Solder or Solderless? Question on ECU Tuning from Factory as Well

[Nismo_Freak]

What is the amount of voltage signal differentiation for a soldered wiring joint vs. using a custom harness connector?

Are the ECU's tuned from the factory using the OEM harness or do they tune the ECU's on a computer using just sensor inputs.

Reason being is that if one were to make a completely solderless wiring harness using connectors and bigger gauge wiring you would see a difference in signal would you not? Due to the thicker gauge causing less voltage drop in the signal, better grounding (for questionable grounds), and an overall increase in power delivery to the sensors.

Would such a change cause the engine to run better or worse? I guess the question there lies in how the ECU was tuned from the factory. If it was tuned on a computer then using a shortened, lower gauge, harness would be ideal, but if it were tuned from the passanger seat then it would be counterproductive as a small fluctuation in MAF, Coolant Temp, TPS, or 02 signal would be enough to change placement on the ignition and fuel maps.

[EZcheese15]

I don't think voltage drop across a connection is the problem, I think the connection is the problem. I always solder any connections I do that are ECU related. I've tried crimping them before, and 9/10 times, you get one bad connection and you can never figure out which wire it is (especially when you did a ton of them).

A good solder is a much more secure connection than a crimp. And when you are dealing with engine controls, fuel maps, etc, you don't want a bad signal. A stereo system is a different story, as the results of a loose connection are not nearly as severe. A bad connection on an ECU wire could cause you to blow a motor, depending on what wire it is.

Wire size can also play a factor in it, but for most ECU stuff, the added length of wire by an aftermarket control or sensor is usually neglagable. As long as you don't use a higher AWG of wire than what you are connecting, you should be fine. The big difference on wire AWG is seen with stereo equipment and batteries, where a large amperage is required to power the equipment. Voltage shouldn't drop through a wire, it's amperage that drops.

[qship96]

voltage does drop through a wire that is too long for its size,and as voltage drops,amp draw increases

[EZcheese15]

Thanks for the correction!

[Nismo_Freak]

Thanks for the correction!

Yeah thats my main reason for not relocating the battery

BTW, crimping is not something I would consider for an engine sensor. Stereo and other wiring.. yes.

I am talking about buying universal connectors (like the plugs on the harness now) and pin-out the swap wires to mesh correctly using no solder.

[Q45tech]

Other than the MAF, O2, and coolant temp sensor exactness of voltages don't matter as TPS is divided into 10 steps . Even CAS is reamplified and pulse shaped to square them.

[PoorManQ45]

A good solder is a much more secure connection than a crimp. And when you are dealing with engine controls, fuel maps, etc, you don't want a bad signal.... A bad connection on an ECU wire could cause you to blow a motor, depending on what wire it is.

^ this is very true. when you have to deliver an unaltered signal, always solder the connection points.

If you think about crimping the connections, try to use gold/silver connectors. As they offer a lower signal loss than copper connectors.

[Q45tech]

Again you show [PROVE] why you [poormanQ45] should not be posting in this forum!

"use gold/silver connectors. As they offer a lower signal loss than copper connectors."

Study the conductivity of annealed copper and GOLD/SILVER

PURE Silver while a 4% better conductor than copper cannot be used as the pure metal due to oxidation and amalgams and silver alloys have high resistances up to 40-70% worse than COPPER. Gold is 37% WORSE than COPPER.

http://www.ndt-ed.org/GeneralR...c.pdf

I am being intentionally hard on you so YOU will LEARN to research you facts prior to your post.............Here we are brutally truthful and stand no ignorance on the part of posters. ESPECIALLY when they post things that intentionally might mislead others!

Such is the rigor of engineering!

[Q45tech]

http://www.aimsolder.com/techa...s.pdf

[PoorManQ45]

I did not say annealed copper.

I was wrong about the gold being a better conductor.

But, I was right about silver being a better conductor than standard copper wire of the same diameter.

[PoorManQ45]

I do know what I'm talking about when it comes to metallurgy.

Silver has a rating of "105 IACS".

This is, of course, more conductive than annealed copper, which as you probably know has a rating of "100 IACS"

[EZcheese15]

The point of using a soldered connection vs. crimping is not because you get a weakened signal with crimping. It's because there is the possibility of getting NO signal with crimping.

Like Dennis said, voltage signals from an engine don't need to be exact. However, they *do* need to exist.

[DAEDALUS]

I do know what I'm talking about when it comes to metallurgy.

Silver has a rating of "105 IACS".

This is, of course, more conductive than annealed copper, which as you probably know has a rating of "100 IACS"

Remember that most of us don't live or drive in outer space. Just to be clear, you're recommending the use of pure silver connectors for a crimp application? Please satisfy my curiosity and direct me to a vendor who sells pure silver crimp connector leads.

[Q45tech]

Whether you crimp or solder you must consider the electomotive potential difference between the joining metals otherwise they will oxidize and create a non linear junction [corrosion] and act like a diode if the voltage and current are low enough.

Eutectic solder or 60% Tin/40% lead has the least difference in potential with copper.

Copper = +0.345 voltsTin = -0.136Lead= -0.126

Silver = +0.800Gold = +1.142 volts

It is not the absolute sign but the difference between metal that counts.

"The surface of any metal is a composite of a very large number of micro-electrodes. In order for corrosion to occur, the micro-cells must also be connected through some conducting path external to the metal. Usually the external connection is provided by water or an aqueous solution and the cells produce a current, allowing the chemical reactions responsible for corrosion to proceed."

IF YOU have to crimp a copper wire, a copper connector would be best.If you have to crimp a silver wire, a silver connector would be best.

I have tremendous experiences from another life soldering large hundreds of 1 foot wide 200 foot long copper straps and massive copper ground screens covering quarter acres together with real silver solder and 60/40 rosin core solders where the skin effect [where the signals travel on the outer electrons of the material] is critical in 50,000 watt AM broadcast stations in the 60's.

[PoorManQ45]

It is not the absolute sign but the difference between metal that counts.

I'm sorry, I completely forgot about the most important factor. Are the metals compatible.

I have tremendous experiences from another life soldering large hundreds of 1 foot wide 200 foot long copper straps and massive copper ground screens covering quarter acres together with real silver solder and 60/40 rosin core solders where the skin effect [where the signals travel on the outer electrons of the material] is critical in 50,000 watt AM broadcast stations in the 60's.

Wow. That is some serious stuff.

[PoorManQ45]

Remember that most of us don't live or drive in outer space.

Please stop insulting me. If anything, critize everything that I say.

Just to be clear, you're recommending the use of pure silver connectors for a crimp application? Please satisfy my curiosity and direct me to a vendor who sells pure silver crimp connector leads.

Actually, I was thinking more on the lines of pure silver wire. Connected my a pure silver solder. There probably is a company that sells pure silver crimp connectors. Q45Tech could probably direct you to one of them.

[Nismo_Freak]

I'm not talking about crimping, crimping was not part of my question at all.

I am thinking of this:

Making a complete shortened, rerouted OEM harness with minimized soldering (if not any) using off the shelf connectors to change the power wiring for the engine swap portion of the wiring.

A connector would be this:



Now... is there any benefit (other than I just wanna do it) in terms of engine signal performance by doing what I mentioned above?

[Q45tech]

I doubt it will improve anything as the engines are tuned over rich in acceleration.........more [higher] MAF voltage will just make it worse.......even 0.001 volt above the design numbers [1.2> 4.4 volts] will make it richer.

Same with TPS, etc.

All thermistors [coolant and air temp] are negative coefficient [ causing a higher temp reading with less resistance].

Even O2 are not sensitive to exact voltage as a mispoint of 0.4-0.6 volts is ok as long as the less than vs greater than midpoint switching occurs......anything from 0.65-0.99 volts or 0.1-0.35 volts is ok.

The engineers designed the signals [as received by ecu] to be tolerant of a little corrosion which might decrease the voltages by 10-20%.

Critical signals like crank position are backed up for safety and regenerated to square up the pulses so that the ecu can maintain timing to beyond 7,300 rpm.

[DAEDALUS]

Regarding soldering, I was talking with an instructor who is a former tech and who currently works the electrical side of things on a couple local race teams. He says pins are never soldered because of the induced hardening, which makes the connection susceptible to fatigue.

[s13sr20chris]

i kind of like the idea of a spade terminal panel. all spade terminals means bulky but easy to work with. i believe the mclaren F1 was designed that way.[crap im not sure about that]

[Nismo_Freak]

I doubt it will improve anything as the engines are tuned over rich in acceleration.........more [higher] MAF voltage will just make it worse.......even 0.001 volt above the design numbers [1.2> 4.4 volts] will make it richer.

Same with TPS, etc.

All thermistors [coolant and air temp] are negative coefficient [ causing a higher temp reading with less resistance].

Even O2 are not sensitive to exact voltage as a mispoint of 0.4-0.6 volts is ok as long as the less than vs greater than midpoint switching occurs......anything from 0.65-0.99 volts or 0.1-0.35 volts is ok.

The engineers designed the signals [as received by ecu] to be tolerant of a little corrosion which might decrease the voltages by 10-20%.

Critical signals like crank position are backed up for safety and regenerated to square up the pulses so that the ecu can maintain timing to beyond 7,300 rpm.

Guess it doesn't matter after all... just suffered an oil pump failure and will be rebuilding the engine. I will just move to a custom wiring harness and a Motec M4 engine management system.