timing and grams per cylinder
05-29-2006, 02:26 AM
#1
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timing and grams per cylinder would timing effect how deep you get in cyl- pressure table, like
not enough timing would result in less cyl -;pressure.
not enough timing would result in less cyl -;pressure.
05-29-2006, 02:23 PM
#4
i'd say yes it would.
timing affects effective compression, popularly referred to as torque.
dynamic cylinder fill describes how much air is in the cylinder, which is effective compression.
flamefront travels faster in more compressed gasses, shortening time needed for it to travel from the spark plug to the top of the cylinder. thus, more compression == less advance needed. in NA applications the differences are fairly subtle, until you get really crazy with static compression. in FI, you don't need much timing at all, as the compression is crazy by the very nature of FI.
timing, especially the ranges in which your usual NA LS1 operates might make not enough difference to be noticed by the dynamic cylinder fill PID, that's why it might not seem like it's doing much.
if you want, do an experiment, set wot timing to 19, do a run in one gear through the whole range. then change it to like 29 (or whatever else it can take safely) and do the same thing. compare the runs, and you should see enough of a difference to notice, both dyncylfil and time needed to traverse the same speed interval.
i've been doing a lot of research on it lately, so if you want to know more, aim me or something, i'm not quite done so i haven't posted anything yet, but it's enough to show you few important points.
timing affects effective compression, popularly referred to as torque.
dynamic cylinder fill describes how much air is in the cylinder, which is effective compression.
flamefront travels faster in more compressed gasses, shortening time needed for it to travel from the spark plug to the top of the cylinder. thus, more compression == less advance needed. in NA applications the differences are fairly subtle, until you get really crazy with static compression. in FI, you don't need much timing at all, as the compression is crazy by the very nature of FI.
timing, especially the ranges in which your usual NA LS1 operates might make not enough difference to be noticed by the dynamic cylinder fill PID, that's why it might not seem like it's doing much.
if you want, do an experiment, set wot timing to 19, do a run in one gear through the whole range. then change it to like 29 (or whatever else it can take safely) and do the same thing. compare the runs, and you should see enough of a difference to notice, both dyncylfil and time needed to traverse the same speed interval.
i've been doing a lot of research on it lately, so if you want to know more, aim me or something, i'm not quite done so i haven't posted anything yet, but it's enough to show you few important points.
05-30-2006, 06:49 AM
#5
TECH Fanatic
Hmm, its also possible that the lower timing will leave more residual gasses in the cylinder due to slower and later combustion meaning its too full to eat another mouthful and therefore results in less g/cyl of air.
