The standard ZO6 MAF is not calibrated for use with the LT1 PCM. This causes lean fuel corrections in closed loop which then alter WOT fueling in an unpredictable manner.

 

I was under the impression (perhaps falsely) that the ZO6 MAF sold by LS1speed.com was calibrated for the LT1 PCM.

 

My bad I just went to their site and it does state it's calibrated so it's essentially the same thing as the Granatelli

When I saw ZO6 MAF I just thought of a stock ZO6 MAF.

 

FWIW, having dynoed vehicles w/ Granatellis as well as after market replacement ends, after the computer gets used to the new ends OR the granatelli there is usually a 3-4rwhp (6-8 rwhp on a LS1 f-bod) gain on a vehicle that has a CAI and catback....that is assuming the rest of the vehicle is in good running order. Those numbers are from a 3 back to back pre-modification runs followed by a total cool-down, the new MAF, and 3 back to back post-mod runs....naturally with SAE standardization of all the weather elements that would effect it. Otherwise a change this small would be "fluff" that would be difficult to decipher....even worse so if you're using the SOTP meter

 

This is true if you do NOT input the correct MAF Flow Vs Freq table.. (E-mail me if anyone wants it)

I've been running a GM Factory Z06 MAF for almost 2 years now with awesome results.

There is one warning I will give though.. due to its increased diameter (85mm) the inlet is 1/2" larger diamter, 4" vs Stock 3.5". In my application this was not a problem due to the 4" outlet of the WS6 airbox and the perfect fit of a stretched 1/2 Fernco Coupler.

Not to mention if it ever fails again $85 at any GM dealer and I'm back in business...

But... unless your MAF fails or you're at some HP levels where your TB/MAF are causing losses due to piping restrictions then I'd upgrade, otherwise the stock MAF is very good.

 

You guys have really confused the crap out me now. My stock maf is dead. what should i do. I am not buying a used maf. I can get a stocker for 250 or i can go with a granatelli. My car is basically all bolt-ons with hypertech tuning. I can prolly pickut the granatelli for cheaper. Please someone give me some guidance since the whole thread went back and forth. thanks, Michael

 

Honestly I would either replace it with:

Stocker; best bet, most reliable
GM Z06/LS6 MAF; Good price, Requires a little extra to "fit", Requires either a Mail-Order Tune, or an LT1 edit tune, the Hypertech will not work, Also requires adapter cable
Then it's a toss-up for both the Grantelli, and the LS1-speed Z06 MAF.

 

What's the diff?

 

Granatelli is crap. Replace it with the 85mm Z06 MAF...conversion kit awailable at ls1speed.com under Induction...almost half way down the page right below the crappy overpriced Granatelli...

 

I'm trying to figure out wha't the difference between the Z06 MAF and the Granatelli. To me it jsut seems the same.. Thier both Bigger MAF's and have custom tuning. According to most of the post I've read on hear either way the CPU will reclaim it's original MAF measurments when it recalibrates itself....so aren't both of these items pointless? WOuldn't the best option be to just get ported MAF ends since it eliminates and actual physical restriction? No matter what the MAF Sensor is telling the PCM there still will be more air comming in due to the removed material...so aren't the Z06 and Crapetelli both Crocks in that case?

I'm so confused after reading all these post.....

I'm worse now than when I started.... One side says they suck Blah blah! Then another side says thier awsome...but what is the real story...what are the true facts???

 

I think a lot of people are making a lot of confusing statements. One of the old things I used to hear when I got into tuning over a year ago was when you port a MAF, you need to increase the MAF tables (between 8% and 20% was what many people said) in the PCM in order for it to read the flow correctly. However, after spending the past 6 months tuning my own cars, as well as other people's cars, I've found that this is totally untrue. The porting of the MAF doesn't change the sensor reading. The filaments will send the hertz rating back to the PCM, the PCM will read that hertz rating and convert it to the gm/sec airflow reading in the MAF calibration tables, and use that gm/sec airflow reading as how much air is going into the engine. If you play with the tables, it reads incorrectly and the PCM will then adjust the fuel accordingly in Closed Loop to make sure the O2 sensors reading will be 450mV, or 14.7 A/F ratio.

Porting the MAF will only decrease the amount of vaccuum required to pull air into the engine (as someone has already stated). This in no way changes the MAF sensor's readings for how much air is flowing through it. It will still flow the same air, it just won't put quite as much requirement on the engine to produce as much vaccuum to pull the air as before (I'm not going to debate on how much of a power increase porting the MAF will give, in my opinion it's probably only 1-2 HP on a stock car). The only time you would need to adjust the MAF tables would be if you converted to a Z06 MAF, which has different characteristics for the hertz ratings. It's the same principle behind the CAI and other intake restriction-lessening modifications. They don't flow more air, they just make the engine work less to flow the air to the engine. If they actually made more airflow, it still wouldn't really matter, because the greater airflow would still be read by the MAF's filament and there would still be no need to adjust the MAF calibration tables.

The Granatelli MAF is suppose to require no alteration to the MAF tables, because it supplies it's own correction to the hertz ratings. That's why tuners like myself don't like them, we don't know what the actual gm/sec airflow rating is. If we do need to make any adjustments to the MAF tables to correct a problem (such as high/low BLMs), you are just guessing with a Granatelli MAF. As for the claim of 15 RWHP, again, I doubt it. Probably more like 1-2 HP like a home-ported MAF.

And finally, for those people who say that porting the MAF will cause problems, the ONLY reason why it would is if you damage the filament that reads the gm/sec airflow and sends the hertz reading to the PCM. I ported/polished my MAF myself almost 3 years ago, and never had any problems. Never felt any increase in power, either, but hey, it only took me like 2 hours of time to do. Then I got into tuning and spent some time examining what happens when you play with the MAF tables. It didn't matter if I increased the tables by 20%, 15%, 10%, or 5%, the car still ran fine. The BLMs were lower the higher you increased the %, but it still ran fine. Same thing with decreasing the tables by those same values. This caused the BLMs to go in the opposite direction and be much high. But again, the car still ran fine. But again, this is my opinion on the matter. You are welcome to take it as you will and add your own opinion as you wish.

 

my camaro showed almost an 8hp increase with the z06 maf compared to stock.

 

I think the large thing that is confusing to MOST people is that there are 2 DIFFERENT "Z06 85mm MAFs"

There is the LS1-speed/Grantenelli version of this MAF; which has the "hacked" module that is supossed to allow you to run it without any changes to the PCM.

There is also the True General Motors 2002 85mm found STOCK on the Z05 Vette. This is the unit that I am running and have ran for almost 2 years now with ZERO issues. I have the table from a '02 Vette that has been adpoted for use in the LT1 PCM.

There IS a difference between them, one is "hacked" the other is a stock piece that works flawlessly.