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-   -   break down standalones for me (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/break-down-standalones-me-885285/)

ineedfc 01-31-10 09:27 PM

break down standalones for me
 
im a pretty proficient mechanic but i have not had the chance to ever see how standalone engine management works. is there a guide on how to use one or useful info anywhere?

Rob XX 7 01-31-10 09:41 PM

you can download some software and look around, you can DL wolf's right from their site

ineedfc 01-31-10 10:15 PM

fuck it i dont think this is something thats going to be easy to learn on the internet or by reading im probably just gonna have to get someone to show me.

misterstyx69 01-31-10 11:29 PM

look at the RTEK..
www.pocketlogger.com There is nothing to adjust on some of the 'chipped Ecu's'..like the 1.5,1.7,and 1.8 versions.
the 2.1 is programmable..Plus there is a a RTEK Section right here on the RX7 Club.
here ya go : https://www.rx7club.com/rtek-forum-168/

need RX7 02-01-10 01:03 AM

What are you needing to know? A standalone ECU completely replaces the stock ECU, and puts control of all the engine functions into the user's hands. Required for cars that have undergone extensive modding and have different fueling and ignition needs (big turbo conversion, radical porting, etc).

It is very important to have a professional tuner dial in all the settings on a dyno.

I suggest browsing this section to get an idea of what's out there, and who likes what for what reason, and what works best for this and that.

Aaron Cake 02-01-10 09:47 AM

Your question is very vague. Do you want to know what a standalone is? Specifications of each one? How to wire one? What they do?

Standalones have a steep learning curve, so starting with specific questions will get you better answers.

One thing that may help is my Megasquirt writeup:
http://www.aaroncake.net/rx-7/megasquirt

It covers a full Megasquirt install on a 2nd gen, and has a lot of standalone and EFI info thrown in as well.

PvillKnight7 02-01-10 09:53 AM

I hope you can read wire diagrams and solder correctly. Here is an example of a Haltech installation:
http://www.fd3s.net/haltech_install.html

RotaryEvolution 02-01-10 10:19 AM

timing maps are the most important, you have to get a decent map for the type of turbo and portwork you have done on your engine. learning fuel is fairly easy and simple if you follow a few guidelines and remember to work your way from rich to lean.

i recall some guys saying that running too rich can pop an engine, i laughed. you have to seriously be trying to and pushing quite a bit of power to do so.

ineedfc 02-01-10 12:35 PM

i was asking how to map it haha which im guessing is pretty difficult so like i said probably best to have someone teach me in person

Aaron Cake 02-01-10 01:15 PM

My Megasquirt writeup actually has a little section at the end called "basic tuning". This may help with your question a little.

RotaryEvolution 02-01-10 03:10 PM

yep, you will have to do some research or have a professional tuner show you in person. seeing some standalones with up to 4000 cells to adjust can be quite intimidating, especially if you have to adjust them one by one like the Rtek 2.0, which is why i really am not a fan of it. 10's of thousands of clicks? no thanks, i have better things to do with my time.

patman 02-01-10 04:32 PM

the first thing is to understand how the ECU works (all of them not just standalones, but standalones let you adjust).

Your ECU calculates fueling and ignition advance based on an equation that references tabular values.

In speed density (MAP sensor) form, it reads RPM and MAP, and uses this to look up the fueling values in a table. These are your base maps, which are what you typically spend the most time tuning. Values on this map are defined by the performance of your engine at that particular point, and depending on the ECU are expressed as milliseconds of injector open time, injector duty cycle, or volumetric efficiency. This value is then fed through a series of multipleirs, most of which are based on temperature. This is a separate set of maps which are usually expressed as a percentage. Typically you have more than one, ie coolant temperature and intake air temperature. These tables should be tuned such that the modifier is null (ie 100%) at normal operating condition (ie 180*F coolant temp) Any additional modifier tables are assessed, such as throttle position related ones, and the resulting value is converted into an injector pulsewidth (amount of time the injector is open, which determines amount of fuel injected per stroke.

Ignition advance is basically the same process.

This is a bit of a cumbersome explanation so here is an example:

Your ECU reads the sensors and sees 3000RPM, 2psi boost, 80C coolant temp, 35C intake temp, 100% throttle position.

It will go to the cell on your base map for 3000RPM and 2PSI, and take that value. For simplicity we will assume an ECU that uses injector ms (Microtech for example), so lets say that value is 5ms. It will store 5ms, then go to your temperature correction table and find the multiplier. Say your 'normal; coolant temperature is 90C, then this value will be a slight enrichment, say +5%, so your ECU now stores 5.25ms. 35C intake is a little warm, so typically you will add a little fuel for this, say another 5%, making it now ~5.5ms. 100% throttle generally means another enrichment, say another 10%, so your final injector pulsewidth will be ~6ms. Which is then produced by the computer, amplified, and sent to the injectors.
Note that this is a bit simplified as there are often more modifiers, and some are also scaled by a certain factor that determines how much an adjustment effects actual quantity of fuel.

Tuning involves first borrowing or calculating a set of basic maps that is close enough to make the car run. Then using a wideband and a set of experiments such as warmup sweeps and dyno pulls, you adjust the values in these maps to produce the desired AFR at each point that gives you the appropriate tradeoff between power and reliability. Typically ECUs have datalogging capability that assists with this process.

Ignition is much the same thing, although it is often 'guessed' more than tuned as the appropriate way to tune ignition is using cylinder pressure measurements which require relatively expensive equipment and machining.

There is a certain amount of compromise room between optimal ignition tuning vs fuel tuning, in other words you can run a 'safe' ignition advance curve and then tune fuel to make near optimal power, which is what most people do.

Most ECUs also have tuning tools such as master scaling (adjusts fueling by a percentage across the board) and aux input adjustments (nitrous enrichment trigger for example). There are also often sensor curves that can be edited and various calibration and setup values. Rotary mode in many ECUs, for example, adds a timing split map and an injection timing map for sequential injection.

OEM ECUs do this same thing, although the tuning is generally based on many more parameters and optimized for things like emissions and not necessarily peak power. I did some engine development on a diesel engine a couple of years ago that had something like 80 input channels that were used to calculate the fueling

RotaryEvolution 02-01-10 04:47 PM

80? pfft, i bet it barely ran cleaner than if you had 5. :)

ineedfc 02-01-10 05:49 PM


Originally Posted by patman (Post 9776740)
the first thing is to understand how the ECU works (all of them not just standalones, but standalones let you adjust).

Your ECU calculates fueling and ignition advance based on an equation that references tabular values.

In speed density (MAP sensor) form, it reads RPM and MAP, and uses this to look up the fueling values in a table. These are your base maps, which are what you typically spend the most time tuning. Values on this map are defined by the performance of your engine at that particular point, and depending on the ECU are expressed as milliseconds of injector open time, injector duty cycle, or volumetric efficiency. This value is then fed through a series of multipleirs, most of which are based on temperature. This is a separate set of maps which are usually expressed as a percentage. Typically you have more than one, ie coolant temperature and intake air temperature. These tables should be tuned such that the modifier is null (ie 100%) at normal operating condition (ie 180*F coolant temp) Any additional modifier tables are assessed, such as throttle position related ones, and the resulting value is converted into an injector pulsewidth (amount of time the injector is open, which determines amount of fuel injected per stroke.

Ignition advance is basically the same process.

This is a bit of a cumbersome explanation so here is an example:

Your ECU reads the sensors and sees 3000RPM, 2psi boost, 80C coolant temp, 35C intake temp, 100% throttle position.

It will go to the cell on your base map for 3000RPM and 2PSI, and take that value. For simplicity we will assume an ECU that uses injector ms (Microtech for example), so lets say that value is 5ms. It will store 5ms, then go to your temperature correction table and find the multiplier. Say your 'normal; coolant temperature is 90C, then this value will be a slight enrichment, say +5%, so your ECU now stores 5.25ms. 35C intake is a little warm, so typically you will add a little fuel for this, say another 5%, making it now ~5.5ms. 100% throttle generally means another enrichment, say another 10%, so your final injector pulsewidth will be ~6ms. Which is then produced by the computer, amplified, and sent to the injectors.
Note that this is a bit simplified as there are often more modifiers, and some are also scaled by a certain factor that determines how much an adjustment effects actual quantity of fuel.

Tuning involves first borrowing or calculating a set of basic maps that is close enough to make the car run. Then using a wideband and a set of experiments such as warmup sweeps and dyno pulls, you adjust the values in these maps to produce the desired AFR at each point that gives you the appropriate tradeoff between power and reliability. Typically ECUs have datalogging capability that assists with this process.

Ignition is much the same thing, although it is often 'guessed' more than tuned as the appropriate way to tune ignition is using cylinder pressure measurements which require relatively expensive equipment and machining.

There is a certain amount of compromise room between optimal ignition tuning vs fuel tuning, in other words you can run a 'safe' ignition advance curve and then tune fuel to make near optimal power, which is what most people do.

Most ECUs also have tuning tools such as master scaling (adjusts fueling by a percentage across the board) and aux input adjustments (nitrous enrichment trigger for example). There are also often sensor curves that can be edited and various calibration and setup values. Rotary mode in many ECUs, for example, adds a timing split map and an injection timing map for sequential injection.

OEM ECUs do this same thing, although the tuning is generally based on many more parameters and optimized for things like emissions and not necessarily peak power. I did some engine development on a diesel engine a couple of years ago that had something like 80 input channels that were used to calculate the fueling

excellent writeup thank you:icon_tup:


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