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Any questions you have before you begin buying, building and installing.
I have an EP91 Starlet which i'd like to get a Speeduino going on, i have had a look at the wiki but that left me with a few more questions than answers.

I'm not asking for someone to give me wiring instructions or anything like that. But i have some more general questions, specific info for a 4E would be great though.

My first question is am i likely to have issues just wiring the Speeduino in to existing wiring (just replacing the stock ECU). Are there any sensors i may need to add or check on my current engine if they will work before i wire it up?

I assume a 0.4 board would be suitable for this engine in N/A or Turbo form?

I'm a bit confused about the crank angle / camshaft sensor, this i suppose is more a mechanical question but i will need to know what my engine has (not 100% sure where to look) and use that. Since this is specific to the engine any advice that would help me get started figuring this one out would be great.

Can a base map be setup with the car still using a narrow band O2 sensor?

I'm sure i will have many more questions but i don't want to go overboard just yet. Essentially just need a leg up to get started, thanks in advance.
I've done some digging and got a very very very rough and probably wrong idea of what Speeduino wires go where on the factory wiring for the car.

I've noticed a few topics where people have done this before but there's not many fine details in the posts.



So far my assumption on wiring is in the attached spreadsheet. Feedback on what i've got so far would be appreciated.
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The info you need is found in the workshop manual and under the hood of YOUR car. Read and compare it carefully with your actual engine. In the manual you should find specs of all parts.
Wires and engine parts may have changed over years or in local versions. Chances someone fitted exactly your version with a Speeduino are very low. Do not start until you understand all the stuff in the engine bay.

(Please do not take this persona, but I´m sometimes worried how people, that are not even aware what is under the hood of the own car, can hope to DIYS it with a new ECU or even fit a turbo.
There are people who can do it and some that are better off by having it done by a pro. The second option is the usual way, only a fraction of people DIYS. These are usually qualified in computer stuff, electronics or mechanics, most in all 3 plus "usual" crafts, such as welding and machining stuff and have a load of tools.)

Sure you can do some kind of P&P ECU installation with the stock loom. If you connect all compatible sensors, injectors and coils and retrofit what is not compatible. In most cases will that be ignition coils and cam/ crank sensors.

There are break out PCB available, where you can solder Spseduino wires to a stock connector and insert necessary extra parts.

Without a wide band lambda controller and sensor it is impossible to start a conversion. Fit it and make it work BEFORE you start to install anything new to the engine. If it works on the stock engine/ECU, you are fine. If you are able to get a WB lambda installed and working, maybe think about another ECU. If not, it does not gest simpler on the way to a custom ECU...

Make sure your engine is in top condition. A programmable ECU does not fix a worn out engine burning oil and can not be tuned well.
Completely understand where you're coming from. Unfortunately this particular engine the workshop manual is notoriously difficult to track down as Toyota are the only ones with rights to publish it. I'm keeping my eye peeled for when one comes up for sale.

This car is a project / event car for myself and therefore i have the luxury of time to check wiring, sensors, etc so i know how it works and how to interface the Speeduino with the engine. My strengths are in the computer and electrical side of this i have a more basic understanding of the mechanical aspects but are more than capable of repairs etc. Usually people like myself do not have access to / the need to get into the nitty gritty of the output of sensors and the lower level functions these play in the running of the car by the ECU.

Was fairly certain i'd need a wideband for this so before i go out and start throwing money at that. The best starting point will be to check the existing sensors, injectors, etc on the engine and ensure these are compatible with the Speeduino or what additional circuitry is required to make them compatible.
A few things but they at this point are more specific to my engine i.e is X Y Z compatible with Speeduino currently and/or would sensor changes be needed to make the Speeduino compatible.

I will do some reading and start checking what the cars has currently in terms of injectors, sensors, etc. Just start knocking things off one by one.

Will post again as you said with specific questions about say TPS. Its all a bit daunting at first but breaking it down should be fairly straight forward.

The plan being is checking existing wiring and sensors on the engine to determine what if any changes may be required for Speeduino to control it. Then addition of a wideband and some data readings to get an idea of how the engine is currently running (which i assume will be useful for creating a base tune). Then wiring up a Speeduino and going from there.
Don't bother data logging current engine and ECU.

It's not actually useful at all.

The firmware comes with a base tune which is generally close enough to get most engines started once you have changed the options to match your engine.

Once running you then start tuning.
When i did a corolla and starlet both with 4efe i googled. Everything is readily available, including wiring harness. I even found trigger setup and trigger angle on a megasquirt setup, so i was able to recalculate to speeduino trigger angle.

I was able to gather enough information in one night of googling, that made the car start first try.

I ran a Toyota V6 on standard loom and an adapter that is readily available from one of the Speedie stores. add a few jumpers and its good to go. well mostly.

I'm not familiar with the 4E-FE. But my 3VZ-FE runs a dizzy and has a fancy VR pickup's, which I could never get to run right, I have not heard of may success story's on here about getting a stock Toyota Dizzy VR's to function 100%.

All the toyota sensors are fine. My VZ injectors where high impedance so fine, and the stock ignitor worked find.

So good luck and enjoy.

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