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Discussion Starter #1
need to know if anybody has a good sample fuel Map using this ECU, Omex 600.

installed in in my 1971 GTV with Alfa Romeo twin spark 8v, modified with 10.5 compression JE pistons and Carillo rods and also using Jenvey 45 Throttle bodies
http://www.jenvey.co.uk/products2/twin-throttle-bodies/dcoe-throttle-body-118mm-long/tb-body-45mm-pair-tbp45i

current fuel map I have somewhat ok but too rich, i smell fuel all the time and bogs down at top and also not starting when cold, once its warm it will start with no poblems.

I have also added idle bypass so it iddles great but doesn't start when cold.

I have not found anybody in colorado springs that will dyno tune with this ECU.

I'll post some pics of the car and engine bay

let me know if anybody has a good sample fuel Map. I got the initial ignition MAP from Alfaholics when I bought the ECU which was working great with dual 45 Webers but decided to get these Jenvey's and having hard time getting it to work similar with good torque when I need it.

andre
 

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Start by installing a decent wide band air/fuel ratio meter after the last collector in the exhaust (not some stupid tailpipe installation).
Make sure you have a decent calibration curves in the ECU for the inlet air and coolant temperature sensors.
How are you sensing load?
Does the Omex do autotune for fuel? In this day and age it should.
 

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Discussion Starter #5
Start by installing a decent wide band air/fuel ratio meter after the last collector in the exhaust (not some stupid tailpipe installation).
Make sure you have a decent calibration curves in the ECU for the inlet air and coolant temperature sensors.
How are you sensing load?
Does the Omex do autotune for fuel? In this day and age it should.
Duk,

thanks for your feedback.

do you know of a decent wide band air/fuel ratio meter? I think this is probably my problem along with coolant temp sensor, I found out I can't use the same temp sensor as the dash gauge sensor.

and also need to install air temp sensor which is not easy since I don't have a normal fuel filter, I am using vw single weber filters. so i'll work on fixing that.

In reference to question if Omex does auto tune for fuel, I think it does, i see an option for automapping which I will see if it works, but I am not sure if it will auto sense load which is one of the reasons I was asking if anyone has done this and has a fully tuned an mapped ECU that can share a screnshot of the fuel grid map, my current default startup calibration shows VE load kPa vs. RPM at max if 99.6 kPa and thinking this value needs to be higher if this is injector pressure. I am not sure if this is the fuel injector pressure or what that is. maybe I should have kept my webers but I think I am too far committed to get this working now that's kinda crippled.
1648521

with map above, its currently too rich I can smell it and no power above 4k RPMs.
 

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do you know of a decent wide band air/fuel ratio meter? I think this is probably my problem along with coolant temp sensor, I found out I can't use the same temp sensor as the dash gauge sensor.
I've used Innovate in the past, tho some people have said that the quality of their product has gone down hill in recent years. There are plenty of options now a days.
And yes, the ECU's coolant temperature sensor must be separate from the gauge sensor. Make sure you are able to calibrate it. Omex should be able to provide you with a calibration curve for common Bosch sensors.

and also need to install air temp sensor which is not easy since I don't have a normal fuel filter, I am using vw single weber filters. so i'll work on fixing that.
Yes it is very important for the fuel calculations and helpful to get the best from the ignition mapping.

In reference to question if Omex does auto tune for fuel, I think it does, i see an option for automapping which I will see if it works, but I am not sure if it will auto sense load which is one of the reasons I was asking if anyone has done this and has a fully tuned an mapped ECU that can share a screnshot of the fuel grid map, my current default startup calibration shows VE load kPa vs. RPM at max if 99.6 kPa and thinking this value needs to be higher if this is injector pressure. I am not sure if this is the fuel injector pressure or what that is. maybe I should have kept my webers but I think I am too far committed to get this working now that's kinda crippled.
View attachment 1648521
with map above, its currently too rich I can smell it and no power above 4k RPMs.
The "99.6kpa" refers to how much air pressure the ECU is measuring.
Basically 0kpa is a total vacuum and everything above that is pressure above a total vacuum, with 99.6kpa being up around atmospheric pressure. This is the Absolute pressure measuring approach and is where the acronym for M.A.P. sensor comes from: Manifold Absolute Pressure.

Are you using a MAP sensor to measure load?
My suspicion is that you aren't. And even if you are, ITB and MAP sensors aren't, from what I've read over the years, a real good pairing. Basically, even if you get a vacuum signal from each inlet port (after the butterfly valves), the vacuum signal is considerably lower. This lowers the sensors available resolution.
This typical approach is to measure load for ITB is to use the throttle position sensor (TPS) and implement barometric pressure compensation.

I had a bit of a look at the software and tuning manual.
They do certain thing differently to what I'm a use to (Adaptronic).
My suggestion is that you make sure your injector size and base fuel pressure numbers for the ECU are correct, you configure the ECU to TPS for load measuring/sensing.
Hopefully the basic fuel map the ECU generates is reasonable.
Then get those temperature sensors sorted and calibrated.
And then get a wide band air/fuel ratio meter. Well, you just need a controller and sensor as long as the controller delivers a 0-5 volt signal for the ECU to monitor.
 

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Discussion Starter #7
thanks for feedback, I do have the right calibration for bosch injector model already and using TPS for load measuring/sensing, I should be getting the snsors installed today and wideband o2 kit should arrive today, so I'll install it next couple days or weekend.
 

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Assuming there's not an Omex forum, I would recommend looking at Megasquirt documentation, forums, videos, etc. The ECUs are different, but the principles are the same. The Megamanual has a good tuning section you can reference.

Start with the basics. Make sure all your sensors working. Start with a simple configuration and change one configuration at a time. Logging is essential to see exactly what's happening with your tune and AFR. Also keep an eye on your plugs. Bad tunes can cause fouling which may mask improvements you've made with your settings.

Tuning EFI is hard stuff, especially if you're a noob. Having an active community to fall back on certainly helps.

Good luck Andre - it's a brutal learning curve!

Lawrence
 

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Discussion Starter #9
Lawrence, thanks for the note, I am in contact with Omex support but he can only advise so much. I got the sensors I needed to get installed, coolant temp seonsor, air temp sensor just need to make sure I have the right calibration for the AEM AFR I installed then will see if I can do it, it sure looks hard to get done, I'll keep looking for someone who can get it tuned. last fuel map I copied is my manual work just changing the fuel map numbers manually I am hoping the new sensors will help with logging and getting fuel map and ignition map tuned. if not I'll have to go back to webers
 

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Once you have your AFR meter and temperature sensors installed and calibrated, you'll have a lot more information about what is actually happening.
There's a brilliant saying that is so appropriate for tuning: 'Without data, all you have is an opinion.'

One of the best features that decent programmable computers can do, is auto-tune via the wideband AFR meter/sensor.
BUT(!), you need to have IAT sensor installed, calibrated and a correction map in the computer first.
Some systems are very effective. I was very happy with the autotune capabilities of the Trust Emanage Ultimate (an interceptor tuning device that worked with factory ECUs and would modify the injector signal to achieve fuel tuning) from the early-ish 2000s.
Fast forward 10-15 years and programmable ECUs should be just as good and probably significantly better.

Autotune for the fuel map won't be the complete answer, but it will certainly give you a strong base to start from.
 
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