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Technical Couple of Quick Questions

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Technical Couple of Quick Questions

Any Wideband worth its salt will have more than one output and those outputs will all be adjustable.


A typical wideband will run at 0-5V, yeah, but you could run them anywhere in between.

You can also use a wideband output to simulate a narrowband (0-1V, and spevific AFR range). For example, on your tub, you can fit, say an LC1, remove the current narrowband entirely, use one output to replace the narrowband signal, and use the other output to drive a wideband gauge at full resolution of 0-5V.


The afr's that the voltage represents can also be adjusted.



the TPS has an earth, a 5v reference, and a signal line. The signal will be between 0-5V . it may not go all the way to 0v though or all the way up to 5v, i know both my cento, and my current rover tps don't. the rover tps has far greater resolution though ( more of a voltage variation from closed to WOT) :)


The ECU in the cinq's doesn't know engine speed at all :D its totally blind to it. Same with the sei's, even the mpi.

//edit - they know the engine speed (rpm) - not the car speed - silly me :D


Kristian
 
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No the rpm input comes from the CPS/VR/Crank sensor.


This generates an AC voltage for each tooth on the 60-2 wheel that passes under it.


At low rpm the crank sensor voltage will be only a few volts. At high rpm, it can be up to 50V AC!!!!!!!


This signal is interfaced bofore the ECU controller (but still in the ecu casing) and converted into DC logic.


RPM output for the tach on the cento is a seperate output from the ECU after it has calculated the rpm from the VR circuit. Not sure on what this signal is, I think its a PWM signal but not 100%

Kristian
 
OK thanks I think that's it for now, the MF2 i'm sure uses this, if I have problems with the ECU rev counter output and it is expecting a bigger voltage ie the Crank then i can always swop it .

By the way i'm looking at an electronic boost controler, I have been offered a Greddy Profec e-01 at a very good price brand new and still boxed never fitted and this looks and reads like the dogs danglies :cool: so I was just checking that i could get everthing on it to work before I continued negotiations.
 
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Dont know what that CPS system you have there is, but the Fiats I get a look at have 60 teeth with 2 missing teeth. The o/p from sensor is 2 opposite phase ac signals which go into a comparator circuit, when the voltages cross over a pulse is detected. When a series of 60 pulses is followed by the 2 tooth gap the ecu generates the timing pulse. The ac o/p is low for lo speed and high at hi speed, but its the crossover which is the important thing.
No value is taken from the ac voltage to calculate engine speed.
 
Greddy Profec, very nice bit of kit, if we had ever kept the Cinq that was our next port of call, electronic boost controller. As we found the boost tails off higher rpm, so with EBC on it you could hold say 0.6bar boost to red line if its safe and get way more power from the car, it has untapped potential.

Even had where I was going to put it thought out, so seeing as we no longer have one I'll let you know what my thoughts were.

I was going to remove the clock on the Cinqs dash as it leaves a rather convenient easily reachable and in perfect view position on the dash and the Profec B the one I was looking at is near enough perfect size (I got measurements from somewhere), so will look like its always meant to be. It was either that or going to Turbo Smart 52mm gauge sized controller which would then replace the boost gauge as well as a controller it is a gauge. once you remove the clock assembly there is loads of space behind dash, just need to make up a bracket to hold it in place.

Your car has a 2nd lambda boss on it as well as Jon got one welded in place in his work for rolling road purposes.
 
well the plan is at the moment to basically use this as a high tech early warning system and data logger as well as boost controler and to be honest i'll maybe reduce the boost a wee bit from where it is now :eek: as I'm not sure what effect the bigger TB has had if any on top end fueling (I certainly noticed a gain in manifold pressure once it was fitted)

Then on our cento rolling road day, i'll dial the boost up again and get the fueling checked with nice stable boost then bobs your uncle (y)

anything more than that is a pipe dream at the moment as once this is done it is back to preping and fitting the abarth kit
 
aah get you now(y)

Thought you were on about the piggy back idea and dumping the MF2

Well after searching some US sites and with the great US dollar exchange rates at the minute it's not as expensive as i thought just to do the injector contolling

Ah well it's only money...........sits and opens another beer
 
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