For any discussion not specifically related to your project

Update v3 - 10 Jan 2019 - this was so old it was rubbish, so I totally rewrote it with what I've learnt - new in blue -.

People will try to help if you have a problem, but ultimately you will have to do the reaserch and work everything out.
The people making this happen make nothing doing so, and the help is just volunteers giving their free time.
******************************IT'S UP TO YOU TO GET IT TO WORK******************************

I'm a beginner, and when I started you couldn't understand much here without an electronics background. There was no central comprehensive instructions and bits of information were all over the place, so I read the whole forum and summarised it in this guide so everything relevant was quick to find. Prices are in $AUD unless stated.

A lot of problems have been fixed, instructions, supply, and more people involved and helping.
The Wiki still isn't fully detailed, but now there is enough to get you running. Hookup and actual tuning still needs work.
There are also multiple platforms to ask questions, i.e. Forum, Facebook, Slack, with the forum still being the best.
Supply is better these days with people selling kits around the world on easily accessible selling sites.

COMPULSORY before you do or buy anything - 1 hour here will save you 100's latter-.

Read every word in the Wiki before you begin - questions are still asked that are answered in the Wiki, and that wastes everyone's time -.
Read every word in this first post before you begin.
It took me a week reading the forum front to back to know all this, so trust me this is the quickest way.
You can even buy a MEGA2560 and load the Firmware and play with TunerStudio before you make a decision to buy.


PROCESSOR - $12 - $22
Arduino Mega 2560 R3 16AU - ATmega2560-16AU Board ( Arduino and compatibles )
The Arduino Mega 2560 was chosen because it has 4 hardware timers, uses simple well known Arduino IDE code for common Atmel chips, and is the cheapest - this project is all about cost -. Other Arduino's don't have enough timers or use different chips that have different instructions, so will not work.

There are 2 options for the serial chip on the Mega 2560, the ATmega16U2(small square chip near USB) version that connects to the PC the best, and the CH340(larger rectangular chip near USB) version having communication problems.
Use Bluetooth if you have a CH340, or read here if you want to work around the problem with the chip. ... emite.html
The problem with the CH340 is that the Win drivers are flaky, so use the CH340 manufactures driver.

MAINBOARD - $138 - $160, DIY $?

Buying from the official store probably helps the project, but if you are in a country with high postage from Australia there are sellers around the world. Search Ebay, Speeduino Forum, and Facebook.
Speeduino is as hard as you want to make it, i.e. buy it assembled is easy, redesign it, source parts, and build it is hard.

Speeduino Assembled : Official(quality parts) - $160
A bit more expensive, but you will get that back ten-fold in less problems and time being wasted.
Speeduino Kit : Official(quality parts) - $138
Is just as good if you have electronics experience, but mistakes can happen with inexperience. Anytime I see problems with the official kit it's nearly always a mistake by the assembler, i.e. parts in backwards, solder shorts, dry joints, etc.
Speeduino Assembled/Kit : Unofficial sellers
Because Speeduino is open source there are many suppliers all over the world - probably near you -, so you will have to research what you are actually getting, i.e. some use official PCBs and source parts(branded/unbranded), some get PCBs made from the original plans, some totally redesign the unit, etc.
Speeduino Kit : Self Sourced(unknown cheap parts)
There is no reason it shouldn't work, and it's fine if you don't have problems. But if you do have problems, you are never sure if it's the software or hardware. Basically it's quicker to solve problems if the MB's quality is taken out of the equation. There are also other problems, like are cheap parts going to fail long term, do they perform the same, i.e. fake copies, is a homemade PCB going to fail with time. etc. Even the initial price isn't much cheaper, but like all things Ebay you get so many spares that all subsequent units end up being very cheap. My 2 Speeduino's are all Ebay/AliExpress parts, including fake copies, and they do work, but you have been warned.
Speeduino DIY
Because Speeduino is open source you can make the thing just from the plans. You can redesign the PCB, DIY home PCB etch or cheap professional PCB made from the gerbers, source parts, and assemble it, just remember this one is the same as above but with added potential problems. I did mine the DIY home etch/Ebay AliExpress way, and it was hard for someone with no experience.

Mainboard - assembly and config
To assemble the board you need the Wiki picture and the BOM(Bill of Materials) - link at bottom of respective Wiki page -.
Video Guide - Assembly -
Mainboard - hookup and wiring
The output pins haven't been fully defined and there are no actual hook-up instructions or diagrams, so you have to sort that out yourself or ask - pic at bottom of this post is the best so far -.
Mainboard - circuit designs and BOM files
***** ... e/hardware


Conditions high voltage analogue sine wave to digital 5V square wave.

MAX9926 - dual VR
Official design - tested working fine. $28
DIY Github files - small SMD chip is hard to work with if you DIY.
***** ... onditioner
JBperf - too expensive so not used.

LM1815 - single VR
DIY design - I merged the 3 designs and have it working.
If you permanently add this to your MB design you have to isolate the chip, i.e. jumpers or remove chip, if you want to switch back to Hall/Opto or it will ground the signal.
Reference design links. ... 5&start=60 ... 6&start=10

Optically isolates the high voltage coil signal from the Speeduino if you want to run fuel only off the original ignition.

Official design - uses the other side of the VR board.
DIY design - I accumulated all the other designs and added it to my Speeduino but I haven't tested it yet. Others have their versions working.
***** ... 6&start=20
Reference design links. ... 5&start=60 ... 5&start=80

It's not likely you will ever be able to tune your engine without a oxygen sensor, and as a bonus TunerStudio paid version can auto tune the VE fuel table with it to save time. I recommend WB(Wide Band) because using a NB(Narrow Band) is slow and inconclusive. It is possible with a NB, but it won't be super accurate and will take ten times longer.
There are many WB that will connect with Speeduino, but I will only mention the cheapest.

SLC Free (Sigma Lambda Controller Free) $35USD - only uses the newer Bosch LSU4.9 WB sensor. I recommend SLC Free B $45USD with text display.
Instructions -

APSX D1 Digital Wideband WBO Controller Module (Board) $25USD - only uses the Bosch LSU4.2 WB sensor. The LSU 4.2 is slightly less accurate, but overall it's still more than capable if you want to save money.

Bosch WB sensors - LSU 4.9 is always designated 0 258 017 XXX. LSU 4.2 is always designated 0 258 007 XXX. They are not interchangeable.
Bosch WB sensors are known to fail if their heater element it turned on when they have moisture on them, so it's best to run a delay start until the started engine can dry them out. You can use a spare Speeduino control pin or run a delay board. ***** ... er&_sop=12
Never buy cheap unknown sensors because they are all fake copies - I will be testing a fake copy latter to see if it's good enough -.

Arduino DRV8825 Stepper Driver - $2
***** ... pell_check
Plugs directly into V0.4 boards, but others have no provisions so have to be manually hard wired if they are needed.

Smart coils have them built in, but it looks like you can use any N-channel IGBT - P-channel is not common -.
The pull-up to reset the IGBT is already on the mainboard, so you only have to connect the trigger signal to the GATE, the coil negative to the COLLECTOR, and the ground to the EMITTER. Heat sink is preferable, but make sure you set TunerStudio Spark Settings to Going Low or it could burn out.

I don't know much about this other than it supplies tach output and control for extra things, so you will have to research it.
***** ... 6&start=10

Some old tachs need a big flyback to run, so this is how.

I think it can do WiFi, but everyone goes for the Bluetooth. You only need the slave HC-06.
Bluetooth HC-06 - $3
***** ... 6&_sacat=0


Monthly Release
***** ... g_Firmware
Intermediate Releases - bug patches
As far as I can figure out you download the whole thing with the green button, and pick through it for the updated firmware.
Note : If you are updating the firmware you don't lose your tune, just upload the new speeduino/speeduino.ino to the MEGA2560 and start TunerStudio and point it to the new reference/speeduino.ini.
Video Guide - Pt1 : Getting Started - Firmware -
Video Guide - Pt2 : Setting up for TunerStudio -

TunerStudio MS - $0 free ver - paid ver $70USD(on special $60USD)
Paid version has autotune.

MegaLogViewer MS - $0 free ver - $40USD(special $30USD)+
Free version isn't very useful because it only does 400 records. Not essential, but quite useful.
EmproDatalogViewer - $0
Simple but free and unlimited.

Not essential unless you want to bench test it.

Ardu-Stim - $0(requires an Arduino)
Video Guide - Pt3 : Trigger Simulation -

Simple Oscillator
You can rpm trigger a Speeduino with a simple oscillator. Maybe one of these - I can't remember if I tested it -.
***** ... r&_sacat=0

There are so many designs on the forum I'm only going to link mine because I have it running. I find a built-in oscillator much more convenient so mine has one, along with provision for an Arduino to run Ardu-Stim.
Video Guide - Pt4 : Sensor Simulation -
Video Guide - Pt5 : Output Testing -

JimStim - $28USD
I don't know much about it, but it looks like you can DIY it - not tested

I don't know how anyone can be doing tuning without a timing light, so get one or build this cheap DIY LED one.

Not essential, but quite handy.

It's small, portable, and has become essential for me. Buy the original JYE and not a copy, because it helps the designer.
Original JYE Tech DSO138 DIY Digital Oscilloscope Kit SMD Soldered 13803K Version - $21
New version
Original JYE Tech DSO-SHELL DSO150 15001K DIY Digital Oscilloscope Kit - $29

Xprotolab Plain - $20USD
The $20 version uses a PC to display traces, but I don't know much about it. Could be good. ... -plain.htm

There are plenty oscilloscopes so look around, but this is a cheap one the forum found.
Hantek 6022BE PC-Based USB Digital Storage Oscilloscope 2 Channels 20MHz 48MSa/s - $75
***** ... BE&_sop=15

Video Guide - Pt6 : Triggers Explained #1 -
Video Guide - Pt7 : Triggers(crank) w/ IGN Demonstration #2 -
Video Guide - Pt8 : Triggers(cam) w/IGN Demonstration #3 -

No experts have corrected errors or filled in missing sections, so this is my beginner interpretation of the layout.
This uses the V0.4 as an example and doesn't have the individual wires shown, but at least you can work out what you need and what to research.
right-click save drawing and zoom in with picture viewer -.

Trigger Sensors
VR(Variable reluctance) - Mainly 2 wire.
VR makes it's own voltage so only needs 2 wires.
VR makes voltage in an AC way so the output is a sine wave alternating from positive and negitive
VR makes voltage when a ferrous metal passes it, and can reach 130V.
VR needs a conditioner to change the high voltage sine wave to a 5V square wave.
Hall - Mainly 3 wire.
Hall is usually powered so needs + and - and has an output wire back to the Speeduino.
Hall senses magnetic flux to produce a signal
Hall usually has conditioner built in so it outputs a 5V square wave. 12V square wave ones have to be reduced to 5V.
Optical - Mainly 3 wire.
Optical is usually powered so needs + and - and has an output back wire to the Speeduino.
Optical Mitsubishi units(4G63) have conditioners built in and are usually(?) powered by 12V and output a 5V square wave.

Dumb coils - Mainly 2 wire for singles, but more for packs.
If you see a coil-on-plug(COP) with 2 terminals it's probably dumb and needs an ignitor unit.
Smart coils - Mainly 3 wire for singles, but more for packs.
They are powered so needs + and -, plus have a trigger wire from the Speeduino to tell it when to fire.
I'm not sure every 3 wire COP is smart, so check it before buying.

inj1 - Injector channel #1 - Speeduino GNDs injector channel #1 to control it - To negative of injector
inj2 - Injector channel #2 - Speeduino GNDs injector channel #2 to control it - To negative of injector
inj3 - Injector channel #3 - Speeduino GNDs injector channel #3 to control it - To negative of injector
inj4 - Injector channel #4 - Speeduino GNDs injector channel #4 to control it - To negative of injector
12V - 12V power in - Connect to power source that supplies 12V when key is turned to ON or RUN
GND - Ground or negative - Connect to any ground point
Idle - Idle Air Control valve(IAC) - Control of ON/OFF or PWM IAC valves by GND - Connect to negative of IAC
FP - Fuel Pump - Control of fuel pump relay by ground - Connect to negative of fuel pump relay
S2 - Optional control - Control Thermo fan, VVT, Boost, etc - To GND of control relay or directly if under 1 amp
S1 - Optional control - Control Thermo fan, VVT, Boost, etc - To GND of control relay or directly if under 3 amp
ign1 - Ignition channel #1 - Triggers ignitor channel #1 - To signal IN of ignitor or smart coil
ign2 - Ignition channel #2 - Triggers ignitor channel #2 - To signal IN of ignitor or smart coil
ign3 - Ignition channel #3 - Triggers ignitor channel #3 - To signal IN of ignitor or smart coil
ign4 - Ignition channel #4 - Triggers ignitor channel #4 - To signal IN of ignitor or smart coil
IAT - Inlet Air Temp sensor - To IAT sensor
IAT Ret - GND for 2 wire IAT - Not needed if IAT GNDs to car body
CLT - Coolant Temp Sensor - To CLT sensor
CLT Ret - GND for 2 wire CLT - Not needed if CLT GNDs to car body
TPS - Throttle Position Sensor - To signal OUT of TPS
TPS Ret - GND for TPS - Not needed if TPS GNDs to car body
vref - voltage reference - supply power to 5V sensors - To + of TPS, external MAP, etc
O2 - Oxygen sensor - To signal from NB or WB controller
GND - Ground - Ground connection
vref - voltage reference - supply power to 5V sensors - To + of TPS, external MAP, etc
VR1- - To negative side of main VR sensor
RPM1 - To signal of main trigger, ie Opto, Hall, or + side of VR sensor
VR2- - To negative side of secondary VR sensor
RPM2 - To signal of secondary trigger, ie Opto, Hall, or + side of VR sensor
Last edited by Old Grey on Sat Feb 02, 2019 3:28 am, edited 137 times in total.
Old grey , I understand you feel frustrated but some of your comments are a little unfounded!
We are not all from the industry, many of us are from other lines of work or even retired!!
This project is DIY and makes no promise to be anything else. It does require some patience and a little skill/work
If you don't want to make your own main board which really is the open source way there are two main sources for the main boards, the shop which Josh aka noisymeme operates, or from edc_atl who usually has some in or on short supply notice.

Layouts are on the git and component lists. If you cannot assemble or SOLDER then get a simple kit from maplin or another supplier and practice first do not attempt to build this if you cannot do either of the former mentioned skills and then moan it went wrong!!
Fully made units are still under discussion but will come from 3rd party as Josh really doesn't have the time for that.
You can purchase all the components from one supplier, I used mouser for mine.

Richcreation's boards were designed as a favour to help out, but cost very little from osh park to have made even if you only need one.again edc_atl has an alternative board for the vr available if you want.

To describe the firmware is flakey is very unfair and hurtful on all those involved especially josh.the code is under development and is not an actual release version as such!!!

The wiki is under work ,but like all things take time

For testing ardustim is cheap and simple and for other inputs a simple variable resistor is fine,that's how I test mine!
You don't need a scope, I have two boards up and running made and tested without one!

Finally , remember this is a hobby project, worked on by busy people most of whom work in or run busy jobs in there spare time for no pay!!!!! If you need help we are all here to do so on the forum .
Thank you for the guide. I came to similar conclusions. But it's still very early days for this project, so some bumps are expected.
If you are interested in a single PCB, you can just ask around if someone in your continent can sell you one. I asked on the forum and immediately received an offer to send one for free. So you don't necessarily need to manufacture one by yourself.
As for instructions, I think you need to look in (or whichever version you work on) and then use bill of materials (BOM) and functional diagrams from github to assemble the board: ... dware/v0.4

All that said, I haven't assembled any speeduino's so I might be wrong :)
I agree that some of that is a little harsh. But i can understand the frustration.

I am running my daily car on one for the last 2 months, and the firmware would easy be that old too, yes there are updates but thats mostly to add more features.
NickZ wrote:I agree that some of that is a little harsh. But i can understand the frustration.

I am running my daily car on one for the last 2 months, and the firmware would easy be that old too, yes there are updates but thats mostly to add more features.
Cool to know that someone is dailying a speeduino :) By looking at the projects thread I didn't have an impression that someone is already using it for more than just experimentation at this point.
I don't think people are reading the guide correctly.

I get accused of this
dazq wrote:To describe the firmware is flakey is very unfair and hurtful on all those involved especially josh.the code is under development and is not an actual release version as such!!!
Because I said this
Old Grey wrote:If you want to risk possible flaky FW, more often updates are here.
When I plagiarised it right off the Wiki page
Wiki wrote:If you want the latest and greatest (And occasionally flakiest) code, the git repository can be cloned and updated.
You have to blame Josh for insulting Josh, not me.

You currently have to have electronics knowledge to do the Speedinuo simply because there are no full instructions yet - I can build any kit so long as there are instructions -, but imagine a plumber or carpenter or even a mechanic, how are they going to do it.

Lets look just on this page for words I didn't know 4 days ago :-
Mega 2560 R3 16AU
Dual VR Conditioners
osh park
Now imagine all the new words I had to look up after reading the 3000 posts.

I'm trying to help you by not frustrating beginners and summering the 3000 posts in one location, because no beginner is going to read the 3000 posts.

Last week a guy installed components backward, and two days ago a guy nearly bought the wrong Mega 2560, simply because the information isn't in one location or just not available. I just wanted to avoid that because it's a simple fix.

Tell me what you don't like and I will explain it to you from an outsiders perspective. Or better yet help me make this guide better.
Well done. Image I did not take any of it as harsh or misleading at all. For example, the listing of the "stable" code, but also the potentially flaky GitHub code - which we are all aware really is flaky sometimes, as it is un-tested code.

For parts listings, there are a few posted BOMs (Bill Of Materials) that can be useful, but suppliers have changing stock daily, and it's up to the user to determine both the parts necessary for the project, and alternate parts if listed ones are not available. It's just part of the situation that we have no control over, and must each deal with, until someone steps-up to invest in complete kit pre-orders. To be fair, that is unlikely for a while, as this experiment is evolving with newer and better stuff regularly. That means it's a risk to invest in kits for re-sale that may be obsolete tomorrow.

As already stated, there is no room to make any money in this area at this time. Perhaps one day soon. In the meantime, it is an all-volunteer effort by a bunch of folks that want to see the concept succeed. I think this diagram and point-of-view info is a good example of that.

PS: I'd suggest a slight change to the ignition section, as simply up to 4 outputs to dumb coils with ignitors or smart coils, of any variety (COP, CNP, packs, dist, etc) to indicate the system's flexibility — without having to draw all the types as done with triggers. You have a unique grasp on the diagrammatic method, so I'll leave it at that for you. ;) I look forward to the sexy final version to post in the Wiki. Almost there. Rock on, dude.
I did the attached Bill Of Materials for the full 4-channel setup, on the v0.4 board, including all spare outputs and MAP sensor. I updated the BOM Noisymime includes in the code. Note a few things that I changed or still need to be chosen:
  • If ordering for only 2 channels, or fewer functions, the extra related parts can be removed per the schematic.
  • I changed 8 red LEDs to 4 red, 4 yellow, and added 3 green for diagnostic indicators.
  • The case is the suggested Hammond with plastic ends. Others with AL ends also at higher cost.
  • > > > No pins or parts for trigger input requirements. Determine the input you need, add those parts, and order the necessary input board separately.
  • No connectors for wiring or wire looms.
  • Their stock changes daily, so be ready to find alternate parts from them, but this BOM is fillable as of the date listed.
  • Does not include the Mega. Does not include the PCB (order boards from the Store or edc_atl)
  • Total is about $88US with case, or about $72US without, plus shipping. Mouser has very similar final pricing.
I did this for me to update the one on GitHub, and you can borrow from it or Noisymime's version to get started if you like, at your own risk. If you aren't sure what you're doing, then please order from The Speeduino Store, or another volunteer vendor. I do hope that the designers or other sellers (edc_atl?) might get kits or assembled boards together, as digging for parts online is a big pain for most people, and I would think kits would be popular compared to dealing with BOMs. Not my decision though. Hope that helps!


BOM for v0.4 downloaded from DigiKey, in-stock as-of 29OCT15:
BOM for v0.4 from DigiKey, in-stock as-of 29OCT15
(16 KiB) Downloaded 725 times
A UK company called maplin electronics used to sell(they may still sell) electronic kit that required you to solder them together. These kits had a difficulty rating based on the complexity of the assembly , the testing and general skill of the kit assembler they ranged from 1-10 at that time. I personally feel that if we are all truthful the speeduino IS a complex project that requires some skill especially with testing and implementation , going by what those maplin kits were like the speeduino would be a 20!!ie not for the proper beginner!!

I feel that to use the term flakey is bad enough once in the wiki as I personally would read that as a bit dodgy which as stated the firmware is not and running many car Inc daily drivers, but I still feel that it is wholly unnecessary to repeat that poor choice of words in a beginners guide or anything other guide for that matter.

I am simply relaying some of the poor experiences I had when first starting out in electronics itself and the frustration and sadness when the chosen project proved to be too far beyond my skill set and don't want others to have those same setbacks.
Don't mean this to sound crass or disrespectful, but is this going to be something like a "Speeduino for Dummies"?

I'm all up for it, but think it should be at least "private", as in something non-registered users aren't able to read. As it evolves, "public" versions could be released... but I think this also should mirror the Wiki...?

I'm happy to write up verbose meanings for various things ancillary to Speeduino, such as sensors and stuff that I can glean from the interface boards.
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