ok its time to see how mr mot man likes my mapping!

the st170 setup is fitted with the cat from the old 1.8 engine atm

i run the idle adjuster slightly open and retard the ignition to -5 degrees then below 800 rpm i have 15 degrees ignition advance because there isnt an idle control valve and no ignition based idle control in the software

what i was wondering is does retarded ignition cause changes to the emissions test even tho its mapped to a rock steady 1 lambda/14.7:1?

with the ignition at 10 degrees and the idle screw reduced it's crappy at parking and bogs down when the fans kick in or drag the clutch in a traffic jam

and yes the boddies have been ballenced!

so will the retarded ignition give me problems?
cheers

 

Any change of the timing will cause a effect of the mixture, the boggy nature suggests it is weak.
tabetha

 

Too retarded means the combustion process wont finish properly and this will effect your emissions.

What you need is a little less airflow and a little more ignition.

 

if i have the idle screw set at 800rpm and 10 degrees ignition it cant compensate for the fans kicking in because there isnt enough air going in to create torque for the alternator no matter how much ignition i add below 800rpm. its rearly easy to stall when setup like this

i dont have a problem with the 3000rpm test plenty if ignition and sits at 1 lambda niceley

i have to have plenty of air going in then counteract it with some retard (-5 degrees) then the site below 800rpm have lots of advance so it stops the engine going below 800rpm and prevents stalling so it behaves like it has an idle control valve

it works verry well like this but i'm unsure if it will cause a fail on the mot test

i suppose i'l take it as it is and see what happens and leave a bottle of scotch on the seat with the testers name on it