MAF vs SD
08-07-2007, 06:53 PM
#42
Originally Posted by Frost
Enough condescention already, especially since all you have done here is build a straw man. The OP doesn't have a Ling MAF, 85mm MAF, an intermedite MAF handler, or anything other than a stock PCM. I'm not talking about race cars, aftermarket MAFss or EMS's. It's true that the stock PCM can read up to 512g/s but the stock MAFs curve ends before that, and so does it's accuracy at the upper threshold. That's why the table plateaus. Can we at least talk about the same things here?
Could you explain the "handlers"? The 85mm meter has been on all '99 & up 4.8L, 5.3L & 6.0L pick ups, using the same box, and often operating system, as the LS1 cars.
The 85mm table does not plateau. The 85mm GTO table goes to 512 gm/sec.
I've tuned three or four of those with a Maggie lately and didn't max the table.
Last edited by Ed Wright; 08-07-2007 at 07:03 PM.
08-08-2007, 08:03 AM
#43
TECH Fanatic
MAF is so superior that over 2 million efi hemi engines run one. Oh hang on, they dont! They are all SD... Hmmm...
I wonder why GM also uses SD to QA/blend MAF readings up to 4000rpm?
Yeah SD sucks, lets use MAF because its so easy and so cool and who can be bothered doing a good tune anyway? Let the MAF fix my f*ckups, kewl!
I wonder why GM also uses SD to QA/blend MAF readings up to 4000rpm?
Yeah SD sucks, lets use MAF because its so easy and so cool and who can be bothered doing a good tune anyway? Let the MAF fix my f*ckups, kewl!
08-08-2007, 09:46 AM
#44
Maybe the GM factory race team knows something you and I don't? I'd guess they aren't too concerned what Chrysler does with the Hemi either. I know I'm not. They aren't really all that fast anyway. My point it 99% of the guy's cars on here won't run one bit faster, or drive one bit better than in speed density mode than they would with a correctly tuned MAF system. If you enjoy tuning your car that way, go for it. Saying people that don't agree are inept or covering mistakes is simply bogus.
I gotta tell you, a couple of factory calibrators get a real kick out of reading some of the stuff in this section.
And, I have to admit, your one funny guy.
I gotta tell you, a couple of factory calibrators get a real kick out of reading some of the stuff in this section.
And, I have to admit, your one funny guy.
08-10-2007, 08:41 PM
#45
I like this section from the car craft article.
MAF systems are much more flexible in their ability to compensate for engine changes since they actually measure airflow instead of computing it based on preprogrammed assumptions. They are self-compensating for most reasonable upgrades, as well as extremely accurate under low-speed, part-throttle operation.
I might go back to MAF myself till I get enough mods where it start to be a restriction. Why not utilize as many sensors as you can. With the MAF being able to adjust with changes in the air I would think the gas mileage would be better also. My gas mileage currently sucks with SD but I still have to get some more logs b4 I get my bins dialed in. Im a noob to tuning also but from what ive read unless your maxin out the maf why not use it?
MAF systems are much more flexible in their ability to compensate for engine changes since they actually measure airflow instead of computing it based on preprogrammed assumptions. They are self-compensating for most reasonable upgrades, as well as extremely accurate under low-speed, part-throttle operation.
I might go back to MAF myself till I get enough mods where it start to be a restriction. Why not utilize as many sensors as you can. With the MAF being able to adjust with changes in the air I would think the gas mileage would be better also. My gas mileage currently sucks with SD but I still have to get some more logs b4 I get my bins dialed in. Im a noob to tuning also but from what ive read unless your maxin out the maf why not use it?
Last edited by SpdFrk1990; 08-10-2007 at 08:49 PM.
08-11-2007, 02:22 AM
#47
TECH Fanatic
Originally Posted by Ed Wright
And, I have to admit, your one funny guy.
I dont think anyone is saying a correctly sized maf is a restriction, what is being said is that the stock ls1 ecm has inherent limitations when it comes to mid to high power applications such as strokers and forced induction which means that more control and flexibility can be gained from an SD setup, especially when running a custom OS. To deny that is to deny the world is round.
