I am sure this has been asked before because there are no new questions under the sun for 20 year old cars. I will continue to look. I am looking at the FM stage 1 since it seems to retain legal emissions. In a couple years my car will no longer require emissions due to aging out and was wondering what the process to convert to a stand alone at that time would look like and if it would see substantial gains to do so. I am not looking for a lot of peak power(vague I know) I want a to create a low boost threshold with a usable mid range. If anyone has a kit setup they recommend to achieve that I am glad to take any advice.

 

What year is the car? If mismatched, what years are the body and the engine?

Is this a US-spec car?

 

Doh, helpful info would be helpful wouldn't it.

Its a 2002 SE. US car all matched parts. About 140k miles on it. It has had belts and water pumps replaced at 117k. Its getting a cross flow radiator and a reroute right now.

 

Ok.

So, I'm gonna start this with a disclaimer: While I've turboed a few cars over the years, and have installed many aftermerket ECUs, I've been driving a bone-stock '04 for the past seven years. So I'm not guaranteed to be up to date on the latest and greatest.

The Megasquirt 3 is by far the most capable solution for a late-model NB. These days, plug-n-play versions are available. I'm only now looking at the DIYAutoTune website for the first time in years, and damn, the prices have really gone up, but this would be an excellent starting point: https://www.diyautotune.com/product/...-manual-trans/

That right there will deal with all of the "fancy" stuff on your engine. VVT, alternator control, and... Ok, I guess a 19 year old Mazda doesn't have all that much fancy stuff by modern standards.

Point is that it's a no-brainer starting point.

Add a wideband O2 sensor and a set of fuel injectors rated for maybe 600-1000cc/min. Ask around, and you'll get different opinions as to which ones are the best. I've been out of that game for long enough that I'm not gonna pretend to know what's best these days. The last time I did one of these engines, the best wideband sensor was the Innovate LC-2, and one of a number of companies which various people claimed to offer the "best" injectors in this class was Deatschwerks. Links to both below, with the expectation that someone with more recent experience may have better insight.

https://www.innovatemotorsports.com/products/lc2.php

https://deatschwerks.com/collections.../18u-05-1000-4


Honestly, it's a hell of a lot easier to build up a standalone system like this if you start with a baseline stock engine, from a tuning perspective. Less risk of blowing it up. Not sure what state you live in, but when's the last date you'll need to do an OBD-II exam?

 

I'd SAVE everything I took off the car.
I'd label, clean, and store the removed stuff somewhere safe.
I'd take pictures, make diagrams, do whatever needed to be done to make it easy to restore to stock.
I'd leave the original wiring harness alone and add wiring as needed for my mods. Repurposing existing wiring is fine but you should T into the circuit instead of cutting the original end off of it.
On that late a car the ECU and the security system are paired. The original ECU is the ONLY plug and play stock ECU you can install back into the car.

This will give you the option to return to stock down the road.
The emission critters are constantly trying to make the laws more stringent.
The last go around they wanted to enforce "all emissions controls present on anything that has a VIN."
This included fully prepared trailer only race cars that will never be driven on a public road again.
They were unsuccessful.
They will be back ..

It will also give you the option of returning to stock to sell the vehicle should that become necessary in the future.
Just being able to say "I have everything to return this to stock" to a potential buyer is valuable and it allows you to sell the turbo system separately from the car should you wish too.

Tell us where you live, this may change our responses. California is far more stringent than Texas and in Texas certain counties are far more stringent than others. I moved from a stringent one to a much less stringent one...
All I have to pass (even on a brand new car) is a visual test.
"Is the cat and all the o2 sensors, EGR, Evap system on the car?" is all I have to hit. They do not test to see if the stuff actually works, they do NOT plug into the OBD2 port.
It is possible that this might change in the future, so I save all my original crap anyway.

I am also in agreement with Joe
Figure the MS3 out on the stock engine before adding boost.
This doesn't mean get the car running and add boost the next week.
This means get the car running and play with the MS3 until YOU are trained properly, this might take weeks, months.

If this is too much you will need to find a tuner in your area that works with the unit you have chosen.
Some folks are good enough to do this stuff remotely. There are people on this forum that can do this.

My suggestion for a simple effective "kit" is the MKturbo stuff.
MK Turbo - Make your miata go from Meow to RAWR!

He is a forum member, he stands behind his products and his stuff is pretty nice!
His system will exceed your goals in its smallest configuration.

His stuff can handle FAR more power should that become necessary.
/www.miataturbo.net/build-threads-57/sonofthehill-sets-his-sights-mk-ultra-85108/
http://www.miataturbo.net/dynos-time...on-hill-87318/
Sub 12 second 1/4 mile on all season tires is actually possible with the MKturbo kit.

 

You guys have been awesome, I'm in Georgia. In the metro its OBII and all on the computer to determine. They check the dash for lights. I can register the car outside the metro easily enough.

 

So... wait.

As a person who hasn't lived in Georgia since 1977 (I was born there, didn't stay long), I'm reading this as two completely opposite statements.

One is that they do a plug-in OBD-II test. The other is that they just look at the CEL on the dashboard.


OBD-II plugin is seriously hard to reproduce with aftermarket hardware. "CEL lights up at startup, and then goes off" is trivially easy.

Which is one is Georgia doing these days?

 

Sorry for the confusion, they check the CEL as a visual/ non starter if you fail then run an OB-2 scan where the computer gets scanned.

 

That also doesn't seem clear.

Taken for how it's written one would think they don't plug in to it unless there is a check engine light issue. If that is actually the case it's incredibly easy to work around.

 

If you can register the car outside the metro Atlanta then do so. There is no emission test. Inside the metro area the car has to be 25 years old to avoid the emission test. OBDII test gets connected to the computer.

 

I'm in ATL (came here from DTW where they don't give a damn about emissions - go figure) and I've turboed my car. Every year I go through the same ritual to get it "legal" again;
- Disconnect and wire open the WG
- Replace the WBO2 sensor with a NBO2 (the second NB sensor "lives" under the driver's seat and that bung is plugged until time for testing)
- Replace the injectors w/ stock purple-tops
- Re-connect the vac lines for the stock MAP sensor
- Replace the exhintake cam with the stock cam
- Disconnect the MS and plug in the stock ECM
- Plug a bluetooth OBD module into the OBD port and fire up Torque on the tablet
- Fight with the ECM to figure out this year's OBD codes that get set
- Run the Mazda drive-cycle until the monitors are set (can take as long as a week, or as short as an hour - don't know why the variation)
- Creep to a testing station to avoid any unwanted codes
- Pass the test
- Reverse all of the above and go have some fun

Yes, it's a PITA but 2 hours of wrenching and a week of frustration is well worth the effort. I'm 2 years away from ageing-out. I can last that long.

PS - I have no intention of "returning it to stock" 'cause I'm never selling my car.

PPS - Yes, GA checks to make sure that the dash lights come on and then go out. Not doing so is a "fail" (regardless if you have codes, or not). They also read the ECM for any codes current, or past - any code, no matter how trivial, is a "fail". Any "drive monitor" that is not green is an "incomplete" (for my year - 99 - you can have up to 2 monitors not set green). Ask me how I know.

 

So, I want to be sure I understand correctly:

If the CEL illuminates at key-on, and then goes out a few seconds after the engine is started, then they do NOT bother with the plug-in test?

That's hard for me to believe, however programing the CEL to behave in this way with an aftermarket ECU is not difficult.

 

Aktcually, MS3 can't CEL like that.

The stock ECU keeps the CEL till the engine is started, then stays a few seconds after. MS3 doesn't do that with the CEL configured as a CEL, You'd have to program it as a digital output, probably with a lot of loops for multiple activation/deactivations.

There's no "timer since engine actually running", so getting it to turn off after the engine starts is gonna take something else to trigger, like a RPM crossing point. Maybe there's an engine revs counter? I don't know, but I know there's no engine running timer.

 

Just guessing but if they're just cycling to KOEO and watching the bulb test and then confirming the bulb turns off with the engine running all you need is a cheap timer relay.

 

The CEL functional test is being misconstrued. Almost every emissions place I know does this prior to plugging in just to verify the CEL is working. If it's not, then while it's not an automatic fail, it's a "yeah this broken and before we charge you $10 and start the clock on the 30 day free retest, this needs to be fixed."

Still need to pass 4/5 readiness monitors (3/5 if the car model is < 00 iirc).

https://www.cleanairforce.com/wp-con...ness_FINAL.pdf

 

Gooflophaze is exactly right, I'm just going to try getting registered outside the metro based on Rwyatt's response.

 

I went with the mkturbo kit. For the easiest pnp

 

Honestly, I would go with an NC and have the stock ECU re-flashed after adding any power adders. The MS3 I have is very capable, however, I have at least a hundred hours into tuning it and in hindsight, I would not have gone with a standalone for my street driven car.

I am in NH, and my 2000 is grandfathered so that any issues with the OBD II system does not need to be repaired. My mechanic usually states that "there is not signal at the OBD II port" and offers to diagnose if I choose. My mods are so far past putting a stock ECU back into the car, I'd likely just sell it for track duty before I put any of the stock emissions/MAF stuff back in.

 

Everyone has their own "breaking point" - mine, it appears, is quite a bit higher.

When I started down this path 20+ years ago I never thought I would get in this deep, but I'm glad I am. I can't conceive of selling my car and I couldn't recoup 1/10 of what I've put into it (not to mention the hours spent - some number of thousands, I'd guess). This has ceased to be a "rational/financial decision" on my part and has long ago lapsed into an obsession. Now that I can claim a "senior exemption" from any GA emissions testing I'm a happy(er) camper.