max timing for power
09-14-2005, 10:43 PM
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max timing for power after reading up i found people say 28* is optimal.
now- the map i was running i just added 2* through the powerband (rpm range and map. cells). i tried also running a straight flat 28* of timing through the powerband with the timing ramping up at 5k to 29* and 5600 to 31*. i get no kr with either way.
which is optimal? do i want the curve (in which the timing dips in the mid-range to around 26* and ramps up to 29* at 5600rpms) or the flat 28*?.
im good at tuning a/f ratio, been doing that for some time now and im happy with it. timing- well i thought you want as much as you can run without getting kr, but now after a search im reading too much timing can HURT power even if you are not getting kr, and im hazy on why the stock map has the timing dip in the mid-range then go back up in the upper rpms.
comments? timing curve or flat 28*?
any experienced help is much appreciated.
now- the map i was running i just added 2* through the powerband (rpm range and map. cells). i tried also running a straight flat 28* of timing through the powerband with the timing ramping up at 5k to 29* and 5600 to 31*. i get no kr with either way.
which is optimal? do i want the curve (in which the timing dips in the mid-range to around 26* and ramps up to 29* at 5600rpms) or the flat 28*?.
im good at tuning a/f ratio, been doing that for some time now and im happy with it. timing- well i thought you want as much as you can run without getting kr, but now after a search im reading too much timing can HURT power even if you are not getting kr, and im hazy on why the stock map has the timing dip in the mid-range then go back up in the upper rpms.
comments? timing curve or flat 28*?
any experienced help is much appreciated.
09-14-2005, 11:04 PM
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I've always run it on a curve. I have mine kind of aggressive down low(26-29*) and then as I come up on peak tq I peel back the timing to around 25* or so and feed it back after peak tq up to peak hp. Kind of mimics my tq curve upside down.
09-15-2005, 04:56 PM
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Yeah, the cyl. pressures follow the tq curve so that's why the timing is kinda opposite. You can't have as much timing at pk tq b/c the cylinder pressures are higher.
09-15-2005, 06:23 PM
#5
also other things to consider are that you dont always need to make 30* to get max power..some cars do way better at 26* or even as low as 22*
It really depends on so many variables..
the best way to find out is to hit a loaded dyno and play with the spark..moving just a little at a time till it stops making power....
then do your low octane tables at -4 from those values
also If you increas spark dwell(playing with this right now myself) and get a gain of power with not as much timing..
I have a spark dwell tabel that I have done(thanks to wait4me) thats seems to have netted a few extra ponies on a few cars.... its usually only about 2-4hp...but hey...dyno queens look for any power they can get...
on the strip its not even realy noticeable...but I have been able to feel a slight difference on normal everyday driving
It really depends on so many variables..
the best way to find out is to hit a loaded dyno and play with the spark..moving just a little at a time till it stops making power....
then do your low octane tables at -4 from those values
also If you increas spark dwell(playing with this right now myself) and get a gain of power with not as much timing..
I have a spark dwell tabel that I have done(thanks to wait4me) thats seems to have netted a few extra ponies on a few cars.... its usually only about 2-4hp...but hey...dyno queens look for any power they can get...
on the strip its not even realy noticeable...but I have been able to feel a slight difference on normal everyday driving
