First off - we have it to where it accelerates fairly well without stumbling, however if stopped in gear and we crack the throttle it will stall and nothing we have changed seems to fix it.
Even tho it seems to be running ok otherwise, I still really have no idea how to use the Accel Wizard. For one thing the example image in the guide is old... It uses v/s as opposed to %/s so I'm not sure around what values I should be using.
Which values relate to tps and which ones relate to map. I don't really understand what the accel time and accel taper do.
Lot of questions sorry. Thanks for any info!
AE wizard - confused
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Read the manual to see if your question is answered there before posting. If you have questions about MS1/Extra or MS2/Extra or other non-B&G code configuration or tuning, please post them at http://www.msextra.com The full forum rules are here: Forum Rules, be sure to read them all regularly.
Forum rules
Read the manual to see if your question is answered there before posting. If you have questions about MS1/Extra or MS2/Extra or other non-B&G code configuration or tuning, please post them at http://www.msextra.com The full forum rules are here: Forum Rules, be sure to read them all regularly.
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m0ntecarloss
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AE wizard - confused
-- 86 monte carlo, vortec 355 xe268 cam, World Class T5, hedman headers with pypes x-pipe true dual exhaust system, still carbed NEEDS megasquirt bad 
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Bernard Fife
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m0ntecarloss,
The default values are a good place to start (especially if your req_fuel is somewhere between 10 and 20 milliseconds). To convert v/s to %/s, assume that 0%=0 Volts and 100% = 5 Volts (which isn't quite true, but it is a start), then 1.0 v/s = 20 %/s, etc.
The values on the upper right are the TPS based values (as noted by the heading above them), those on the upper left are the MAP based values.
The two vertical columns show the current TPSdot and MAPdot values, with the recent peaks 'tell-taled' in red.
Larger values in the "Value (ms)" entries increase the amount of accel enrichment. Smaller values decrease the amount of accel enrichment.
The slider chooses the percentage of MAP versus TPS, somewhere between 30% and 60% is good for most installations.
The accel time is roughly the equivalent of the old accel time (it is the duration, in seconds, that the full accel enrichment is applied), the accel taper time allows you to have the accel enrichment taper from the set value to the end pulse width gradually, rather than having the accel enrichment end abruptly.
Lance.
The default values are a good place to start (especially if your req_fuel is somewhere between 10 and 20 milliseconds). To convert v/s to %/s, assume that 0%=0 Volts and 100% = 5 Volts (which isn't quite true, but it is a start), then 1.0 v/s = 20 %/s, etc.
The values on the upper right are the TPS based values (as noted by the heading above them), those on the upper left are the MAP based values.
The two vertical columns show the current TPSdot and MAPdot values, with the recent peaks 'tell-taled' in red.
Larger values in the "Value (ms)" entries increase the amount of accel enrichment. Smaller values decrease the amount of accel enrichment.
The slider chooses the percentage of MAP versus TPS, somewhere between 30% and 60% is good for most installations.
The accel time is roughly the equivalent of the old accel time (it is the duration, in seconds, that the full accel enrichment is applied), the accel taper time allows you to have the accel enrichment taper from the set value to the end pulse width gradually, rather than having the accel enrichment end abruptly.
Lance.
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whittlebeast
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m0ntecarloss
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Great info, thanks Lance!
I have a couple more if you don't mind.
TPDdot Threshold means any value less than that doesn't count as accel right? So if you have a threshold of 20 say, and your lowest TPS-Based rate bin is 10 - then wouldn't that bin never get accessed?
Any thoughts on why it stalls if you tap the throttle quickly and let off while stopped in gear? The settings are not perfect but it doesn't stumble really when it accelerates...
I have a couple more if you don't mind.
TPDdot Threshold means any value less than that doesn't count as accel right? So if you have a threshold of 20 say, and your lowest TPS-Based rate bin is 10 - then wouldn't that bin never get accessed?
Any thoughts on why it stalls if you tap the throttle quickly and let off while stopped in gear? The settings are not perfect but it doesn't stumble really when it accelerates...
-- 86 monte carlo, vortec 355 xe268 cam, World Class T5, hedman headers with pypes x-pipe true dual exhaust system, still carbed NEEDS megasquirt bad
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Bernard Fife
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m0ntecarloss,TPDdot Threshold means any value less than that doesn't count as accel right? So if you have a threshold of 20 say, and your lowest TPS-Based rate bin is 10 - then wouldn't that bin never get accessed?
Not quite. It depends on the next higher bin. If the next bin is 20 %/s, then the first bin won't be used. But if the next bin is 40 %/s, the the value from 10 %/s to 40 %/s will be interpolated once the 20 %/s TPSdot threshold is reached. So the first bin doesn't come into play if the second bin is equal to or lower than the TPSdot threshold.
It could be that the decel amount is too low (or much less likely - too high). It could be that the accel erichment is still being applied, and flooding the engine (so keep the accel enrichment as short as possible - typically 0.2 to 0.5 seconds). It could also be that the ignition timing isn't right for high vacuums (which results from shutting the throttle rapidly) and low rpms. There are other potential causes as well...Any thoughts on why it stalls if you tap the throttle quickly and let off while stopped in gear? The settings are not perfect but it doesn't stumble really when it accelerates...
If you post a datalog, we might be able to comment more.
Lance.
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m0ntecarloss
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Well we haven't been able to play till today. Still can't sort it out -- tried playing with fuel and timing. Can't get rid of the stall when the throttle is blipped. Unfortunately the LC1 quit workin on us so I don't know how helpful the log is....lance wrote: If you post a datalog, we might be able to comment more.
Just look for where we blip the throttle... Tried to stall like 3 times and finally did on the 4th.
-- 86 monte carlo, vortec 355 xe268 cam, World Class T5, hedman headers with pypes x-pipe true dual exhaust system, still carbed NEEDS megasquirt bad
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Bernard Fife
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m0ntecarloss,
It looks from your datalog you you are only rarely getting any accel enrichment. So I think you need to lower your TPS dot threshold. I'm not sure what you have right now, but the lowest should be no more the 10%/s, I think. You could even try 7%/s.
What do you have in the 4 acccel bins? This is the next thing to mess with. If after decreasing the threshold you still have a stumble, then increase each of the bins by about 50% (if you have 1.6 in one bin, for example, increase it to 2.4), and let us know if that helps.
Lance.
It looks from your datalog you you are only rarely getting any accel enrichment. So I think you need to lower your TPS dot threshold. I'm not sure what you have right now, but the lowest should be no more the 10%/s, I think. You could even try 7%/s.
What do you have in the 4 acccel bins? This is the next thing to mess with. If after decreasing the threshold you still have a stumble, then increase each of the bins by about 50% (if you have 1.6 in one bin, for example, increase it to 2.4), and let us know if that helps.
Lance.