hi, Does any one know how this effects MOT? The emissions would be higher on carbs as its not computer controlled to high standards like the origonal EFI system so how do people get them through the MOT?
Cheers.
Running on carbs
Wouldn't you get a gas analyzer tester & probe. Then run the engine while you tweak the carbs to make the fuel less or more richer (until you get it right) then you will be greenhouse happy. Not sure what the spec would be though on emissions.
What most people do, is tune the carbs down before the MOT, then tune them back up after.
Best thing to do is ask a MOT center what the legal limit is, and if you can use there analyzer at there place for a fee.
What most people do, is tune the carbs down before the MOT, then tune them back up after.
Best thing to do is ask a MOT center what the legal limit is, and if you can use there analyzer at there place for a fee.
If you find out the limits could you post them please, only additional thing I can help whilst tuning using the gas analyzer is this little guide:
CO high, CO2 low, HC high, O2 high - rich mixture with ignition misfire
CO high, CO2 low, HC high, 02 low - faulty thermostat or coolant sensor
CO low, CO2 low, HC low, O2 high - exhaust leak after the cat
CO low, CO2 high, HC low, O2 high - injector misfire, cat OK
CO high, CO2 low, HC medium to low, O2 high - rich mixture
CO high, CO2 high, HC high, O2 high - injector misfire, cat not working, combination of rich mixture and vacuum leak
CO low, CO2 low, HC high, O2 high - ignition misfire, lean mixture, vac or air leak between air flow sensor and throttle body
CO low, CO2 high, HC low, O2 low - good AFR and cat operation - system normal
CO high, CO2 low, HC high, O2 high - rich mixture with ignition misfire
CO high, CO2 low, HC high, 02 low - faulty thermostat or coolant sensor
CO low, CO2 low, HC low, O2 high - exhaust leak after the cat
CO low, CO2 high, HC low, O2 high - injector misfire, cat OK
CO high, CO2 low, HC medium to low, O2 high - rich mixture
CO high, CO2 high, HC high, O2 high - injector misfire, cat not working, combination of rich mixture and vacuum leak
CO low, CO2 low, HC high, O2 high - ignition misfire, lean mixture, vac or air leak between air flow sensor and throttle body
CO low, CO2 high, HC low, O2 low - good AFR and cat operation - system normal
CO - carbon monoxide, poisonous gas aslo used to work out "air to fuel ratio". To much fuel causes high carbon monoxide readings.LeMeph wrote:Whats CO and HC? Assuming its a reference to some kind of compunmd. What compounds might they be?
CO2 - cabon dioxide, shows how much fuels been completly burnt
HC - hydrocarbons, as not all the fuel is burnt off, if high it means somthings playing up in terms of cumbustion or incomplete combustions.
O2 - oxygen, show either incomplete combustion or an air leak or Air to fuel ratio too weak
Who do they think they are! If i want oxygen coming out my zaust, i will have it! 
Ignore that outburst.
Right.. I will try to get the correct figures for this engine. Im not going to be ding the conversion untill i have a new engine block as my pistons broken
but when its sorted its having the full works.
Ignore that outburst.
Right.. I will try to get the correct figures for this engine. Im not going to be ding the conversion untill i have a new engine block as my pistons broken
but when its sorted its having the full works.