Advance at idle

FazerBob · Post by **FazerBob** » Wed Apr 23, 2008 10:26 pm

I've used the basic map from the library for my 1.8 Zetec. The engine was very lumpy at idle so, after balancing the carbs, I started playing around with the advance figure, basically doing with a laptop what we used to do by loosening the distributor body and turning it forwards and back until we got the smoothest idle.
What I have found is that the smoothest idle on my engine is when the advance is set between 20 and 24 degrees.
Changing the advance to the more conventional settings of between 8 and 14 degrees results in a lumpy idle.

Questions:
Is the advance figure of circa 23 degrees acceptable, so leave it at that?
Am I likely to damage anything by having the advance set so high?
Should I return the timing to 12-15 degrees (as in the library maps) and put up with a rough idle?

Any answers?

Hedworx · Post by **Hedworx** » Wed May 21, 2008 8:36 pm

mine is the same (22degree for now) i used to run a fixed advance distributor at about 28 degrees and once the engine is past the cranking moment it will run fine.

keep in mind that the dizzy was set at half the crank degee setting (16 to 28 degrees)

FazerBob · Post by **FazerBob** » Wed May 21, 2008 9:32 pm

Hedworx wrote:mine is the same (22degree for now) i used to run a fixed advance distributor at about 28 degrees and once the engine is past the cranking moment it will run fine.

keep in mind that the dizzy was set at half the crank degee setting (16 to 28 degrees)

Thanks for the info - at least I know I'm not alone.

alfa boxer · Post by **alfa boxer** » Fri May 23, 2008 3:24 pm

Are you running carbs? i found on my own engine that my idle jets were too big so i was having to use a lot of advance to compensate! signs were- poor idle wery dark almost wet plugs .put smaller jets in and lowered the idle down to 9deg idles at 950/1050 happy days.hope this helps Lee

FazerBob · Post by **FazerBob** » Fri May 23, 2008 5:20 pm

alfa boxer wrote:Are you running carbs? i found on my own engine that my idle jets were too big so i was having to use a lot of advance to compensate! signs were- poor idle wery dark almost wet plugs .put smaller jets in and lowered the idle down to 9deg idles at 950/1050 happy days.hope this helps Lee

Thanks Lee, I'll check them out. They should be ok though as I'm running bike carbs from a 600cc Fazer, with the main jets drilled to 1.7mm.