what AFR

[JONNY172]

anyone any idea what AFR i should be seeing on my mk2 172???

i was thinking of putting the wideband on after the de cat to see what its fueling like but not sure what figures i should be seeing from my clio!

anyone any ideas?

 

[wide]

i think its around 14 but i might be wrong.

 

[Martin]

14-15 on mine...

 

[Fred@BTM]

search google for stoichiometric

 

[BenR]

depends what afr and load you are at.

crusing should be lambda 1 or 14.7AFR for petrol.

put it before the cat not after.

 

[JONNY172]

thanks for the replies guys, i was thinking at full throttle as i don't want it running too lean before i get it mapped.

i am using an LM-1 so it shows both lambda and AFR.

 

[stan*]

around lambda=0.88 for full load

 

[GordonD]

anyone any idea what AFR i should be seeing on my mk2 172???

i was thinking of putting the wideband on after the de cat to see what its fueling like but not sure what figures i should be seeing from my clio!

anyone any ideas?

Stoichiometric (14.7:1) is the theoretical right answer.

But in reality that's what you get best fuel economy at.

If you want best power you find you have to run a significantly lower number than that.

So you should be seeing 14s at cruising revs, but numbers down in the 12s at the throttle openings and the revs you use just in bursts for maximum acceleration.

 

[stan*]

14.7:1 is the theoretical right answer for part load only.

For full power and load you should expect an AFR of 12.5-13:1 on NA.

Cruising you could be running 15:1 for economy.

 

[JONNY172]

thanks Gordon and Stan, thats what i was looking for.

i was running 11.2 with my subaru and have only messed around with turbo motors in the past so this is all new to me

thanks again.