Tuning the Megasquirt (Pt 8.) - Electronic Boost Control

We had previously dived into Manual Boost Control which is an easy way to up your boost and avoid boost sag ( • Control Boost for Chea... ), but now we'll get into the wonders and flexibility of Electronic Boost Control (EBC). In this episode we will explain everything you need to know and how to install it in the car and test it using TunerStudio before you even start the engine.
Supplies:
MAC Solenoid (be careful there are many fakes!) - amzn.to/3tbuEcI
1/4" npt hose barbs - amzn.to/3j2Tyqa
1/4" npt muffler - amzn.to/3iZTk2W
7/32" vacuum hose - amzn.to/36mf8AT
I bought this separately to save a little money (my price was $40 total) but there are also some kits available for about $15 - 20 more.
You might also need some 22gauge AWG wire (the solenoid comes with about a foot). I made mine plug and play by crimping some small spade connectors to the ends to plug into the stock MAF harness as shown in the video. On a 1990 - 2005 Miata this is super easy but basically you need to get one wire to +12V and the other back to your Boost control output pin in your Megasquirt or other ECU.
#namiata #boostcontrol #tuning #megasquirt
OGPedxing is all about DIY, gadgets, and tools.
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[@1knowsnothing1]

Thanks for providing such valuable content and giving back to the community. I always learn something.

[@rick01jetta]

Awesome! I've been waiting for a vid like this! Your turbo setup looks almost identical to mine!

[@Lovely_planet]

Thanks man. After a year of my boost controller sitting in a box, it’s finally time to install it. I tired watching so many videos to understand it and only After I installed my diverter valve did the turbo no longer scare me and I am grateful for your explanation !

[@jimmy2002ful]

Thanks for taking the time to do this 😊

[@audirx8]

Great video. I was planning on using #2 port for my vent but after your explanation on port #1 being normally closed It makes sense to use 1 as vent

[@eottracingteam8274]

Awesome 👏 video bro, this has definitely helped me out.

[@him4201]

Great info even better video good job 👍

[@dashobie]

Great explaination Thank you.

[@5PointSlow]

Ty for the info very much appreciated

[@pedroramos3740]

Super helpful 👌👍🏽👏

[@MrIntercoolers]

Great help thanks.

[@flux_core_fx]

Thank you for the very informative vjdeo! Also, your voice reminds me of the Regular Cars guy haha. Subscribed!

[@OGPedXing]

Lol, nice 👍

[@flux_core_fx]

@@OGPedXing do know if you need the mod kit for MS3x? Or can it drive a solenoid directly? Thank you again! Great video

[@OGPedXing]

Yep it will drive it directly. This is a nice benefit of the ms3x, mod kits are mostly a thing of the past, all the nice features are built in.

[@flux_core_fx]

@@OGPedXing that is awesome, thank you

[@OGPedXing]

No problem at all, good luck with your build!

[@nabilriahi4019]

Thanks well explained

[@learysinsight9617]

I had a manual on my BuickGN, I couldn't tune it properly. so now I'm going to the solenoid. I wish I would've done that from the start.

[@LMLracing]

Thank u

[@kevinsaeed9817]

Thank you for posting this video. Very detailed and thoughtfully put together. On my MS3PNP PRO I am not able to use the MAF harness for the signal wire, I need to wire into the options port on the ECU. Do you think I can source the 12V from the MAF harness like in the trubokitty diagram you posted and run the signal wire to the ECU?

[@OGPedXing]

Yes, that should work fine.

[@kevinsaeed9817]

@@OGPedXing thank you. The wiring diagram for the 94-97 shows a red wire and green wire going into the MAF from the EBC. Which one would you use for 12V switched (1B red / 2O green)?

[@OGPedXing]

@@kevinsaeed9817 the 1b red should be 12v and the 20 should be the signal which is a switched ground from the regular ECU.

[@kevinsaeed9817]

@@OGPedXing awesome, thanks for your help. You gave me the confidence to buy an EBC and try the installation. Thank you.

[@OGPedXing]

Glad to help! You can also test 1b with a volt meter to make sure but the solenoid itself doesn't have polarity.

[@DJimeku]

I have my boost solenoid installed to a 12v switch. When I give it power, it flickers right away (audible). Do you know why this is? I thought polarity of the wire didn't matter?

[@validonsummer1453]

Having issues connecting to my ecu after this, running ms2pnp w/extra. Checked baud rate, but just throws a bunch of failed connection attempts. Any ideas?

[@kevinsaeed9817]

I ordered an EBC from DiyAutotune and it came with plastic fittings and they look to be for an 1/8" ID vacuum hose which is smaller than the hose I'm currently running from boost reference to wastegate. What OD/ID vacuum hose and barb fitting are you using?

[@OGPedXing]

Yeah I'm using 1/4 inch on the hose side. I think the ebc side is 1/8 npt. I used these amzn.to/36ToFSX

[@kevinsaeed9817]

@@OGPedXing thank you, order placed. Going through your boost tuning videos now while I wait on Amazon. Thanks for all you do!

[@davidfernandez01]

Hello! Do you know if it will work with a diesel VNT/VGT turbo? Want to replace a tillix and needle valve to avoid over boosting on a nissan patrol y61 zd30. Thanks!

[@davidfernandez01]

By the way... it is vacuum turbo

[@OGPedXing]

Normally this valve is used for pressure wastegate actuators as opposed to vacuum. I've never seen it used for that but it might be possible. The specs for the valve say the pressure range is down to vacuum. Here's some more info: www.macvalves.com/wp-content/uploads/PDFs/Series_Pages/Sm3ways/35catalog.pdf

[@KubieSnacksz]

what pin did u use on the patch harness(side that connects to stock harness) for the boost, so it reads it from the MAF plug?

[@OGPedXing]

On the megasquirt side I used pin X-6 (expander board pin 6) to connect to pin 2O on the oem harness side. This is the pin that's normally mapped to "boost" in tuner studio and 2O is the maf wire.

[@KubieSnacksz]

@@OGPedXing but arnt you suppose to use pin 2O for the new AIT sesnor that plugs into the maf Sensor stock conocter?

[@OGPedXing]

@Kuba Podgorski I'm using 2P for that one but you can swap them. Since there's no maf they are just wires to the maf connector so you can have them go to whichever megasquirt pin you need. Edit: I have a 94, the wiring varies a bit with the year.

[@KubieSnacksz]

@@OGPedXing so basically the stock maf connector pins get split into two different signals when it goes into megasquirt? i have a 95 and 94-95 have the same wiring for the patch harness on turbokitty.net. So technically I can follow your setup using the stock MAF harness to plug in my AIT and boost leads into the corresponding leads on the stock maf connector? Also thank you for responding i really appreciate it.

[@OGPedXing]

@@KubieSnacksz yes,that should work!

[@AngelRodriguez-kp7ug]

I had a megasquirt 2 and said I the back that I need to use the JS11 pin on the relay board for my boost controller. What I need to do. Connect on cable to JS11 and the other one to 12 volt source. Or how you do it.

[@OGPedXing]

Yes that should work. Basically js11 needs to be a ground signal in that scenario. If that doesn't work then js11 may be normally 12v so you'd need to connect the other side of the boost valve to a ground. Either way can be experimented with and it won't damage the valve.

[@frankdeninno7182]

What an i doing wrong. I can control mac valve from Output test but it wont control from tps i set it to ramp from 10 to 100 it follows the tps on the boost duty cart but wont contol the mac valve it just stays open limiting boost to 7 psi no mater how much duty i throw at the table os t

[@AdamOpheim]

IS there a way to change KPA to PSIG on the MS3 platform in tuner studio? -thks!

[@OGPedXing]

No, afraid not. If you want to mess with the ini files you can potentially use PSIA (absolute). But not psig. Kpa is easy to convert back and forth...0 is -14.7 psig and 100 is 0 psig, etc.

[@AdamOpheim]

@@OGPedXing I have the conversion chart on the desk top. Just a pain to go back and fourth when your dealing with changes that aren't in simple 100kpa ranges. Have a drag car that runs upwards of 30lbs and runs a boost ramp. Always having to jump back and fourth is a pain! -thks for the reply!

[@KIOGORANICK]

Hey, I have mine set up today with port 1 from turbo pressure source and port 3 as vent to atmosphere. Does that affect it's functioning?

[@OGPedXing]

There are different models with different port set up...the important thing is to be sure that if the solenoid is not working (no power) that your turbo gets the full pressure from the source. You can test this by just blowing through the ports with nothing connected and then trying it again with a constant voltage applied.

[@KIOGORANICK]

@@OGPedXing thank you so much for the information. Mine is the exact same one as you're using in the video. I'll test and rectify the setup appropriately.

[@KIOGORANICK]

@@OGPedXing I've checked and done the piping exactly as you have demonstrated. It's working perfectly now. Thank you so much

[@jacksonhamblin5242]

Do you by chance know if you can use the MAF the same way you did with the IAT and EBC with a MS3ProPNP?

[@OGPedXing]

You mean the maf plug? Yes it should work, what year is your Miata?

[@jacksonhamblin5242]

@@OGPedXing yes, the plug, sorry. My Miata is 1995. But, it is the 1995.5 with the tach signal being send from the ECU rather than the coils.

[@OGPedXing]

@@jacksonhamblin5242 yep, that will work. Your 1995.5 has the same maf plug as my 94 so it should be the same as shown in the video. Here's the link to the wiring diagram trubokitty.com/#/installation. Scroll down to see the maf and iat setup. For your ms, you will just need to set the right output in tuner studio. Usually this is labeled the boost or maf output. Worst case, you can use any avaliable output on the ms and connect to either lead on the ebc with your own wire. Then the other lead can go to any nearby 12 volt source.

[@jacksonhamblin5242]

@@OGPedXing thank you for the resources and help. I have another thing that I cannot find a completely clear answer to anywhere, with the 95.5 tach being ecu and not coil driven, do you know if is this a setting under tacho output inside the ms3pro/tuner studio that can be changed between ecu/coil or is this purely a chassis wiring issue?

[@OGPedXing]

Should just be wiring, you can check the 2I pin on your ecu connector plug and make sure it's not empty in the car wiring. It shouldn't be if it's a 1995.5. The ms3pnp should output the tach signal there automatically. Usually it's the 94 guys that have problems with a dead tach because it's expecting it from the coil not the ecu in the dash cluster. But either way, you can also configure an output on the ms and wire your own line to the tach/cluster. Unfortunately I don't know the pin for the tach signal at the cluster side.

[@rick01jetta]

Do you know what boost control pin I use to wire this to a MSPNP2 on my 94'? Also can I use the two pins on the on the MAF plug like you showed without having to run new wires to ECU?

[@OGPedXing]

Double check the pinout for your ECU here: www.megasquirtpnp.com/docs/mspnp_g2_genInstall.php?boardVer=13&isModel=2 but I think it is on the Options plug rather than the plug and play harness. It'll be pin 7 on the options plug. However you (with a 94 Miata) can tap into the wire to 2O on the stock harness and jumper that to pin 7 on the options plug so you don't have to pull another wire through the firewall. If pulling the extra wire is no big deal then that becomes the signal wire (signal ground) and then you need a 12v from that blue plug I show or I think the first pin of the maf connector (you can confirm with a voltmeter when the key is on). Let me know if that makes sense or not.

[@DarkDMD]

hey man - if I wired into my Miata's MAF wires, what is the output setting for the boost control?

[@OGPedXing]

Most miata specific tune files have it already set up to be the "Boost" option on the output drop down.

[@DarkDMD]

@@OGPedXing I dont know why, but I think through updates, its now called High Power 2. I ended up using the 12v from the MAF red/white and then just running my own cable to the rear options connection port R

[@DarkDMD]

@@OGPedXing Oh I meant to ask, does the 9V test when this is used for a dual port external wastegate?

[@mastermoarman]

I wonder if a 2 port version could be used as a iac valve

[@OGPedXing]

That should work, the only issue would be the housing. It need to input air to the other side of the butterfly valve in the throttle body. So if you had a tb without an IAC then you could drill into it.

[@mastermoarman]

@@OGPedXing ya I'm rewiring my 2008 rzr 800 with a microsquirt. Also replacing factory throttle body with a bigger one so there's allready going to be allot of custom parts. I wonder if a actual 2 wire iac would be as loud as that thing is lol

[@boiled4safety]

For the boost signal wire and 12v wiring on your maf plug How does the megasquirt know that the maf wiring is now for boost control Do you snip the wiring on the ecu side to reroute to boost options wire?

[@OGPedXing]

The maf is unused by the megasquirt, it uses a map sensor instead. So conveniently, the maf wire plus a nearby power wire can be reused for the boost controller. Most of the miata tune files have this pin on the factory car harness pre mapped to be called "boost" so usually nothing needs to be changed in the wiring or in the software.

[@liammoore8287]

@@OGPedXing hey, so I'm having the same issue understanding what pin to select and how to figure it out. On the NB1 I was told to connect my solenoid to the factory purge valve as it has 12v power and a signal to the ECU. But I have no idea what pin to select on the boost menu and literally no one says anything about it on the forms. so I'm just confused in general.

[@OGPedXing]

For the nb1 it's similar. You have a 3 pin ait plug for the air intake temp sensor. You can use the right two pins for the boost solenoid, polarity doesn't matter. This links to pin 2L on the main ecu harness. The other is ground. You can test that this is correct by using a multimeter set to ohms or continuity setting and getting a connection from 2L to one of the pins on the ait plug. A wiring diagram I have labels from left to right the pins as 4a, 4x, and 4af. You want 4x and 4af.

[@liammoore8287]

@@OGPedXing Thank you for the fast reply I really appreciate it. I hooked up my GM AIT sensor to what I assumed was the factory plug with 2 wires (that's near the MAF sensor plug.) So I don't believe the factory AIT sensor has 3 wires? Right now I have my boost solenoid connected to the factory purge valve also called the evap solenoid. Could I possibly get a link to this wiring diagram? I defiantly need to do more research on how this works because now I'm even more confused. Do I need to jump wires inside the megasquirt at all to get this to work? Thank you so much for the help BTW.

[@OGPedXing]

Which megasquirt version do you have? This page has nice diagrams, the direct link is to the ebc notes but one level up and click on build the megasquirt, at the bottom it has the main ecu harness diagram. trubokitty.com/#/installation

[@TheOfficialWickedOne]

Can I wire my 1.6 Mac boost valve like this running a ms2pnp?

[@OGPedXing]

Yes, should be basically the same. Since it's a pnp, you may need to add a new wire to the options plug and configure that in tunerstudio to be "boost".

[@THEWRAITH1409]

I just purchased my valve and I noticed the connector is not attached to the wires. How do I know which cable goes in which hole in the connection?

[@OGPedXing]

If your valve is like mine it should have the two wires coming directly out of the valve, no connector. If that's not the case, it may have been damaged or defective. For the car side of the wiring, check out about the 11:45 mark in the video. The two wires will connect to the maf plug based on the year of the car. You just insert the stripped end of the wire into the connector. If this is too loose, you can get a small crimp on spade connector from an electronics or audio store...the spade needs to be very small. A simpler option may be to use some solder and a soldering iron to "tin" the end of the wire which will stiffen and thicken it enough to fit tightly. Let me know if this answers your question.

[@THEWRAITH1409]

@@OGPedXing I got a connector sent in the same package as the valve. The connector is made to match the connector on my car but it wasn’t connected. Does it matter which way I put the wires into the connector?

[@OGPedXing]

Oh ok, nice! Usually it comes bare wired. No the polarity of the wiring doesn't matter, one will be ground and one will be power but the valve operates the same either way.

[@THEWRAITH1409]

@@OGPedXing thank you so much for the fast answers!

[@nathanmacpherson2448]

Are you available and I can pay to help get my miata calibrated and tune installed I had to send ecm in for repair and I can't get idle to stay consistent

[@OGPedXing]

I don't really do remote tuning but I will sometimes look over viewers tunes and logs. You can send to my email that's listed on the channel About page (and click the contact button).

[@John-rw9bv]

@@OGPedXing wow you're a really nice guy!

[@justinmaynard8706]

Why does this differ from every diagram I've ever seen on how to plumb a three-port boost controller?

[@OGPedXing]

Always confirm with the diagram on your solenoid and also manually in the way I show in the video. Different models and makes are plumbed differently. The most important thing is if there's no power then you need to be on wastegate pressure, no boost. So the source line needs to feed to the wastegate via the normally open port.

[@norb231]

How did you know which base frequency to pick?

[@OGPedXing]

I'm familiar with this valve so I knew it actually likes about 32hz but the way to figure it out is to test how much air it lets through at various frequencies before closing. What you'll find is that as you go up in frequency, it will still work but the range from open to closed will shrink. So instead of a duty cycle range of 10 - 80% you'll only get 30-45%. What that does is give you much less control or resolution to dial in the boost really accurately. So in this case using either 26hz or 39hz will give good results.

[@norb231]

@@OGPedXing This solenoid has s rating of 30hz max

[@OGPedXing]

@@norb231 the tech data from Mac valves doesn't note the recommended range specifically but the total cycle time is 8 ms. Rounding up a bit to give some time in the open state, gives about a max of 100hz. You won't damage the device if the operating temp, voltage, and amps are not exceeded. However at higher than 30hz you just lose range so it's definitely not recommended to exceed that if you don't have to. Unfortunately some ECUs require you to pick a hz out of a small number of options so you have to pick the one closest to the best range.

[@norb231]

@@OGPedXing Thanks for the clarification I can leave it at 26hz then.

[@maxp8892]

I sent you an email about MAP on my 2002 NB, Under boost settings I don't have a Boost on the Boost pin selection. I'm running a MS3PNP. Can you help?

[@OGPedXing]

Hey, yeah, just saw the email. Basically the drop down will have only the options for pins available to your ms3 that can be set via software. Typically it will default to one of the pins on the options connector for this rather than a pin the goes to the stock harness and stock MAF wiring like I have on my home built ms3x. So I'd leave the default selection is tunerstudio and then add your own wire from that pin to the ebc. You'll have to confirm this but I think typically it's pin R is set up as the boost control on the ms3pnp.

[@maxp8892]

@@OGPedXing Is there a way to use the MAP from the stock harness & MS so I don't have to pull a new wire? Thanks in advance. You do such a great job of taking on projects and excellent explaination and details.

[@OGPedXing]

@@maxp8892 you may have to depin the maf wire from the main harness...checking the diagram from trubokitty, it seems to be 4X...and then connect that over to the options port pin. I'd probably just run the wire through maybe the bung for the cruise control which is above and behind the gas pedal and is to the left and below the brake booster on the engine bay side. But whichever seems easier.

[@maxp8892]

@@OGPedXing Thanks for the suggestions. Have a great day.

[@maxp8892]

Patrick, Do you know what / where I can get the crimp pins that go in the Mazda wiring harness that plugs into the MS? I need to add the wire but forgot about the pin in the connector. Thanks in advance.

[@ruffus4924]

I followed this and I cannot get my mac valve to work when I use test mode I don’t hear anything. It’s set under boost

[@OGPedXing]

You can try verifying the output wires your using with a voltmeter. With the boost valve disconnected, turn the test mode to on with a 100% duty cycle and you should see 12 volts on one lead and ground on the other. If you're not getting that, verify in tuner studio that the boost controller pin is defined correctly.

[@ruffus4924]

@@OGPedXing I have pin 7 on the options plug tapped into 2O in this harness, and whenever I go into programmable outputs and turn the boost output on tuner studio gives me an error. I

[@OGPedXing]

Usually the error will be something about the pin is already in use. You'll need to find what tuner studio is already using output pin 7 for and disable it or set a different output. Then it should work to enable the boost control settings.

[@mitsubishienthusiast3043]

This in a external wastegate sound is like to Subaru... "Flutter" wastegate no?

[@OGPedXing]

I don't get the classic "stuutututu" sound unfortunately. I have a blowoff valve so my car goes pssshht psshht. 🤣

[@chrisjewson2456]

I wired my ebc as Instructed, 12v wire came from the blue connector and other wire hooked up at the 4th wire from the left on the maf plug on my 89 na mx5, after doing so my megasquirt didn't want to connect to tuner studios and kept displaying error messages, if anyone has had this issue or can help resolve the problem that would be great. Cheers chris 👍