e-test trick - Page 2 - #1 Car Club In Kitchener - Waterloo - Cambridge

**Opel_Driver** · 01-25-2007, 11:40 AM

i don't remember you telling me joey, but you might have and it just slipped my mind. i do that a lot, hah.

timing is when the spark plug ignites in relation to where the piston is in its stroke. earlier will ignite while the piston has a lot of distance to travel upwards so the gasses are expanding while the piston is trying to compress them. this creates a lot of pressure and heat, and generally makes more power unless its too advanced. advanced timing usually has a more complete burn (hence why my HC, or hydrocarbons was low when my timing was advanced). retarded timing has less pressure and heat, less power. you adjust it by loosening the screws/bolts that hold your distributor to your head, then turn it.

**mx6onpsi** · 01-25-2007, 11:46 AM

I doubt itd be that easy to adjust on your car dbresha.

on older cars we have a distributor, how it works is there is a spinning metal that contacts with another metal, when you turn the distrubutor cap, it changes the time the two metal bits will come into contact with each other, thus changing when the spark will happen, thus changing the time of the detonation of the air/fuel mix in the combustion chamber. advanced means there will be more power because the detnoation will happen as close to top dead centre, however if its too far advanced the spark will go off too close to top dead centre (this is pre detonation) and this causes a lot of heat and additional wear and tear because the piston coming up has to fight the combustion before it goes back down.

retarding the timing makes it spark later, almost to make the combustion while the piston is on the way back down, less heat, less wear and tear and the result is less power.

NOx is a by product of high combustion temps, which is what this car was failing so badly. so retarding the times cools the combustion thus lowering knocks, however there is less heat so not everything is combusted in the cylinder, which will result in unburnt fuel and you will have higher HC on an etest (hydro carbon)'

hope that explains, i'd have to type so much to fully explain it but i'd think that would help you get a general idea

*edit* oh, it appears weve said the same thing again, why do we always do that.

01-25-2007, 11:40 AM	#26 (permalink)
Opel_Driver VM Member Posts: 2,761 Location: London & K/W Join Date: Apr 2005 Ride: '95 Civic Sedan Fav Mod: enjoying the stockness. Class: Street	i don't remember you telling me joey, but you might have and it just slipped my mind. i do that a lot, hah. timing is when the spark plug ignites in relation to where the piston is in its stroke. earlier will ignite while the piston has a lot of distance to travel upwards so the gasses are expanding while the piston is trying to compress them. this creates a lot of pressure and heat, and generally makes more power unless its too advanced. advanced timing usually has a more complete burn (hence why my HC, or hydrocarbons was low when my timing was advanced). retarded timing has less pressure and heat, less power. you adjust it by loosening the screws/bolts that hold your distributor to your head, then turn it. ------------------ Brendan: Bunch of 240s Some Opels And a Honda

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01-25-2007, 11:46 AM	#27 (permalink)
mx6onpsi VM Member Posts: 674 Join Date: Jan 2007 Ride: 1990 MX-6 GT Fav Mod: 3" side exit Class: Street	I doubt itd be that easy to adjust on your car dbresha. on older cars we have a distributor, how it works is there is a spinning metal that contacts with another metal, when you turn the distrubutor cap, it changes the time the two metal bits will come into contact with each other, thus changing when the spark will happen, thus changing the time of the detonation of the air/fuel mix in the combustion chamber. advanced means there will be more power because the detnoation will happen as close to top dead centre, however if its too far advanced the spark will go off too close to top dead centre (this is pre detonation) and this causes a lot of heat and additional wear and tear because the piston coming up has to fight the combustion before it goes back down. retarding the timing makes it spark later, almost to make the combustion while the piston is on the way back down, less heat, less wear and tear and the result is less power. NOx is a by product of high combustion temps, which is what this car was failing so badly. so retarding the times cools the combustion thus lowering knocks, however there is less heat so not everything is combusted in the cylinder, which will result in unburnt fuel and you will have higher HC on an etest (hydro carbon)' hope that explains, i'd have to type so much to fully explain it but i'd think that would help you get a general idea edit oh, it appears weve said the same thing again, why do we always do that.