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5MGTE Guide with Microsquirt

34472 Views 57 Replies 23 Participants Last post by  Slidymk2
This is for the people who are looking to turbo their 5m-ge engine. This will sort of be a how to or at least how I did it. I had a turbo setup with a RRFPR and it never really ran well at all so I changed just about everything.
It is a pretty cheap setup in terms of cost but it is a full standalone setup. It was a pretty easy and straight forward install. Easier than even a PNP AEM on a 7mgte because of the multiplex crap that never seems to work right.

How it runs after 30 mins of basic tuning
Still needs a lot more tuning but it runs ok and boosts fine

Factory Service Repair Manual(TSRM) For the 85/86 supra

Main parts
Late year 5mge early years will work fine as well but you will need some of the later year parts
4 wire stock TPS Make sure the TPS works. Mine did not work so I pulled all apart and it seems like the ceramic solder points dont hold and it loses connection inside.
Stock coolant temp sensor
Stock ignition setup with stock VR pickups(2 of them)
$30~ GM 3 Bar map sensor
$20~ GM IAT(Any IAT should work I use a buick GNX)
$210+ 750cc high impedance injectors bosch style
$120~ Walbro 450 in tank pump
Stock fuel lines/rail/FPR
$360~ ECU is a Microsquirt V3 with the 8 foot harness yes Microsquirt
CT26 with 7mgte exhaust manifold
$50-$150~ Oil feed and return lines soft line kit works the best(rabidchimp, arizona performance, drift motion, ebay ect)
Return bung welded oil pan
$50-$350~ 2.5 inch IC pipes with matching IC diameter(can be same side exit or normal or even stock 7mgte stuff)
IAC removed and blocked on intake
EGR blocked on intake manifold and head/exhaust side
$125~ Wideband O2 sensor I use the LC-1 but a cheaper one is the Spartan V2 from 14point7 which should be fine
Downpipe with O2 bung
Turbo to airfilter pipe(accordion pipe)
Colder spark plugs I used NGK BRP8ES

This runs $1100~ plus whatever it costs you for the parts that dont have prices next to them.

Recommend/optional parts
Oil filter relocation kit(cant replace filter without pulling turbo without this)
Stronger clutch if running more than 5psi or sticky tires mine was new and slips
Bigger radiator with electric fans( I use a MKIII aluminium one off ebay)

Microsquirt ECU is basically Megasquirt V2 with some unique features and some missing features
The V3 version is important here because it has dual spark. Update to firmware version to MS2/Extra 3.3.3
It does not have stepper motor controll so it cant run the stock IAC but if you want an IAC you can get a PWM valve.

Fuel setup
Drop the tank and install the walbro fuel pump in the stock pickup
Install the injectors into the stock fuel rail.
Replace the fuel filter

You can run any size injector you want I just chose the 750cc because I plan to run e85 at 15psi of boost
Just make sure whatever injector you run is high impedance OR you have resistors installed inline as the ECU cant run more than 2 if low impedance.
Also check your injectors before you install them one of mine was stuck wide open and flowed full flow of gas directly into the intake manifold filling nearly
the entire engine with fuel
Fuel injector wiring makes this batch injection the microsquirt does not have enough outputs to run sequential injection
The injectors and ECU need to run off the same 12v relay
You should solder and heatwrap all connection you make if possible
The stock fuel pump relay is triggered off a wire that normally runs off the stock AFM
You can wire this as shown in the images to have it run off key on

Begin by removing the entire stock engine harness and ECU. The harness will pull through the firewall without needing to cut anything off.
Cut the TPS and coolant sensor connectors off you will be reusing them.
Wire using the diagram below and the microsquirt website here
All of the wires on the harness that comes with the ECU is labeled
You need a switched 12v power supply from a relay for the ECU and injectors

Turbo/charge piping
Trim the exhaust manifold to clear the power steering bracket a grinder worked for me.
Pull the oil pan and get a bung welded to it. I suggest a -10 AN bung for the drain.
The block has a oil port on it which is BSP thread use that for the feed. You can buy BSP to -4 AN if you are using AN
Double check the wastegate is working and install the turbo make sure you have gaskets where needed.
Routing the intercooler pipes can be a pain and is up to you how you want them routed.
I suggest using T-bolt clamps for everything if you can
The charge piping needs to flex a bit as the engine moves side to side under loads.
Install the downpipe I would not recomend a stock MKIII one
You can get a nice elbow and get a downpipe/exhaust made at a shop for pretty cheap as well.

Also if looking for parts on Rockauto
Look under celica then select 2.8l engine
Way more selection compared to selecting supra on the list
This is the best way to buy OEM type chassis parts like bushing that I have found.

Wiring diagrams

Tune setup
Calibrate your TPS
Setup for your wideband and map you are using in the settings
Input the general settings and the basic tune settings.
ECU needs power when you burn the settings to it.
Also needs a reset(power off and back on) for some settings after you burn them.

Most important part to get your timing correct
On the ignition options menu the tooth angle will need to be adjusted
For example on my setup I had to set the dizzy a tooth retarded to get it to zero out base timing
It might need to be 0 degrees or 30 degrees on your setup for the tooth angle number 1 setting
To set this correctly you need to set the fixed advance option to Fixed Timing
Using a timing light on the crank while the car is running, adjust the tooth #1 angle to get the timing to match exactly timing for fixed advance setting
I used 0 for the fixed advance setting and had to set the tooth #1 angle to 9 degrees
If it does not match going down to 0 on the setting you might need to retard or advance the distributor or even jump a tooth on it.

My car would start on rising edge setting but it would lose sync all the time at higher RPM
Falling edge cured that but it changes the timing by around 22 degrees
It is very important to make sure the ECU sees exactly the same timing as the engine is running at

This is a rough tune I made using some of the other tunes posted on here for the 7mgte like williamb82's tune in the megasquirt thread
I have driven this tune approximately 50 miles. Its a pretty safe tune I feel, AFRs run low 11s to low 10s at high rpm on boost
Max boost I have seen is about 145KPA on this setup which is around 6.5 psi I will be adjusting the tune and boosting a lot later on.
You can tune and adjust settings while driving you dont need to reset the ECU for every adjustment
ECU will show 1 sync loss every time you burn the ECU if engine is running.

Direct Link to the MSQ tune
right click save as
Make sure the file ends in .msq
not .txt

Main forum for the MSEXTRA if you have issues with the software or anything else with the microsquirt

Anyone else who has a turbo 5 or 6m or 7m feel free to add some advise on the tune

1/4 times on this setup here
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Bravo sir. You had the patience to do what I did not, make a guide for 70% of the population to ignore and still ask the same questions over and over (which is why I chose not to do it) After having gone through everything you have, I know every minuet of whats involved.

Your effort put into this for the forum and to spread knowledge is very commendable!
Hopefully this will help the people who deserve it and truly want it.

This most definitely should be a sticky!!!
Thanks it is pretty hard to find some of the info to get everything to work right. I am thinking of buying the full version of tuner studio to have it auto tune the car to clean the tune up.
Just not sure how well it works compared to just adjusting it while driving around.

These same settings or similar should work on a 2jz with a stock distributor and a 7mge
I think most of the toyota stock VR pickups are 24 tooth main wheels with either 1 or 2 tooth secondary wheels
The setting to adjust this would be 2nd trigger active on and every rotation of crank/cam depending on number of teeth on the 2nd wheel

Here is the car on 9 psi
well looks like im gonna have to swap from the diypnp to this setup and maybe ill finally get my car running again. thanks for this awesome write up. Now i have a big question, with the pnp i have i can setup a 2step box, now will i have the capabilitie of doing the same with the micro
Yupe it has launch control options,flex fuel and the same boost control settings
Its really the same thing as the MS2 but some of the features are either limited a bit or different in how they work.
For example I think you can only run 2 coils on the microsquirt vs 6 on the MS2 and no IAC control for stepper motor idle valves but PWN valves still work
Also no on board map sensor. One of the main benefits is the way the microsquirt reads the VR sensors which is hardware based filter on the V3 version vs software based on most of the others.

More info on the ECU itself here
and older info here stating its basically a MS2 unit

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Thank you for this post. Very informative and learned more about the 5MGE wiring. Much appreciated.
Very nice work, i will for sure use the sensor info that you have so kindly spelled out for us.
I switch the car to E85
It was very simple I pulled up to the gas station on an empty tank of 110 and drove away on E85.
Set the required fuel target afr to 9.8 which will increase the injector pulse width
Basically richen up the fuel table by 30% and start the car have some tune to get the AFRs in range from there
It will be really rich on start up. Tune off of gas AFRs as most wideband run on lambda.
Max power feels like 11:1~ afr on E85 vs the normal 11.8:1 on gas.

Car cruises at 14-15:1 and idles at 12ish on this tune
Timing could be advanced quite a bit but I am still tuning it
Boost control is setup with a MAC valve on a stock WG
Seems to work pretty well and will stay steady.
Depending on wiring higher numbers could be more boost or less boost
I have a flex fuel sensor just need to install it to see what percent ethanol it is right now.
If I had to guess its 78-80% for this tune

Some videos

14psi bad traction
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Nice work as always. Will microsquirt do map blending?
Hell yeah, awesome job!
Nice work as always. Will microsquirt do map blending?
Not sure if it will do map blending I do see the options on the tunerstudio but not sure if the ECU has the hardware for it.
MS3pro has blended maps I think normal MS3 might as well.

I think how it is done on most megasquirt v2 or microsquirt setups is via percent fuel and spark in degrees
Flex fuel sensor works in a range of 50hz to 150hz and the ECU will know what percent ethanol the fuel is based on that frequency
So say if you wanted to run pump gas on the E85 tune you can tell it to multiply the fuel by say .70 and pull 5 degrees of timing depending on the hz reading.
If you had a pump gas tune and wanted to run e85 you can have it multiple the fuel table by 1.30 and add 5 degrees

It normally would work off a curve not simple one of the other like above. Most E85 is not actually 85% ethanol it normally between 70 and 85%
Normal gas now is 10% ethanol which it needs to know that as well as the hz wont be 50 it might be more like 59 or 65 for pump gas
These numbers are guesses for now because I have not installed the sensor. Once I get it working right Ill post up the settings I used
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I'm not familiar with turbo's, but appreciate all the work and documentation you did. Great job!
Flex fuel setup
So this is how it works with a GM(Continental) sensor.

Stock GM sensor runs 50hz for pure gasoline(0%) and 150hz for pure ethanol(100%).
Fuel multiplier% multiplies the injector pulse width. This will increase the amount of fuel or decrease it based on ethanol percent.
Timing addition is how much timing is added or subtracted in degrees not percent. This is on a curve like the fuel Do not set both to negative my car started showing 80 degrees advanced
Baseline percent ethanol is whatever ethanol percent your fuel is on the tune. So for people running pump gas(e10) it will be around 10%. If the gas is pure set it to 0%
Mine was a reading 70% on the sensor so I set it at that. Most e85 is between 70% and 85% depending on season
It will say what your percent is when you set it up. You need to add the ethanol percent gauge to the dashboard in tunerstudio to see it.
Fallback settings are if the sensor fails it should be really rich with no timing addition to be safe.

As far as reducing boost based on flex fuel input you can do that but I think it is a paid only with tunerstudio.
Or it might be a MS3Pro only feature as it is greyed out on my version. It could also be I need to set my boost control to advanced setup with PID settings.
Ill look more into that later. I plan on running e85 almost always. The flex fuel will just be so I can get home if I happen to run out of fuel somewhere.
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Love this build I'm in the process of getting my microsquirt ordered

Sent from my SM-N910T3 using Tapatalk
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Dude this is fuckin awesome, bookmarked and will reference again in may-ish once I'm out of school for the year and have a job so I can finally slap my turbo on the 6M! The computer stuff was the main reason it's not already turboed but this will make that lot easier, thank you!
Whoa, didn't realize OP was local... hello there, so when can I come check this bad boy out? :D
great write up. i may have missed it, but what did you do or calculations did you run to figure out the base ignition table? Also, why microsquirt instead of the full ms2/ms3? I look forward to your response
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