I purchased one through Thunder Racing a few months ago, but only got a chance to use it not long ago. So far I have to say I am not impressed at all! I brought it to the race track to try and help tune the car better and get a better e/t. When the GMS MAF was installed the car didn't idle right, it hesitated and bucked under low throttle, and did not improve my e/t at all. I then made an adjustment, which is difficult to do with the extremely small screw they have put there for adjustments, and ended up with similar results. I did this a couple of times with no change.

I then put the stock MAF back on the car, and on the next pass ran my best time which is in my sig. Plus all idle, and low throttle issues went away and the car ran fine. So I am not pleased but I am not giving up. Next year I will put the GMS MAF on the car in the spring and let the computer get used to it. Plus, perhaps you need to make larger turns with the screw to get the results you are looking for. I was only making small adjustments. So I will try again next spring. But as of right now, I am not impressed but haven't given up.

 

You should be using a scanner so that you can have some idea whether you should dial in more air or less air. The idea of the adjustable MAF sensor is to dial in BLM values that are 128 or less. Then, along with an AFPR, you set the fuel pressure at a value that gets you 12.8 AFR at WOT.

As you change the fuel pressure the BLMs will also change, so you will need to iterate between the two adjustments, MAF & fuel pressure.

 

I had that thing on my car for about 10 minutes. Determined it to be a complete waste of money and the car ran worse with it. I returned mine.

 

I think that that is why a scanner is so important in tuning the engine. You got to know where the engine functions were at before and after a major change like a MAF change.

 

Is there anyone who has tried this unit, and actually likes it?

 

sorry I am off subject

Granatelli sounds like Ghirardelli who makes really good chocolate
mmmmmmmmmmm chocolate

 

any updates on this item?
anybody used it along with a scanner to see any benefits in what it does?
how could it be used in conjunction with tuning a chip if at all?

 

I will be giving some updates in a few months. My car is in storage for our Canadian winters here, but when the track re-opens I will let ya know. I have purchased the hardware to burn my own chips this summer so I will see what happens with that and the GMS MAF.

 

I just installed one on my car and it idles better than ever. Ive noticed alot more power and throtle response. I havent even adjusted it yet and I have alot of mods done so Im sure Ill see even better results.

 

Does the Granatelli MAF have a larger internal diameter than the stock one? I'm looking for more air flow. Not tuning. Allen

 

Out of the box it flows more than a stock unit without the trouble of removing screens.
As far as adjusting, I've yet to dyno or datalog to see if I am running lean/rich to adjust it.
Has anyone messed around with it yet?
I'm not sure how big of turns on the screw to turn, etc and what to expect exactly.

 

I just got done tuning mine. Just a quarter turn of the screw makes a pretty big difference. I just used a dvm to my o2 sensor to adjust it. Its kinda hard doing that way because the voltage jumps around so much. After road testing I think Ive got it just right. I raced a lancer evo and dusted him. Nothing like smoking a **** burner.

 

What mods do you have Dave?
Which way were you turning the screw, as in what does the dvm->O2 tell you, to make adjustments?

 

I can't speak about Granatelli for GM cars....I hear their MAF's cause a lean condition though...


What I can say, is that, I ran one on my 5.0....calibrated for stock intake...and anything beyond stock, in the SMALLEST degree, would throw a check engine light. But it did run very well....just, only on a stock setup.

 

It is only a band aid to fix improper tuning.

It has a finite range of adjustability and with enough playing u can get it close, but still not optimum.(for fueling only)

Also it does nothing for your timing which should be added to tuning your combo to hopefully find your new best optimum, both at cruise and WOT.

For about half the cost of the "wonder maf" you can be tuning your own setup, both the fuel and the timing and have freedom to change many more variables at the same time.

Not arguing, just giving my honest two cents.

later
Jeremy

 

I have cam,rockers,headers,no cat,flowmaster,hypercrap chip,siamesed runners,ported plenum,ported heads, adjustable afpr,transgo shift kit, k&n's, ram air, all accel ignition. When I installed the afpr the adjusting srew was sitting right against the plenum the lowest I could set was 55 so it was running a little rich and would bog of the line. It wouldnt spin the tires till about 1500 rpm. I was able to adjust it just right an able to smoke them again. With dvm you can read the voltage from the o2. There is an article about in the tech section on the homepage. You could easily adjust by idle and test driving. I mounted mine sidways so I could get to the screw easy. Clockwise rich counter lean. It has a huge adjustment range. I am very happy with it. Car runs better than ever. It has a different sensor its not the thin wire type. Its supposed to read changes in airflow faster and be more reliable.