NefMoto

Technical => Tuning => Topic started by: Fuscus on September 29, 2024, 12:00:44 PM



Title: ME 7.5 100mm MAF linearization
Post by: Fuscus on September 29, 2024, 12:00:44 PM
Where can I get a 512x1 linearization map for a 100mm MAF? I could only find the RS4 which is 90mm.


Title: Re: ME 7.5 100mm MAF linearization
Post by: prometey1982 on September 30, 2024, 12:08:10 AM
Умножь линеаризацию для 90 мм корпуса на отношение площадей между 100 и 90 мм. Короче, если отбросить коэффициенты, то выходит, 100*100 = 10000/(90*90) = 10000/8100 = 1,23 раза.


Title: Re: ME 7.5 100mm MAF linearization
Post by: Fuscus on September 30, 2024, 12:45:38 AM
Thx, I was about to make a pattern in excel from 70mm 80mm and 90mm mafs but didn't know how to. Your solution sounds way simpler. I think I'll do the same on all 3 and make a mean value.


Title: Re: ME 7.5 100mm MAF linearization
Post by: Fuscus on October 01, 2024, 09:41:29 AM
Turns out the RS4 maf is only 83mm inside not 90mm. This is what I came up with but none work normal. The best results I had with the one transformed from the RS4 maf beginning with a lower value than the original. If you compare the different sizes original mafs you see that they each begin with a lower value as they get bigger. If I just multiply the map with the factor I get a bigger map overall which doesn't seem correct. I calculated the difference between each next value to the other and obtained my pattern, then multiplied the differences with the ratio factor. When the engine gets hot and the idle stabilizes it tends to die and in high revs it hesitates in revving and blows black smoke.


Title: Re: ME 7.5 100mm MAF linearization
Post by: prometey1982 on October 01, 2024, 10:08:49 AM
Это все из-за того, что ты не учел переменную MLOFS, равную 200 (2000, если смотреть значение без множителя). Перед тем, как делать преобразование, нужно прибавить MLOFS к значениям карты, потом сделать умножение на (100^2)/(83^2) и вычесть MLOFS.


Title: Re: ME 7.5 100mm MAF linearization
Post by: _nameless on October 01, 2024, 11:26:03 AM
Whats your target power? a 4 inch maf housing seems quite overkill 


Title: Re: ME 7.5 100mm MAF linearization
Post by: Fuscus on October 01, 2024, 12:51:02 PM
Holy fuck it fucking works. I had to rise the idle to 1200rpm. I'm thinking the sensor isn't sensitive enough or smth for 7-800 rpm in this big pipe plus constantly dipping below 600 and near stalling, the spark plugs were getting wet. The setup is basically a dragster setup, high profile cams, pistons, rods. The car went to a professional tuning shop without a maf and a stock ecu. They blamed the engine/wiring when they couldn't make it run properly and I was very pissed off bcs I was the one who did the wiring. I wanted to demonstrate the opposite with this. I installed back the BAM injectors from the previous engine and started with the stock S3 file. Wanted to make everything as stock as possible to eliminate these 2 engine/harness possibilites. I had the engine run well enough with a diesel maf in a 60mm housing and wanted to confirm it with this rescaling thing. Still have to make a run though. I just revved it on the spot and it was fuckin mint, no misfires no backfires, I'd show you a video.


Title: Re: ME 7.5 100mm MAF linearization
Post by: Fuscus on October 01, 2024, 12:54:18 PM
This is the map I used. Of course there are still ecu limits and whatnot to use this air properly.


Title: Re: ME 7.5 100mm MAF linearization
Post by: Fuscus on October 01, 2024, 01:15:48 PM
Here's a video of it
https://www.youtube.com/watch?v=pmjS8BwCmas