Lancer Register Forum banner

1 - 11 of 11 Posts
G

·
Discussion Starter #1
Anybody here using this device (pen size turbo timer) to monitor your Air/Fuel ratio? Is this device accurate?

What are your typical/normal readings during idle, cruise and full throttle (WOT)?

Thanks!
 
G

·
Discussion Starter #2
Dunno never heard of it, Turbo Timer and A/F meter seems a funny combo? Then again an A/F meter is cheap enough to make. What does the scale consist of? Digital readout or lights?
At idle when the car is warm it should be about 14.7:1
I have just finished building my own A/F meter out of 21st C Performance, I will hopefully get around to testing it tommorrow ;)
 
G

·
Discussion Starter #3
Actually, at idle it should cycle quickly between 0.1v and 0.9v or so, or show the corresponding a/f ratios to these voltages. It will never give a fixed value at idle or cruise due to closed loop operation.
 
G

·
Discussion Starter #4
Quite right it will cycle up and down but the centre will average on 14.7:1, sorry should have made that clear.
 
G

·
Discussion Starter #5
Does this seem correct? My A/F readings shows the following:

A/F ratio 14.6 @ idle
about 15 @ 3,000
about 12 @ 5,000
about 10 @ 7,000 Wide open ........too rich maybe??

Any comments welcome! Cheers!
 
G

·
Discussion Starter #6
10:1 is quite rich but it is probably mapped this way for safety. ideally you would 11.1 is what you should be aiming for. but the other question that springs to mind is who accurate that A/F meter?

can you tell me where did you get it from and what it looks like? i am quite interested in getting a lambda display but they all look kind of ugly.

sam
 
G

·
Discussion Starter #8
Any a/f meter that takes readings from the stock lambda sensor will be
next to useless; the lamda sensor fitted to our cars is a narrow band sensor,
ie its only designed to work at low/medium throttle positions.

I hooked up an ultra wide band motec to mine (cost £2000) and it was bang on 12.1:1
on wide open throttle (until we fitted the HKS FCD which screwed up the mixture).

Blitz do now sell A/F ratio meters which have their own sensor and these have replaced
EGT gauges (Blitz have stopped making EGT gauges). Unfortunately, cost for such an
incredibly useful gauge with the sensor is £700|PLS| 8-(

Justin
 
G

·
Discussion Starter #9
hi justin
you are correct about the norraw band sensors. however although they don't read very accurately they can give you a good indication. the problem with a narrow band is that they heat up very quickly so you have to take that in mind when using it. i have used the standard lambda sensor in my subaru and it was only 1%co off at the top end, confirmed by gas analyser on a rollers.

i have also used the bosch lsm11 which is a very good sensor although it isn't a true wide band it is as close as you would get to it with out spending silly money.

basically if you read 8%co at the top end to is most likely you are runing 8.5-9% if you are using a narrow band.


all the above info is based from my experience with subarus however a car is a car and thing should not be that much different.


sam
 
G

·
Discussion Starter #10
hi Sam,

The A/F meter is made by Apexi. It's primary function is a turbo timer, voltmeter, O2 display and A/F ratio display.

The unit is very small and is pen shape. It's called ' Turbo auto timer' on the box.

bye
 
1 - 11 of 11 Posts
Top