kvu

If the pe f/a vs rpm table takes over (by tps %)then why does it matter what the gr/sec is @ ?

Grumpy

It's just that there is alot more to then that.
If the ecm only cared about gm/sec, then why does it do the LV8 calculations?. In some ecms the ecm does a VE table based on LV8, and some VE to grms/sec.
Then you have all the LV8 enables. An default values based on Gm/sec.

I've got a bunch of time in on the 31T code, and just scratching the surface on how things lace together.

And to directly answer you guestion,
the ecm needs to know the air mass the engine is using to calculate the AFR. There are ways to get around doing it correctly, but the engine will be happiest when done correctly.

kvu

You stated the engine need the air mass to calculate a/f ratio.I thought the ecm needs air mass to calculate load for fuel and spark distribution.I thought that is what the bua hak shows.But thats from a guy that does'nt know assemby language(me).I want to get this right,so where am I wrong.The thing is the s/a, now IF the maf maxes at 3600rpm you will run out of load calculation.Would'nt that fix the total advance from 3500 up?That is not a bad thing,just like a vac dist.But I see your point as the engine will run out of lv8 calculation at 255.What would you think the limits of the maf system in terms of hp,stock and non stock?

Grumpy

MAF or MAP all they do are calculate the airflow thru and engine. You can call it VE, or LV8 they both show engine load.

MAP systems use more filtering so they need to be closer calibration wise.

The new ZO6s use MAF and make 400HP out of the box. The reworked set up in my car reads to about 500 gms/sec.. But, the resolution gets bad. At teh higher grm/sec the MAF developes spikes, and the injectors get erratic. So I'm going to use the MAF for around town, and N/A, as the turbo begins to spool I'll switch to MAP.

Making HP N/A, using a MAF takes being really clever. The model is the ZO6s. While they did away with the screens they made sure the air passing over the sensor was relitively straight.

kvu

Gee,I don't think my 400 will be banging 500 g/sec.But I get what your saying.I have a g-tech and a wide band and I have got my 400 tpi in the high 12 second range.Not sure how much hp that is.My car weighs 3400lbs though which is not bad for a street car. Grand Nationals are animals.I have restored a few,one of em my boss charged 7 grand of paint & body work.The owner died and his punk kid tore it up.Then his mom took the car back and sent it to the resto shop I was working at.My boss told me she was a ten second beast!

CORKVETTE1

i dont know all this talk about maxxing out the maf sensor ina 13 or 12 sec car is absurd mine is a 11:49 car with more left there is anther guy over on the vette forum who gos 11:5 et and is a maf car these guys on these boards will tell you to convert to speed density but there cars run 14 sec maybe 13 sec maybe if they put in as much effort in trying to make there cars run ala more power and quit converting to speed density maybe they would be fast also