Any tips/tricks to getting nice MAF curve after VE?
05-11-2007, 09:40 AM
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Any tips/tricks to getting nice MAF curve after VE? I had this problem last year with HPT, where my VE would pretty much be dead on +/-2% error in all cells with a fairly smooth graph.
But my MAF tune afterwards (still in SD mode) would get some weird bumps along the graph. I would manually flatten, do another run, and boom, comes back again. This is using HPT's histograms.
How does everyone get thier plots very smooth with no bumps, but a nice exponential increase?
But my MAF tune afterwards (still in SD mode) would get some weird bumps along the graph. I would manually flatten, do another run, and boom, comes back again. This is using HPT's histograms.
How does everyone get thier plots very smooth with no bumps, but a nice exponential increase?
05-11-2007, 09:58 AM
#2
Originally Posted by SilverSmoke
But my MAF tune afterwards (still in SD mode) would get some weird bumps along the graph. I would manually flatten, do another run, and boom, comes back again. This is using HPT's histograms.
If you are in SD mode and tuning the MAF, the ECM will ignore the input from the MAF, you will be pretty much doing nothing. You need to re-enable the MAF and use the AFR Error % logged against the MAF Table, while logging MAF Hz. Or you could plot the Dyn Air against the MAF Table to shape your MAF Curve before you enable the MAF. Another thing is try using Marcin's (redhardsupra) MAF spreadsheet to curve the graph, works pretty good. What are you using to re-curve the MAF Table (ie: Wideband, Dynamic Airflow, LTFTs)? 
05-11-2007, 12:19 PM
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Originally Posted by 12secSS
Well hell, that's one good way of not getting in line. If you are in SD mode and tuning the MAF, the ECM will ignore the input from the MAF, you will be pretty much doing nothing. You need to re-enable the MAF and use the AFR Error % logged against the MAF Table, while logging MAF Hz. Or you could plot the Dyn Air against the MAF Table to shape your MAF Curve before you enable the MAF. Another thing is try using Marcin's (redhardsupra) MAF spreadsheet to curve the graph, works pretty good. What are you using to re-curve the MAF Table (ie: Wideband, Dynamic Airflow, LTFTs)?
If you are in SD mode and tuning the MAF, the ECM will ignore the input from the MAF, you will be pretty much doing nothing. You need to re-enable the MAF and use the AFR Error % logged against the MAF Table, while logging MAF Hz. Or you could plot the Dyn Air against the MAF Table to shape your MAF Curve before you enable the MAF. Another thing is try using Marcin's (redhardsupra) MAF spreadsheet to curve the graph, works pretty good. What are you using to re-curve the MAF Table (ie: Wideband, Dynamic Airflow, LTFTs)?I am using a WB to tune the car.
Hmm, will have to double check this in HPT. I think it will do dyn air, which is why I have the MAF still disabled. The MAF graph gets fairly solid, its just those areas of bumps or hills should call it that don't flow with the rest. But even if it is logging in hz, it is still an accurate number comming through, it's just that the computer is not using the information from the MAF since it is failed out.
05-11-2007, 01:22 PM
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Originally Posted by 12secSS
Well hell, that's one good way of not getting in line. If you are in SD mode and tuning the MAF, the ECM will ignore the input from the MAF, you will be pretty much doing nothing. You need to re-enable the MAF and use the AFR Error % logged against the MAF Table, while logging MAF Hz. Or you could plot the Dyn Air against the MAF Table to shape your MAF Curve before you enable the MAF. Another thing is try using Marcin's (redhardsupra) MAF spreadsheet to curve the graph, works pretty good. What are you using to re-curve the MAF Table (ie: Wideband, Dynamic Airflow, LTFTs)?
If you are in SD mode and tuning the MAF, the ECM will ignore the input from the MAF, you will be pretty much doing nothing. You need to re-enable the MAF and use the AFR Error % logged against the MAF Table, while logging MAF Hz. Or you could plot the Dyn Air against the MAF Table to shape your MAF Curve before you enable the MAF. Another thing is try using Marcin's (redhardsupra) MAF spreadsheet to curve the graph, works pretty good. What are you using to re-curve the MAF Table (ie: Wideband, Dynamic Airflow, LTFTs)?MAF Hz vs. Dyn Air is a starting point. After you get that, you should re-enable the MAF and log Hz vs %AFR_Error to dial it in.
05-11-2007, 01:38 PM
#6
Originally Posted by SSpdDmon
I think he was saying he's logging MAF Hz vs. DYNAIR in SD (not MAF Hz vs. %AFR_Error with the MAF active) and that's creating a not so smooth MAF curve.
MAF Hz vs. Dyn Air is a starting point. After you get that, you should re-enable the MAF and log Hz vs %AFR_Error to dial it in.
MAF Hz vs. Dyn Air is a starting point. After you get that, you should re-enable the MAF and log Hz vs %AFR_Error to dial it in.
I tend to go over the entire curve and analyze the new points, then hand smooth the old points based on the trend of the new points. Resulting in a smooth curve.
05-11-2007, 02:07 PM
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Originally Posted by 12secSS
I see, said the blind man.
I tend to go over the entire curve and analyze the new points, then hand smooth the old points based on the trend of the new points. Resulting in a smooth curve.
I tend to go over the entire curve and analyze the new points, then hand smooth the old points based on the trend of the new points. Resulting in a smooth curve.
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05-11-2007, 02:08 PM
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Originally Posted by SSpdDmon
I think he was saying he's logging MAF Hz vs. DYNAIR in SD (not MAF Hz vs. %AFR_Error with the MAF active) and that's creating a not so smooth MAF curve.
MAF Hz vs. Dyn Air is a starting point. After you get that, you should re-enable the MAF and log Hz vs %AFR_Error to dial it in.
MAF Hz vs. Dyn Air is a starting point. After you get that, you should re-enable the MAF and log Hz vs %AFR_Error to dial it in.
05-11-2007, 02:22 PM
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I don't know much about HPT....but, I sort of do what George is talking about by using the compare feature in EFI Live. Basically, I load a stock file in the background and it'll show me the % difference between the current and the compared file. So, I can see the trend moving along the curve as far as differences from stock. Then, I make general adjustements to the range I'm working on. You could also create a simple sheet that does this in Excel. Paste in a stock MAF table and your current MAF table. Then, create an equation row that calculates ((current/stock)-1) for each Hz. Format those cells as a % and you have the same thing. That will help you see the patterns for the various MAF Hz ranges. Then, you can adjust/hand smooth as needed.
05-11-2007, 05:23 PM
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Originally Posted by RedHardSupra
it's easier than that. just use maffreq vs dynair scatter chart in excel, and use a 3rd order poly fitting. use the equation for that fit line to create the calibration values. that's it.
haha! You guys are so much more way advanced than I will ever be, esp in mathmatics
Do you have any scatter charts I could just plug in the info?
05-12-2007, 01:44 PM
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Originally Posted by SSpdDmon
I think he was saying he's logging MAF Hz vs. DYNAIR in SD (not MAF Hz vs. %AFR_Error with the MAF active) and that's creating a not so smooth MAF curve.
MAF Hz vs. Dyn Air is a starting point. After you get that, you should re-enable the MAF and log Hz vs %AFR_Error to dial it in.
MAF Hz vs. Dyn Air is a starting point. After you get that, you should re-enable the MAF and log Hz vs %AFR_Error to dial it in.
I tried to figure out how to log dyn air vs maf but cannot figure out what needs to go where in order to get the proper information that I can just plug into the editor under maf frequency. Can anyone explain this part to me??
