Lambda question??
Turbo Mini Forums

Is it okay to run a standard Metty Turbo engine without Lambda fitted?? And at what point when beginning to modify the engine should a Lambda kit be fitted??

Cheers
Rich

you can run one all day long without if you get it setup somewhere that sorts the fuelling properly. a lot of people do. But the setup is all important, even on a standard engine.

but then if you can fit one, why not. gives you a piece of mind

Cheers Iain

Just trying to prioritise funds at the moment and if I don't need one initially then that's more money towards more power!

yeah im after fitting one soon seems a real good idea

i have searched over the months for a decent unit and have found one which i will be purchacing shortley .....

T Dave place a link on another thread for the same gauge a while back just wondering does anyone know where there is the same gauge cheaper ???? may be in the UK??

the link below gives all the info
i think this is an excellent peice of kit but.... a touch pricey
http://www.prostreetonline.com/buy/aem_uego_controller/

Edited by BENROSS on 6th Jul, 2005.

not that bad really, under £200

thats really good and i have to say im tempted. Especially as i may know someone in the US to post it to then put in their suitcase

Not in the near future but certainly one to think about.

For now you can read the lambda with a multimeter, I did that on my TR. once the carbs and needles are set you dont really need it much.

My website at www.turbominis.com has a TR250 area and there is a description of what voltages to look for on a meter in the tech info page

Edited by Turbo Tel on 6th Jul, 2005.

website:- http://www.terryhunt.co.uk

anyone know what the wiring is on a 3 wire lambda this audi engine i bought for the golf still had the manifold and downpipe fitted with a bosch 3 wire lambda

Don't know the specific wires but 2 are for 12v heater and one carries the signal. get the signal ground from the casing. Use a meter from the case to each wire in turn and heat it with a propane torch. The one that gives you around 0.6-1.0 volts is the signal wire. Also a good way to test it for correct operation

1 wire sensors rely on heat from the engine so neeed to be fairly near the manifold, 3-5 wire sensors have a 12v heater and can be positioned further away from the manifold, they also come up to operation quicker. 4 wires are basically the same as 3 but have a seperate ground wire for the signal. 5 wire sensors are probably too fancy for mini's......

addition:found this in another thread. try www.lambdasensor.com It seems to have lots of wiring info.

Edited by Turbo Tel on 16th Aug, 2005.

website:- http://www.terryhunt.co.uk

Would it be possible to buy a Lambda with a LOONG lead so that you may fit it to the end pipe, and have the gauge inside the car? This way, the same gauge could easily be used on different cars, too keep costs down.
Like the ones used at MOT-centers. I've seen some people driving around in cars with a cable out of their exhaust.

5 wires are vital....

its not wide band unless it has 5.

Anything less is used to run a catalytic convert and nowt else.

Alex

AlexF

Narrow band is fine for most tuning that folks on here see, and tons better than trying to use a colourtune (do they still make them?), looking at plugs, or hit-and-miss alterations...
Narrow band needle tuning is all my mini has ever seen.
Thing is, most peeps still don't have a clue what to do with the output from the lambda other than the simplified phrase "file the needle" ...

I'm buying two AEM narrow-bands over winter however As I've said before, these are great as they have a digital display, but the sweeping analogue 'visual' indicator which your mind can read and interperet instantly (unlike sole digital readouts).

Oh, Vegard - what you're proposing is fine, but would need the four-wire (heated, with power and signal) type of lambda. Far better than having nothing.

I used narrow O2 sensors with a simple multimeter on my TR250 and found that it was good enough to get the mixture setting to within a "flat" on the jet, OK it was not a steady reading as the SU's just aint that good, but as good a basic setting as you will get from anything. it also gives you a good idea of the mixture on accelleration cruise etc. Playing with the basic setting and watching the results in accelleration/cruise can give you a better idea on the needle profile. Unless you are planning to grind your own needle I would agree that its fine.

As to the long leads into the exhaust, may work but the sensor may need a source of fresh air as well so shoving it up the pipe may not fly. I do remember seeing somewhere that you should crimp, not solder O2 leads as some use porous leads to supply the fresh air...could be worth looking into.

website:- http://www.terryhunt.co.uk

I've now got a wide band kit that can tell you almost exactly the difference beween 30:1 and 2:1 Air Fuel Ratios.

I also have a couple of cheap narrow band kits.

Narrow band is better than a color-tune (I believe they still make them Dave yes!!) but not by much.

Soon as the engine goes rich thats it.. it can't see the difference between 9:1 and 13:1

In terms of checking if you go lean its much the same.

Both the ones I have a pretty light! I wouldn't recomend anyone sets their car up SOLELY using one. IE Rolling Road or live map it.

Alex

AlexF

How much did the wide band cost??

website:- http://www.terryhunt.co.uk

I was guessing, from the website:

"The mapping is capable of 7.35 to 22.4 AFR. A range of 10-30 AFR would require significant changes in the software of the LM-1."

so I was a bit off... but its a bigger range than you need considering:

8:1 is about the limit for rich ignition
12.5:1 is where you want it
14.7:1 is stoich
18:1 is wayyyyyy lean (and about the limit before misfire)

Alex

AlexF

woweee! So it has the potential to do that though... Wonder what engine can be running that kinda range... Maybe it's to give scope for LPG or something? 8)

On a narrow band sensor:-

10:1 is 1.0 volts -- approaching the limit for rich ignition
12.5:1 is 0.87 volts --where you want it for max power
14.7:1 is 0.4 volts ---stoich
15:1 is 0.1 volts ---max mpg point and the lowest you want to see at any point.
18:1 is 0.05 volts --- about the limit before misfire

Wayyy better than a Gunsons, great for setting your idle mixture and good enough to get you down to the rolling road.

website:- http://www.terryhunt.co.uk

Its designed to work with:

Methanol
Diesel
LPG

and almost anything else!

Not sure how long the sensor will last with fuels other than petrol!

Tel,

You must have a better lambda sensor(s) than me! Mine are two different types but nither give you that resolution! One came with a car and one was borrowed from Ford...

Alex

AlexF

I was always lead to believe that USA spec lambda's were superior to the european versions, but could never find out any evidence. Maybe Tel has the proof right there?

This is like I've seen mostly: http://www.ntklambdasensors.co.uk/main/pic/graph.gif

All sensors are the same but when you use a good multimeter these subtle differences can be seen, don't get me wrong, the SU carb just isn't that accurate to give a steady reading but you can see it hover around the 0.87 volts (max power) on accelleration, make sure it never drops below 0.1 volts (too lean) and it will bounce around between about 0.2-0.7 when you have the idle smack on, one flat either way and you can see it get rich or lean and I recon one flat is about as accurate as you can get. I could even see the difference between a cold and hot day

What I did was find the idle spot and if e.g. the cruise was too lean I turned the jet 1 or 2 flats richer at a time till the cruise was about right, even if it swings from lean to rich you know how many "flats" you are out when it happens. then I did the same for full throttle which was rich, this time leaned it up a few flats and found the point at which it gets lean. My first 2 needles were miles out but eventually using the info from them I found one which was great at idle and cruise but was a flat or 2 rich at acceleration, I left it at that.
now if someone with a bit of maths could work out the jets height difference per flat we could use the needle profile to nail down the perfect grind...

website:- http://www.terryhunt.co.uk

flats?

Alex

AlexF

Su carb... Flats on the old HS series... No such thing on HIFs unfortunately.