thing about the 90-93 chassis is, you don't care when you wreck the paint.

https://www.miataturbo.net/attachmen...ine=1361662581

Aftermarket fender was literally "screwed" onto the bumper. Thanks a lot previous owner.

https://www.miataturbo.net/attachmen...ine=1361662581

The carfax said it was in a low speed front collision. The tweaked chassis, dent in the subframe, and aftermarket front pieces indicate otherwise.

https://www.miataturbo.net/attachmen...ine=1361662581

Gosh that greddy turbo is tiny, and it still manages to spool slow.

https://www.miataturbo.net/attachmen...ine=1361662581

Yeah but it makes up for the lack of low-end with a lack of top end.

Posted my question in the MS forum.

someone's been listening :)

Yeah I got some good lols out of that one Brain.

Reminded me of one my neighbor who was a recording engineer told me: No highs, no lows, must be a Bose.

looked at your ms thread, what brain told me to do, i also unplugged the fuse.

That's not a method I ever recommend anymore.

There's still no need to pull the fuse unless you have a MSPNP or your MS was built using a high-side driver circuit like the MSPNP.

I don't build that and my solution requires the user to jump two pins in the AFM connector. the end.

I at least found the fuel pump wire on pin 37. It's gray and it runs to the black wire, not the long white wire as previously thought (I think my long white wire runs to pin 29 which is fans?).

Pink still looks to be wbO2 which is on Pin 23. This goes directly to the db37 connector because the stock ecu doesn't know to expect a wideband o2 signal, right? And then I run my narrowband output from my wideband to the short white wire spliced in my harness I guess.

Although I don't see a spot for the oem o2 signal in here:
https://www.miataturbo.net/attachmen...ine=1361889806

Ok so I opened up my db37 connector and just when I thought I was understanding things I am confused again. I know the position is important, not the color. Since the diagrams for the db37 only have color it is hard to trace them back to my incorrectly colored harness. So I'm looking for 5VREF since the blue TPS wire on pin 22 looks correct, apparently spliced into the harness to accept the signal from the stock TPS. The 5VREF wire on pin 26 which is supposed to be gray is green, and it's labeled F-Idle, and it's spliced into the stock harness (why?) since I don't know what the stock ECU is going to do with a variable TPS signal. Seems like I should just cut that wire too. Maybe this will make more sense when I look at my oem wiring.

https://www.miataturbo.net/attachmen...ine=1361889806

https://www.miataturbo.net/attachmen...ine=1361889806

Your MS was on a piggyback harness where the user wanted to keep the AFM, so it probably never had the fuel pump wire installed. There was no point. It was probably installed later, it should have been purple.


Correct, pink is on pin 23 which is the O2 input. However, I DO see OEM NB (narrowband) on the chart above, which is on pin 2N. Your MS can only take in 1 input, so you want to hook your WBo2 into that pink wire, which is why it's not in the harness.

it's possible this unit was prewired for a vTPS (not sure why the green wire). Otherwise the stock TPS is unusable. You need to figure out exactly where the Blue wire and Green wire go on the harness. If the green wire goes to pin 1N, then you must unplug the stock TPS connector until you upgrade to a vTPS, else it will cause a fault and the MS will not connect/run.

The unit doesnt have the idle control wire attached on pin 30 because, again, the unit was built for a piggyback setup and therefore the stock ECU controlled the idle.

If you want to run the fuel pump, connect the wire on pin37 to 2O. then jump the two pins in the AFM connector.





Please stop referencing old-outdated, bad-practices, charts/info and just ask here. A lot of MSI information out there should be purged in a great big bonfire. Also please stop circle random colored wires and spots on the harness. I need exact positions to help you out. (e.g. Pin37 is unattached, but pin 36 goes to 1H.)

Trying not to, it's hard to tell what is relevant anymore.

This.

Thanks, I really do appreciate it. Sorry for trying to MS Paint the questions here. Brain, would it be possible to build a fresh db37 and harness for me? Can I PM you about such a service? I'm almost ready to just get an MS3, almost.

I hate building harnesses. yours is fine, you just have some loose ends to fix from 2007. :)

I have a VTPS. If the pin 26 green wire goes to 1N then it is receiving the 5VREF from my VTPS that I will be splicing into my stock wiring at the connector in the engine bay. So that should be correct?

Yes, that is the plan. Am I splicing into the wire on position 20 or am I cutting it before it gets to the ECU? And for my sanity, this is Position 20 right? It was hard to read until I zoomed.
https://www.miataturbo.net/attachmen...ine=1361896671

Ok I'll take another look tonight

correct.


yes you'd want to cut the wire back to the stock ECU (are you even going to use the stock ECU?) because that's normally the 5v output from the ECU to power the AFM.


do you understand what that means? the wire should go from the MS to the oem wiring, but not be touched by the oem ECU, so the red wire in the harness connecting those should be severed. you'll see this on pins 2U and 2V for example.

Just planning to use the stock ECU for idle and codes. Ok I'll cut that wire and jump it at the AFM like you said. My brain hurts but this is all starting to make sense.

My brain always hurts too.

Yes, wire will go from yellow connector back to db37. Never goes to the plugs that send everything else back to the ecu. It's funny that there are so many wires going back to the ecu but it's doing almost nothing.

you could remove the majority of them and still keep the ECU from tossing codes, yes.

Almost done with the harness. One more vampire tap to remove. This finally clicked for me last night.

https://www.miataturbo.net/attachmen...ine=1361996996

Made some progress despite it being 36 degrees in my garage.

Turbo and downpipe Mounted:
https://www.miataturbo.net/attachmen...ine=1363707513

Oil pan drilled and tapped:
https://www.miataturbo.net/attachmen...ine=1363707513

JB Weld:
https://www.miataturbo.net/attachmen...ine=1363707513

The intercooler bolted here perfectly but of course the bumper won't fit. I think I may move it closer to the radiator and do some duct work.
https://www.miataturbo.net/attachmen...ine=1363707513

Intercooler is in, piping being routed. Going to get tight around the PS pump.

https://www.miataturbo.net/attachmen...ine=1364303727

https://www.miataturbo.net/attachmen...ine=1364303727

Piping done:
https://www.miataturbo.net/attachmen...ine=1366122230

The Cluster F that is my wiring right now. Have to trim my boost gauge line so I'm not just shoving it under the dash.
https://www.miataturbo.net/attachmen...ine=1366122230

My Boost gauge is kind of haphazardly in the eyeball vent, have to get some better fitment. Things left to do: Bleed my clutch, plug in the MS, and clean up some wiring. Then I'll be ready to start the car.

It's alive!
 

Did this on Thursday:
https://www.miataturbo.net/attachmen...ine=1366375301

Then last night I calibrated my TPS, which of course was wired backwards. Primed the engine with cranking. Flashed the firmware with my ignitor unplugged. Pulled the tune from the MS and started her up! Click for video.
http://img.photobucket.com/albums/v7...psc20ab029.jpg

I still need to wire in some capacitors for the narrowband output to the stock ECU and the wideband output to the MS but otherwise it seems to be running pretty decent. I'm using an 8 year old PLX M300 because it's simple and combines the controller and gauge into one piece. The car is still on stands but hopefully this weekend I can start tuning. :party:

Ok I finally got out to do some tuning today. I set the timing which made the idle nice and smooth and went for a cruise.

At first with the map that was loaded from the previous owner (92Redturbomiata) the car was running great, 14:1 AFRs in cruise, nice and rich in boost (11's right now). I did some auto-tuning, everything is fine. Then I pull over to check my oil lines (the Greddy turbo is still giving me wisps of smoke despite a nice and big and direct return line). When I started the car back up it was running super lean. Like 17's in cruise, 14's in boost.

I'm only going to 1-2 psi right now since I'm paranoid. Then the car is barely idling at like 18:1. So I bring the car home, adjust the idle by hand a little, then take the car out for an auto-tune. It immediately starts richening up my whole table because the car was running super lean. Now it's running better but I'm wondering why all of a sudden my whole fuel map is lean. In a bizarre coincidence my check engine light which was on (I thought was for the narrowband o2 signal even though that is hooked up, but I never pulled the code since the ECU is doing almost nothing) is now off.

I've attached a log and my tune, which was my first time so I hope I did it right. Maybe my stock fuel pump is giving up or something? Oh well, no harm but I'm just a little concerned, and confused. Thanks for the help! :noob:

if it was giving you burst of smoke it might have caught some on the o2, might clean it and try again. thats weird that its smoking a bit, i never had a problem from it even with it draining to the passenger side nipple. ill look at the MSQ and Log later to see if i noticed anything.

It's not smoking a lot. I have a wicked exhaust leak where my cat gasket cracked. If you stare at the downpipe you can just see, and smell, a hint of smoke when it's idling. I swapped the return line twice I was so paranoid but the current line is 3/4" and straight down. If the turbo is smoking at this point, it has to be the turbo seals. I also smell oil burning when I rev the car up and hit just a little boost. I'm running dino oil right now to clean out the shavings from drilling the pan. I plan on dumping the oil soon, so we'll see.

I'm more confused about why my whole fuel map is lean now. Unfortunately I only get to drive the car on the weekends as I don't feel comfortable commuting in traffic with it yet. It's a shame too because when I first took it out it was idling great and boosting nice and safely.

Can't quit smoking
 

So the turbo is still smoking. The car is running great thanks to auto-tune but I cannot figure out my smoke issues.

I replaced the oil drain, oil drain flange, oil feed, oil feed fitting, and still the center section of the turbo just looks wet. You can smell it and you can see the smoke if you stare at it. I replaced the oil drain flange gasket because I thought that was trickling oil out onto the center section and causing it to smoke, and it seems better, but it's still smoking.

I know the only reasons for smoke could be too much oil pressure (which I thought was unlikely with the Greddy turbo), a backed up oil return (I've replaced it three times, it is fat and wide open), or bad turbo seals. It almost looks as though oil is just seaping out of the seals and "burning" off on the center section. No oil in the exhaust, no oil in my IC pipes, no smoke coming out of the exhaust, just under the hood.

Here is a video where you can see how the center section just looks wet. Next I'm going to try putting a really small turbo feed fitting on top of the turbo to cut down on the pressure, but I'm just concerned about starving the turbo for oil...

https://www.miataturbo.net/attachmen...ine=1368536332

did you use cooper crush washers on the oil feed?

Yep. I have literally put my face within inches of the oil feed and stared at it. I swear it's not leaking. I'm using the original oil feed banjo bolt to hold the new fitting that came with the eBay oil feed kit. The banjo bolt that came with the kit has a ridiculously small oil hole that I was hesitant to use.

I guess I'll try new crush washers before switching the banjo bolt.