Just been out and really played with datascan...everything seems ok the only thing im worried about is duty cycle which went to 93 on a heavy accelerate on full throttle, though the af ratio did stay at rich through that, and my timing at the same point dropped to 18 degrees, though at 140mph it was fine at 21 degrees and the duty cycle went down a bit as well.

 

anyone shed any light on wether this means there is a prob or not.

what boost are you running? could have got Det and hence the timing retard, and the injectors defo running at full whack! - AF on datascan isnt a good indicator, you really need a wideband to do it accurately. at 140 you probably had less load on the engine as you would when planting through the gears, hence the normal readings.

you know what im a plonker, just been looking at the graphs and the retard is happening at gearchange ( mine is a auto ), running 12psi boost, they do retard ig timing to change gear dont they?

yup, think its about 10 - 15 deg's during heavy acceleration between the shifts on the autobox IIRC

did you say the timing dropped to 18degrees.thats advancing surely.

did you say the timing dropped to 18degrees.thats advancing surely.

 

no, it dropped to 18 degrees when he was at a higher rpm. Its 15 degrees only at idle.

 

The autobox retards timing on gearchanges to make the change smoother.

I always thought that the higher the number the more advance...considering on hard accel i usually get 21 degrees advance i was worried at the 18 which i classed as retard for gear change. now all i have to worry about is my duty cycle, i believe the datascan shows the figure in a percentage fashion so 93% is leaving feck all dead time...anyone know what the 100% timings are on standard injectors as in milliseconds so i can work out the dead time that it has.