Want to know if this will help out my setup?

GRANATELLI GM TPI MASS AIR SENSOR CAMARO CORVETTE

http://cgi.ebay.com/ebaymotors/ws/eB...tem=7922857138

Let me know feed back...thanks,
Aaron

 

Personally I think it's a waste of money and dont belive that the stock MAF sensor is as big of a restriction that people make it out to be. I've personally gone 10.6@126mph with a stock untouched MAF in place, screens and all - and I was at the limit of the injectors at that point(55# inj). Granted I'm running a slightly different MAF sensor they are probrobly similar in flow properties.

HTH,
Steve

 

What, are you becoming Grumpy? 3.8 turbo 6 stuff doesn’t compare to V8 maf stuff at all… the maf that the turbo 6’s used was much more like the more recent LT1 and LS1 mafs then the TPI maf, and the ecm’s have almost nothing in common.

 

Where is that post that ski_dow_it had where he as testing the stock maf? He didn't have any lose and was putting down something in the high 500 rwhp...

I tried to search and couldn't find it.

 

First, the time that he was running doesn’t translate to anywhere near ‘high 500 hp.’ Second, just because you can get it to work at xxx hp doesn’t mean that the maf is actually working there. In Ski’s case what he was doing is tuning for up to what the maf could handle and then just adding a lot of PE (dumping fuel), and running race gas and praying that something doesn’t blow up.

It works, but that doesn’t mean that it’s a good way of doing it or that the maf is still doing something at that point

 

I'm going to make two assumptions here. First is the MAF question is based on if it is a flow restriction or not at the 500+ hp level and second that you know the specs on what the two MAF's actually flow(LC2 vs L98).

Now the only thing I know is that the LC2 MAF will only read up to 255 grams/sec but will flow alot more, enough to make well over 600hp and then some.

Now aside from how the sensors work, and what the different ECM's can do with that information(neither of these have anything to do with the question as I read it or with my previous comment)how do the two compare in their abilities to flow air?

And no I'm not Grumpy(though not exactly sure what is ment by that), I was simply stating my opinion and what I have done with a stock early style GM MAF sensor(aka not an LT1 or LS1 style sensor). If I'm wrong then I apologise but please correct me rather than coming off to me like an ***.

Steve

 

Grumpy is a board member (Bruce P), and a big time contributor to a lot of the GM ECM stuff. He has a tendency of posting what has worked on his GN in response to V8 and related ecm stuff (749, 730, 165…) that doesn’t particularly translate (in some cases not at all).

In operation, the GN maf is much more like the later LT1/LS1 mafs then it is like the TPI maf. Comparing the 2 is roughly similar to comparing one of the GM maf setups to a ford maf setup, that is to say, nothing really interchanges and they’re different enough that once you get outside of the basic operating principals of an IC engine, you can’t really expect one to react to things the same as the other.

Which flows more? I don’t know, how much pressure are you using to force the air through it? Relocate the maf after a supercharger and it’s more up to the boost pressure then anything else. Before or NA a lot of that depends on the air filter assembly… Both meter up to 255 but who knows how accurate that actually is. It almost ends up an arbitrary number that the ECM translates to something that is useful for it, that doesn’t mean that when both ECM’s are reading 255 both engines are ingesting the same amount of air. It does appear that the GN maf can meter more air, but best I can tell you’re not asking that question.

Let me ask you a question… what is the point of running a maf setup if it isn’t to give the ECM an accurate readout of the current airflow? So what if one will flow 500hp worth of air and the other 600 if one will meter 275hp worth and the other 350?

As far as “coming off to me like an ***,” sorry, stating facts as best as I know them. I would suggest you reread what I wrote since at no point did I actually pick on you or anything else (I can’t remember the last time I bothered wasting my time picking on anyone). If you still have a problem with it I’d suggest you learn to ignore “internet personalities”

 

No problems here, just maybe you should think about how your comments will come off before typing, and I'm sorry for taking what you said the wrong way.

As for running a MAF past where it is working, I dont know much about how it's done but do know the buick guys have been doing it scince day one. The way I understand it the MAF is used during part throttle cruise and light acceleration then once it crosses 255 g/sec the computer resorts to a programmed table for fuel based off of RPM and throttle position(kinda like a speed density system I suppose). We generally tune the stock ECM cars for the right a/f ratio at WOT in 3rd gear, though that has resulted in a slightly fatter tune in 1st and 2nd it. More recently we've been able to fix that by adding a patch that adds fuel by either gear position or even better by MPH, it also allows us to run a WOT timing curve that starts higher at 0mph and comes down gradually as the MPH goes up, my current programming starts the timing at about 21* and backs it down to 18* or so by the top end depending on how I have it adjusted - low airflow timing and WOT fuel is also adjustable.

I suppose you are right that exceeding a MAF sensors ability to read air is probrobly not the best way to do it, but I think if you are stuck working with what you have(meaning the abilities of the ECM and it's sensors)you can get it to work well, and take advantages of the situation as the turbo buicks have done. To answer the initial question again, it may not be the best way or the way for everyone, but if your willing to try I dont see why it couldnt work.

83 Crossfire TA I hope no ill feelings, we've butted heads before and I'm sure will again - it's what makes this stuff fun After all I'd hate to be in a place where we all thought alike. Where all think alike, no one thinks very much

Steve

 

Never ran a MAF before, and probably never will, but ive read almost all of the TGO MAF VS SD posts and Ski's stuff and Grumpy's stuff, and I never really understood one thing..


What is keeping people from running a bigger maf that has a lower voltage (gps) at a higher airflow than it normally would see? for instance if you double the size of the maf, I know you would lose resolution, but wouldnt the voltage (Grams per second) move up half as fast as before? then on your computer program, you can cut all of the fueling tables in half up to 128GPS- or better yet double your injector size and leave those tables alone all together.... Then after 128 (real world 255gps) you can account for up to 500gps of airflow. your resolution is cut in half, but at least you can keep the MAF working all the way to 700-800 horsepower??

 

I’ve thought about cutting the electronics/sensor out of the stock maf and mounting them in a larger tube or even running 2 mafs and averaging the output (essentially returning ½ the airflow of one maf)…

It seems to me that it’s mostly the fear of rewriting/rescaling the MAF tables as they’re used in the assorted code used by the 165 fueled by lack of info and bad luck with “bigger” setups. I don’t know that I’ve seen a really clear explanation of the scalars and haven’t experimented enough with them to really tell what’s happening. I can tell you that once you mess with the MAF things get really confusing, really fast.

Like I suspected at one point, there really is a magic number right around 36pph injectors with the maf setup at least. Below there it’s a no brainer to burn a chip and get it running, above there nothing responds like you expect it to. I’ve been running 42pph injectors in mine (intended as an experiment that I haven’t had enough time to experiment with), but with the few dozen chips that I’ve burnt for it I haven’t gotten one with acceptable driveablility. It’s easy to get WOT and that range good, but I haven’t had any that have worked well at cold startup, they always seem to have a really low idle, barely keep running and almost die on initial tip in until it gets warm. I’ve had some that were really quite good after that though, but lately I’ve been trying to trace down an idle/midrange problem which feels like a lean surge even though I have all indications that it’s actually rich at the time (I am wondering if I may have a non chip related problem here).

That being said, I’ve had absolutely zero luck burning something that starts up and runs correctly with a well ported maf and 36pph or larger injectors installed. Almost everything I’ve tried will not even fire correctly and if it does it will not keep running after that.

 

That seems like a really good idea, have you tried that yet? technically, you could just double the size of the injector, and leave all the map tables alone... i would think. or you could half the fuel tables, I mean, If i was going to run twin mafs, technically if you take both signals and cut them in half you basically have 1 maf's worth of airflow and twice as much airflow as you would normally have, so your computer would normally dump half the required fuel into the motor, which is why you double injector size and it should even out, all the way to 800HP...