Piggyback for combustion engines

[lilltroll]

Do we have any motor-heads here ?

Maybe not common in the UK, if you look at TopGear, but in other countries it common to mix an alcohol to the petrol - to use less oil.
Typically the octane rating increases so the compression is not an issue, but the energy/volume quotient will change, and in the end that needs to be compensated by the fuel injection.

If you have a car that isn't specially made for mixed fuels, the ECU will compensate with help of the readings from the lamda (stoichiometric air-to-fuel ratio) in steady state, but during other events it will use a look up table. That table will be incorrect with mixed fuels*.

A trick to is to hijack the signal to or from the ECU to change the timing of the fuel injection to improve the combustion without replacing the entire ECU.

An other thing is to avoid lean burning, since that might overheat engine parts. If you add fuel with less energy-density, the combustion process will have too little fuel, NOx will be created and the temp. will increase. Exhaust vales might be overheated during full acceleration.

In Sweden we have E85, thats about 85% of Ethanol.
The 95 octane gasoline is often mixed with 5% or 10% ethanol during the summer by the fuel company.
(It saves them money since ethanol is less taxed in Sweden - and thus cheaper to use/liter. Consumers pay per liter, not per energy unit)

The idea is to use an L1 as an piggyback, that also logs events to the flash-memory.
An event may be a dangerous lean conditions or a wastefully rich condition.
It will not measure the actual fuel with some hitech sensors - you have to input the mixture after fueling your car by hand.

*It might be slowly adapting over time

[waluigi]

I've got an XC-1A running my injection at the moment, trying to move the ignition over at the moment. Just a standard car, trying to get more control of the ECU.

I have been working on this for almost three years, so I'd say progress is slooowwww.

[nieuwhzn]

Just don't do it unless you're willing to sacrifice your car. The only proper way of doing this is by accessing the ECU code and change the maps, even that should be done with a lot of caution. A lean running engine will in the best case overheat your catalytic converter (i.e. destroying it), other damage includes, but is not limited to, burned exhaust valves, holes in pistons, etc.
If you really want to go this way then there are forums dedicated to reflashing the ECU. Trying to fool the ECU by massaging the inputs of the sensors is a bad idea, without proper testing equipment you will have no idea where you will end up in the maps.

[Berni]

Yeah its a better idea to reflash the ECU. People do it all the time to try and get some extra horses out of it. So a lot of car moding shops will be able to do it.

[lilltroll]

Not for everyone, I agree!

Anyone that can find the engine part/parts that became a "catastrophic failure" in this picture ??

Motorslakt.jpg

(134.73 KiB) Not downloaded yet

Motorslakt.jpg

(134.73 KiB) Not downloaded yet

This picture was not the end of the story - the car is on the street today.

It's not intended for supercharged or turbocharged ICE, that becomes to complicated.

[nieuwhzn]

Crankshaft bearings?

[lilltroll]

Crankshaft bearings?

Correct :D

The copper inside the bearings was found in the oil-pump ... and everywhere else :twisted:
The crankshaft was destroyed as well.

Someone had added new engine-oil only, instead of changing the oil :twisted: