----------UPDATE-----------
well, these are the results of a crap MAF, i swaped the electronic sections of the maf between the aluminum bodies of the modified and stock sensors and the performance followed the electronics, not the modified body.

there may still be some performance difference from the modified body, but it would be far less than the difference of the electronic section of the sensor. whenever i goto cordova next i'll find out by swaping the aluminum body but using the same electronics. there does seem to be a slight edge to the modified body, but its not impossible that the car could put down the same or better numbers with the stock body at the track.

the guy i work with is still planning to get a new maf regardless... because aparently his is junk too. trying to clean my old MAF didnt seem to help it at all. so for anyone that thinks thier 3400 isnt running right, try swapping a maf. the sensor seems to cross refrence to a huge number of vehicles, so it probly wouldnt be hard to find one to borrow, or get a cheap used one.



---original msg---

run#1 run#2 run#3 run#4 run#5 run#6
60' 2.439 2.443 2.497 2.946 2.993 2.498
330 6.952 6.944 7.094 8.361 8.524 7.106
1/8 10.725 10.714 10.924 12.648 12.879 10.946
mph 64.53 64.96 63.89 56.99 56.17 63.39
1000 14.004 13.970 14.237 16.410 16.674 14.275
1/4 16.750 16.692 17.007 19.575 19.853 17.053
mph 82.20 82.97 81.61 71.47 71.18 81.30

runs 1, 2, 3, 6 made with modified mass air flow sensor
runs 4, 5 made with stock mass air flow sensor

i cant belive it, the only thing changed was the MAF and it was worth over 2.5 seconds and 10mph!

runs 1, 2, 4, 5 were clean runs, on runs 3 and 6 there was just a little shutter or light tire hop shortly after launch.

the car is a 2000 LS 3400 w/132k mi, engine/performance wise it is competely stock aside from a drop in k&n air filter.

when i showed up at cordova i already had the modified maf installed, and i had planned to make 3 runs with it, then 3 with the stocker. but when i launched on run #4 i thought i broke something, trans slipping? tires spinning? maybe the torque converter is messed up... but then by the time i was a few hundred feet out i realized, this is how it always ran for me, i'd b

 

well, i punched my numbers into a horsepower calculator, and assuming a 3600lb vehicle weight (including driver) it says that in run#2 i was making 189hp at the flywheel based on mph and 181hp at the flywheel based on et. and in run#4 i was making 121hp at the flywheel based on mph and 112hp at the flywheel based on et. maybe the stock maf was f'ed up.

anyone else have 1/4mi times for a stock 3400, or from test articles?

 

What MAF did you get? Impressive #'s.

http://www.cardomain.com/ride/2319272

 

its just a stock one modified, removed the screen and completely removed the center divider.

 

Wow!!!! That is an insane amount of power for that simple mod!!

 

and its free.. wow. makes sense if you read this article in chevy high performance

Bolt On Parts - Dyno Proven Bolt-ons - Tech




[/align]
Mass Airflow Sensor
The bolt-on
Granatelli Motorsports' Mass Airflow Sensor with cold-air tuning. $300

The mule
'02 Camaro SS fitted with a Volant cold-air kit and SLP Loud Mouth exhaust. Power measured at the rear wheels.

Our take
The increased airflow and performance calibration provided by Granatelli's MAFs improve power and throttle response.

Before
Max torque: 285 lb-ft @ 4,700 rpmMax power: 276 hp @ 5,400 rpmAverage torque: 243 lb-ftAverage power: 198 hp

After
Max torque: 302 @ 4,500 rpmMax power: 288 @ 5,450 rpmAverage torque: 277 lb-ftAverage power: 208 hp

Difference
+17 lb-ft+12 hp[/align]

 

Well, it would.. When you look at the aftermarket MAF's thats basically all they are is a de-screened, de-walled version of the stock sensor. The screen and divider cant be good for reducing turbulance in the air flow. Turbulance slows the air flow, and if you can smooth that out, you will see gains.

Now those gains are extremely impressive... Id probably guess the original MAF was on its way out, or is a very poor design. Ive been looking at the LZ4's MAF, and can see where GM cheaped out.. Huge honeycomb screen, and a huge divder.. Poor design.. Maybe I'll look for another maf at a scrapyard to play with..

 

I can't figure it out, but it doesn;t make sencs. Our cars should not run the quarter mile stock in 19.5 sec. That shows that the driver was not good (no offence). our cars stock should be running mid to high 16 sec. stock. Until I see actual dyno results, I don't think this mod give you much if any gain at all.

EDIT: sorry, I re-read it again. I think your stock MAF was bad, which is why your times were horrible. But like I said, our cars run mid to high 16's stock, so I don;t think this will give a car any gains if their stock MAF was working properly.

 

well, results have been duplicated on another car, 03 monte with 40-50k mi. didnt take it to the track but the performance difference felt similar. car belongs to a guy i work with and he's planning on buying another used MAF sensor for me to mod for him.

i have to agree with donutboy, that this shouldnt make this kind of difference.

but punching the numbers into a horsepower calculator reveals that. these cars are rated for 180hp, and i'm looking at about 185hp with the modded maf. with the stock one aparently it wasnt running right. but then neither was this 03monte that i put the sensor on today.

sometime in the near future i'm planing to disassemble my 2 MAF sensors and swap the electronic center section to see if the performance follows the moddifed body, or the electonic section of the MAF.

also in the future, 2 of the guys at work have wives driving grand ams w/ 3400s and we'll see what happens when the moddified sensor is put on one of the grand ams.

 

btw, anyone else have have any track times fora stock 3400 monte, or seen any test articles?

if anyone with a 3400 could.... go out and measure a 1/4mi, see if your car finishes a 1/4mi at aproximately 70mph or at about 80mph.