VT 355 supercharged AFM issue

[shane1]

Hi Guys,
We are at it again, Heres one for the programmers out there.
Im currently tuning a VT supercharged 383. I have tuned this previously with great results
now i have come across another AFM issue. When i first set this car up last year we couldnt get
it to work as the airflow frequency would always max out and the car would run lean etc.
I fixed this issue with a card maf in a 4 inch pipe and that got all the afm numbers down so i could
tune it. The car is now back has a fresh engine with a bigger 383 crank in it(the old one ran a main bearing due to poor oil flow now remedied with a hemi oil pump conversion and a 9 litre sump.
This is where the problem starts again as now it misses above 6000 rpm right at the point it goes past 256g/s or 10400HZ. If i loosen the supercharger belt so it doesnt see the airflow it will rev to the limiter clean.im almost at the point of fitting an electronic clamp to the afm signal so it doesnt see the numbers above 256 but thought i would see if anyone has any ideas. The actual afm will keep reading way past 10400 but its obviuosly the 256 g/s that the ecu doesnt like . im using the enhanced bin file and adx which lets the ecu read past that but there is something in the code that kills it at that point.

VT_V8_$A6C_Enhanced_v0.80blu3836000.bin

VT_V8_$A6C_Enhanced_v0.80blu3836000.bin

[VL400]

Can you post the ADX you are using too, the VT enhanced V0.81 ADX wont playback either log for me

[delcowizzid]

i used VT_$A6_v1.01 it reads but probably not the correct values.for some reason its commanding 16:1 fuel ratio when the issue happens but without boost its actually reading higher numbers LOL maf tables all stock for some reason

[shane1]

yes that is correct as it has its issue it commands wierd afr etc .All strange readings always correspond with the 256g/s area,some runs have all good data just a miss at the same point.im using VT A6 v102 for adx

[delcowizzid]

use the enhanced adx thats designed for the enhanced code LOL

[shane1]

The enhanced adx doesn't always work , last time I checked the adx doesn't make the engine run !

[antus]

That sounds odd, the adx should not affect the engine. does it stop if its running then you try to connect with the enahnced adx? latest plugin? car type set to vt?

[shane1]

It's has nothing to do with the adx , I have been logging using a scan tool just did a few runs using a adx to post on here . The issue is in the way the code trips over itself at the maximum point . When I set this car up originally we tried all the mafs available along with the enhanced xdf etc nothing worked do I got around it by basically rescaling everything by placing a maf on a 4 inch pipe , unfortunatly now we are pumping a little more air this problem has come back , probably should have thrown the factory ecu in the bin six months ago but I like a challenge , last time The1 and I played around with all this a lot but always came back to the fact that the factory limit gets funky even though the afm is capable of reading higher

[The1]

rpm limit is set to 6000 in the tune so it'l be cuttin fuel after that.

[Jayme]

ah I htink I see a bit of miscommuncation here. ant thought your sentence meant the enhanced adx was preventing the engien from running.

the suggestion to use the enhanced adx was only mentioned because the enhanced code may have the data frame in a different order so some items ~may~ be showing incorrect. sounds like soem odd stuff happens up that high, ive never had an engine able to flow that much air on MAF code haha. I generally toss the maf pcm away and run it on an 808 with 12P and a 3 bar map sensor. never misses a beat and is just as tunable as aftermarket.

I hope you get it sorted though. sounds like some code debugging is possibly required... fun.