: aftermarket (granatelli/other) Mass Air Sensors?



fubar569
03-30-07, 10:05 PM
Ok, so i noticed that alot of people with (somewhat) modded cadillacs seem to have a granatelli or other performance MAF on the car.

there is no direct part for the northstar motor, however there has to be some part that works if other people have them...

First, for those that have them, did you notice a gain?

second, what part do you have?

third, i've heard that we have the same maf as the LS1 corvettes and a number of other vehicles. if this is true, then any one of those maf's should work...theoretically...

just looking for some input on this idea first...thanks guys!

01STS
03-30-07, 10:23 PM
Yep you are right the LS1 mass air is a direct replacment for the 01 up Northstar. I am using a Granatelli on my car and it picked up my et at the track. I went from a 15.7 ( I was on my 20's at the time ) to a 15.3 in the 1/4. Same day same temp just 35 mins later. Hoping when our track opens next week to see if I can get into the 14's with the stock 17 inch rims.

fubar569
03-30-07, 10:49 PM
Yep you are right the LS1 mass air is a direct replacment for the 01 up Northstar. I am using a Granatelli on my car and it picked up my et at the track. I went from a 15.7 ( I was on my 20's at the time ) to a 15.3 in the 1/4. Same day same temp just 35 mins later. Hoping when our track opens next week to see if I can get into the 14's with the stock 17 inch rims.

the 01+? what about the 97-99 cars or thereabouts? mine specifically is a 97 deville and im looking for a possible alternative

EDIT:

searching GM parts direct has me scratching my head...it shows the 97 deville to use a different sensor than the LS1 cars, but the same sensor as the 92-2002 eldorado...which has a second part number for the sensor that is on the LS1 cars...so it SHOULD work? i dunno...if the 97 deville and the 2002 eldorado use the same sensor and the eldorado can use the LS1 replacement sensor i should be able to too...i'd assume...

dkozloski
03-31-07, 01:42 AM
Keep in mind that Andy Granatelli got socked with the biggest consumer fraud fine in history by the FTC.

fubar569
03-31-07, 03:59 AM
Keep in mind that Andy Granatelli got socked with the biggest consumer fraud fine in history by the FTC.



that i'm aware of too...thus why i wanted to test the waters here before jumping off to buy one. i've heard of mixed successes with MAF swaps...some getting nice gains while others losing power...it seems like most of the dynos i've seen of modified northstars have an aftermarket MAF on them and seem to do well...but as you and i know that doesnt always tell the whole story either...just looking for a few positive (or negative) ideas to see wether or not it would be worth it to try...

Ekindler0584
03-31-07, 10:10 AM
01STS. . . Did you reuse the MAF screen? Or did you leave it out?

Ekindler0584
03-31-07, 10:15 AM
Also, are you using the Granatelli part #350112? Was the plug an exact fit?

fubar569
03-31-07, 11:07 AM
Also, are you using the Granatelli part #350112? Was the plug an exact fit?

i was wondedring the same things...his seems to be the only positive account so far and it seems to be a bit out of the norm...waiting for confirmation..

EDIT: FWIW i was just doing a search over on corvette forum in the C5 section (the maf's swap) and they are dead set against it...it makes me wonder...if the MAFs are the same or are compatible...why such different results? could be quite a few things...

Ekindler0584
03-31-07, 12:23 PM
And as a side note... I think we might have our Granatelli's confused here... I might be wrong, but do some research on it. Same name, different companies. No fraud from the one producing these MAF's.

01STS
03-31-07, 02:54 PM
Use the same year Vette mass air for your year Northstar. If you have the early years with separate IAT and Mass air plugs use the early Vette style. 01 and up cars, GM put the IAT inside the Mass air with 1 simple 5 wire connection.

DO NOT REMOVE THE STOCK MASS AIR SCREEN!!! If you think this is a cheap and easy way to give you horsepower is will cost you about 4 HP on the dyno. I have seen it may times and it always costs hp.

dkozloski
03-31-07, 04:01 PM
And as a side note... I think we might have our Granatelli's confused here... I might be wrong, but do some research on it. Same name, different companies. No fraud from the one producing these MAF's.
Same name, same roots, different divisions of the same consortium.

Ranger
03-31-07, 05:06 PM
01STS. . . Did you reuse the MAF screen? Or did you leave it out?
It is not a "screen". It is an air flow straightener.

codewize
03-31-07, 05:40 PM
If you go with Granatelli the part number you want is 350119-C for the 01+ N*.

Now lets take a look at some recent information we've leaned, again.

What does the MAF control, or help control that you think it's going to make an improvement? If you're thinking AFR (Air Fuel Ratio) you're wrong. Air Flow, maybe? Wrong again. No one but no one has dyno proof that aftermarket MAF's do anything at all. That 4/10th of a second on the track can be anything. That could be the lost weight from the fuel you burned the previous run. Show me proof from a dyno and I'll listen.

We do however have proof that adjusting the AFR from totally lean to totally rich with NO affect on the HP output at all. The computer is to smart to be fooled by that. Not to mention there are several sensors involved most of which will compensate for the changed MAF signals and bring the car back to where it wants it.

Don't waste your money.

01STS
03-31-07, 08:37 PM
Yeah I picked up that amount because I burn 400 lbs of fuel in one run................

fubar569
03-31-07, 09:26 PM
Yeah I picked up that amount because I burn 400 lbs of fuel in one run................

im not doubting your results, but they are so atypical of MAF swaps that it is hard to believe...you might have had a faulty MAF or an improperly calibrated one and the swap to a good one netted you those results...your story is one good one out of a mound of bad reviews we've all read...but if yours worked that well for you i am glad you got that kind of performance from it...i suppose if i got one used for a good deal it couldnt hurt but to try it for a couple passes...

codewize
03-31-07, 09:37 PM
I'm not trying to start a war I'm simply saying that 4/10th of a second is nothing. A 1/4 mile run could very that much easily, unless of course you're super robot racer and never ever alter from run to run.

I've got a guy right now who will sell me a brand new in the sealed box Granatelli MAF 350119-C for $150 and I'm still skeptical. I'm really not into throwing money away. I want to try it in the worst way but I don't want to waste $150. Especially now that I have, what could turn out to be a $2000 transmission repair.



Yeah I picked up that amount because I burn 400 lbs of fuel in one run................

fubar569
04-01-07, 11:44 AM
I'm not trying to start a war I'm simply saying that 4/10th of a second is nothing. A 1/4 mile run could very that much easily, unless of course you're super robot racer and never ever alter from run to run.

I've got a guy right now who will sell me a brand new in the sealed box Granatelli MAF 350119-C for $150 and I'm still skeptical. I'm really not into throwing money away. I want to try it in the worst way but I don't want to waste $150. Especially now that I have, what could turn out to be a $2000 transmission repair.

350119-C - 150? ......... where is he located? that aside...would he let you try it first? its like a 10min swap...or...could he work something out like if i wanted to give it a shot? a can find a dyno close and give some before and after if it'll work on my 97

fubar569
04-01-07, 02:23 PM
ive summed up all my research with the following statement

Shows 2000 eldorado has 2 different MAF part numbers. Part 1 is the same sensor as my 97 deville, the 2nd is the same as the 97+ corvette and CTS-V and most other LS vehicles…theoretically the sensor should work for me…


note it shows this for every year of eldorado 97-2002...

if i could get my hands on one i'd at least be willing to try before and after dyno runs...

but i dont think i'd go out and buy one...i could use that 300+ dollars for some other things like LSD / converter

codewize
04-01-07, 06:25 PM
I'm not sure where he's located and he wasn't willing to let me test it out. He doesn't want it opened until it's sold. I, for the life of me can NOT find anyone with a dyno around here. I'm working my ass off to locate one for just these purposes but so far it's no good.

He wanted $300 for it and I kept whining. He apparently bought it for a gift that was never given.


350119-C - 150? ......... where is he located? that aside...would he let you try it first? its like a 10min swap...or...could he work something out like if i wanted to give it a shot? a can find a dyno close and give some before and after if it'll work on my 97

jadcock
04-02-07, 11:31 AM
It sounds like 01STS ran one run (15.7) with his 20" wheels and the second run (15.3) with his 17" wheels? That would easily account for the difference right there (the 20s being heavier and slower). If those wheels weren't changed, there could still be a large number of variables that count account for the difference.

I agree with codewise -- a dyno is really the only proof...or if no dyno, more than 1 data point per modification at a track is needed for consistency. But that said, any data is better than nothing. At least you know the new MAF didn't slow you down any. But still, 15.3 is much more representative of what an '01 STS should do than 15.7. Methinks something might have been amiss with the first run (a headwind, bad R/T, bad launch, something).

01STS
04-02-07, 08:43 PM
Nope. I ran the same 20 inch rims, on the same day 35 to 40 mins back to back. I left the stick in drive and let the car shift its self and had the same 2.2 60 foot on both launches. 3rd pass was the same 15.3 @ 95 and another 2.2 60' .
This season I want to run my stock 17's to see a slip in the 14's. The car has run 15.0 with the stock 17's with nothing other than the Corsa exhaust.

jadcock
04-03-07, 09:29 AM
So it did 15.7 with the stock MAF, Corsa exhaust, and 20" wheels? That seems slow. 15.3 sounds much closer to what it should do, especially with an exhaust already on there.

01STS
04-03-07, 09:37 PM
Plus there is close to 100 lbs of stereo shit in the trunk as well.
The 20's are very heavy.
We'll see what happens on friday night when the track opens again.

danbuc
04-03-07, 10:48 PM
What elevation is the track at...just out of curiosity?

01STS
04-04-07, 09:22 AM
sea level

danbuc
04-05-07, 06:34 PM
I take it they either don't prep your track very well, or are not accustom to drag racing in general regarding your 15.0 second time. What was your 60ft time, and trap speed on that run if you don't mind me asking. I'm just curious, since the car SHOULD be at least 2/10's faster than that.

01STS
04-05-07, 08:37 PM
It is a street legal night and I know they do not prep very well. My 60's are posted above.

fubar569
04-05-07, 09:09 PM
hows this for goofy...some older info on caddyinfo has people unplugging the MAF entirely for a performance boost...people running mid 14's...all the way into the 13's with it unplugged with other (more serious) mods...that seems ludicrous to me...

alot of the runs are in under 50 degree temperature using a Gtech pro (accurate 1/4mi wise - trap speed is horribly wrong in personal experience).....

most interesting was this one:


99 SLS

Driver: Robert Lange

Total Weight with Driver: 4180 LBS Front: 2560 LBS Rear: 1620 LBS

Fuel: 92 Octane

Modifications

Removed plastic shielding under airbox and air intake under airbox completely. Removed airbox completely and replaced with 7" long K&N Cone Replaced MAF with Granatelli MAF that has a removed screen and is ported. 3" diameter echaust pipe from the resonator on back, to a 2.5" Y pipe, to dual 2.5" Dynomax Super Turbo Flow Mufflers with Stock tips replaced. Mobil 1 Synthetic 5W-30 Sunday 4/14/02 3:30 AM

Weather Conditions
Temperature 41 Degrees Humidity 100% Barometric Pressure 30.11 Wind S 6 MPH Dew Point 45
G-Tech Pro Data
1/4 Mile Runs
Run # 0-60 1/4 Mile Speed MPH
1. 6.01 14.39 102.9
2. 6.08 14.46 101.8
3. 6.10 14.53 100.5
4. 5.98 14.36 102.7
5. 6.11 14.49 102.1



=========



seems a little out of touch with the normal, but the 41 degree temperature sure helped out a ton! - also, werent the SLS the 275hp N*?

and theres a couple postings from mark99sts before he got crazy with the turbo. 13.9's from a corsa exhaust and a k&n cone according to what is there...

jadcock
04-06-07, 07:11 AM
Lower 14s with trap speeds in the very low 100s seem consistent with each other. I think that probably demonstrates how some of these mods work better on the track than they do in the real world. Track = sustained high-rpm driving, where a 3" exhaust would really flow nice for good top end. On the street, there's probably less of a gain since a lot of driving is much lower in the engine speed range.

Yes, SLSes had the LD8 powertrain (275 hp with 3.11 final drive). 2nd gear on those cars is good to almost 100 mph. :) A stock SLS could probably finish the 1/4 mile in 2nd gear (vehicle speed too slow to break into 3rd before the trap).

01STS
04-06-07, 11:16 AM
Well the weather is good today and the track is open. I will post results tomorrow with the stock 17's on the car and hopefully will have something in the high 14's.

codewize
04-08-07, 10:35 PM
I don't believe anything a Gtech Pro tells me. I think many other people will agree. I had one very securely mounted in my car and made a pass with it. It told me I made 245 HP and ran the 1/4 mile in 14.7 seconds.

Highly unlikely in a bone stock DTS. They're ok but I don't think my car will run that before any mods.

jadcock
04-09-07, 08:49 AM
I don't know about the HP claim (seems elevated), but the 14.7 seconds is plausible. A '01 DTS tested by a magazine did it in 15.0 seconds. An '01 STS did it in 14.8 seconds. Although most DTSes did it in the low-15 second range, 14.7 seconds isn't too far out of whack. If I recall, Car & Driver tested an '04 or '05 DTS and it ran in the high 14s somewhere. I'll have to look again. But taken with the seemingly high HP claim, it could be a bit elevated.

You usually don't see a Gtech OVERESTIMATE performance. I've often seen them UNDERESTIMATE it. When you're trying to set up a timed run, any slight movement of the car before you actually get going starts the timer. The timer often starts before you really start the run, so you end up getting slow times.

But of course, the Gtech is only a fancy estimator, so it shouldn't be relied upon as a sole data point. A Gtech told me my '97 SLS did 0-60 in 6.7 seconds. A look at prior magazine tests validates that. A race with a late '90s Grand Prix GTP (which is also supposed to do it in 6.7 seconds) validates that. So I believe what it told me that day, but only because it seems to be consistent with other data sources.

jadcock
04-09-07, 08:52 AM
Well the weather is good today and the track is open. I will post results tomorrow with the stock 17's on the car and hopefully will have something in the high 14's.

Did you get to run it down the track? With the stock 17s, you should be in the high 14s somewhere.

01STS
04-09-07, 09:39 AM
I did but I only got 1 hit and the track prep was poo. 2.45 60' and I stupidly left the traction control on and it cut fuel out spinning the tires at 3000 rpm. Hopefull next friday I'll try again.

fubar569
04-09-07, 11:00 AM
please do...we are eager to see how close you are to that goal! :thumbsup:

msta293412
08-02-07, 08:13 AM
I though I would chime in, for anybody who wants to know...I have the MAF for my 2001 sts, (JETTECH), basically exactly the same as Granettelli...And when I installed it, I did notice some seat of the pants gains.

codewize
08-02-07, 08:47 AM
Can you dyno the car. I'm interested in this because there are so many nay sayers out there. I would like to believe but I haven't seen any proof yet and when it comes to the car I want proof.


I though I would chime in, for anybody who wants to know...I have the MAF for my 2001 sts, (JETTECH), basically exactly the same as Granettelli...And when I installed it, I did notice some seat of the pants gains.

msta293412
08-05-07, 08:53 AM
I can...but, Im waiting on a pcm tune from AJ...Ill do it all then, with and without the pcm and MAF.

Submariner409
08-07-07, 02:40 PM
FYI, www.autoanything.com (http://www.autoanything.com) is selling JET MAF's for $275, free shipping. Use coupon code TWENTY.

fubar569
08-07-07, 04:25 PM
FYI, www.autoanything.com (http://www.autoanything.com) is selling JET MAF's for $275, free shipping. Use coupon code TWENTY.

BAH!!!! i almost have enough!

maybe next check i can send in my throttle body to RVM for boring and see what additional gains i can get from that...should be ~7hp and ~10ft/lbs

either that or i am gonna build a wicked SCSI based desktop computer...i scored a 4ch U160 card for 44 bucks...160MB/s times 4 channels supporting RAID 5...i bet i max out my computer's PCI bus with the cheetah drives i wanna run :thumbsup:

msta293412
08-07-07, 06:02 PM
Jet MAFS for $275 is a steel.......I baught mine when they were first available last year....paid $385......They definetly give you a little more airflow, not to mention they read signals quicker than the stock MAF....

codewize
08-08-07, 11:39 AM
Screw SCSI. Save the cash and go for cooler, faster, more readily available SATA 300. And why would you put a performance degrading RAID 5 in a desktop?

RAID 5 has fast reads but is that what you need on a desktop? The write process with RAID 5 is slower than normal.

I'm sure additional disk I/O performance is nowhere near as critical as you think it is in a desktop. Spend your money on CPU and Memory in a top notch board of course. You'll reap far more benefit from that than you will with a crazy disk sub-system or an aftermarket MAF.


BAH!!!! i almost have enough!

maybe next check i can send in my throttle body to RVM for boring and see what additional gains i can get from that...should be ~7hp and ~10ft/lbs

either that or i am gonna build a wicked SCSI based desktop computer...i scored a 4ch U160 card for 44 bucks...160MB/s times 4 channels supporting RAID 5...i bet i max out my computer's PCI bus with the cheetah drives i wanna run :thumbsup:

codewize
08-08-07, 11:46 AM
I want proof. I want real number with and without. If one of you has one of these things I'll be happy to dyno it for you. I have an appointment for next week.

Send it to me, I'll do the dyno and send it back. If it does anything at all I'll buy one. I can guarantee you there is no more air flow as far as volume goes.

There was a guy on here who had a Granatelli for $150


Jet MAFS for $275 is a steel.......I baught mine when they were first available last year....paid $385......They definetly give you a little more airflow, not to mention they read signals quicker than the stock MAF....

fubar569
08-08-07, 10:24 PM
Screw SCSI. Save the cash and go for cooler, faster, more readily available SATA 300. And why would you put a performance degrading RAID 5 in a desktop?

RAID 5 has fast reads but is that what you need on a desktop? The write process with RAID 5 is slower than normal.

I'm sure additional disk I/O performance is nowhere near as critical as you think it is in a desktop. Spend your money on CPU and Memory in a top notch board of course. You'll reap far more benefit from that than you will with a crazy disk sub-system or an aftermarket MAF.


don't you mean SAS? (Serial Attached SCSI?) or the new SATAII 3.0Gbps? either way, more readily available? SCSI has been around for a long time...long long time...Parts can be had ANYWHERE for CHEAP now...especially for U160 or U320...

The drives themselves are also built to much higher tolerances. Performance? of course its better...15k RPM and 3-4ms seek time compared to 8-9ms and 7200rpm for anything but a raptor, and even there SCSI holds an advantage (slim, but it exists)...SCSI is also less system dependent than SATA...meaning the speed of the system has much less of an impact on HDD performance with SCSI as does SATA...

I basically am looking for ultra reliability and also blazing read speeds...something you pretty much can only get a good mix of if you use some sort of RAID array. i've played with everything from software RAID...to RAID 0 using 2 and 4 hard drives before but not with mission critical data of course...i loved the responsiveness and there was hardly any lag to do anything. RAID 5 will offer more security and still allow a big performance boost over 1 drive.

As far as spending more money on better CPU and RAM vs a disk subsystem...see argument above. SCSI is much less CPU and/or system dependent than any other solution. However i have also had the pleasure of building a Dual Athlon XP - MP rig, overclocked to 2.34ghz with 1.5GB RAM and a 4 Drive RAID-0 array (using IDE)...more than any home user would ever need...actually wound up selling it due to it being too much computer...but i learned some nice lessons with that system...

1. check your water loop for debris before filling and starting system :thepan:
2. USE ONLY NAME BRAND QUALITY PSU's - another :thepan:
3. That a disk subsystem is at least as important of a consideration as CPU/RAM/etc...and i would have loved to see that system with a full SCSI RAID setup...

U160 is a step off the game but the controller is a quad channel and supports 60HDD's...plus the 44 dollar price tag? can't bead that with a stick! - invest a couple hundred into a set of nice Cheetahs and put them each on their own channel and all of a sudden you have a retarded fast disk subsystem to match all that high performance equipment you have (CPU/RAM/Board/ETC)...

Bottom lineis the system can only ever be as fast as the slowest part...that part...is the Disk Subsystem...

EDIT: just looked into some PCI-E areca cards with SATAII drives, Raptors, etc and such on them...hellz yeah...daddy likey...
however i will still be bottlenecked by PCI...ifi happen to get a mobo with PCI-E you can DAMN well bet it will have an areca in there...

codewize
08-09-07, 11:07 AM
OK. Yes I was referring to SATA-II

SCSI has been around for years but is nowhere near as reliable. SCSI is designed to be in a fault tolerant array where drive can be replaced frequently without data loss.

Performance wise SCSI is less CPU dependant but again, your desktop system isn't performing millions of simultaneous reads and writes like a server could be.

Desktop drives however are far more dependable, at least the good quality drives are.

PSU, absolutly. I buy very high end PSU's. Everything in the system relies on the output of that thing. The PSU can have a very strong influence on system stability.

PCI-E is pretty fast, at least for video it is.

I'm not disagreeing with anything you've said I'm just adding / rambling about it some more.

fubar569
08-09-07, 04:45 PM
OK. Yes I was referring to SATA-II

SCSI has been around for years but is nowhere near as reliable. SCSI is designed to be in a fault tolerant array where drive can be replaced frequently without data loss.

Performance wise SCSI is less CPU dependant but again, your desktop system isn't performing millions of simultaneous reads and writes like a server could be.

Desktop drives however are far more dependable, at least the good quality drives are.

PSU, absolutly. I buy very high end PSU's. Everything in the system relies on the output of that thing. The PSU can have a very strong influence on system stability.

PCI-E is pretty fast, at least for video it is.

I'm not disagreeing with anything you've said I'm just adding / rambling about it some more.

It's all good...nice to see a fellow computer nut on a car board...

i would love to see some numbers on a MAF...if even its a couple hp i'd do it along with the TB and intake swap that i plan on...im thinking it MIGHT be like something else...where you might have to have other supporting mods before any sort of MAF swap will be of any substantial benefit...like the cobra guys that have outrun the stock MAF and need to swap...they also have a TON of other mods

codewize
08-09-07, 09:09 PM
I've heard that before too.


where you might have to have other supporting mods before any sort of MAF swap will be of any substantial benefit...like the cobra guys that have outrun the stock MAF and need to swap...they also have a TON of other mods

msta293412
08-10-07, 08:11 AM
Guys, Im telling you from experiance....you dont need that many other mods for the MAF to be benificial......I had and exhaust, and a modded air box, that would be ideal.....it does give you an edge.....and now there so cheap......

codewize
08-10-07, 08:56 PM
Unless they're larger in diameter, which they're not, they can not flow more air. Additionally the MAF doesn't do any reading. It's simply a sensor monitoring the air mass or volume of air passing over it at any given time. The frequency of the readings or samples is controlled by the PCM. The sensor is sensing all the time.


They definetly give you a little more airflow, not to mention they read signals quicker than the stock MAF....

msta293412
08-11-07, 08:47 AM
Wait a minte CODEWIZE, maybe you should look at the JET MAF , I dont know about the GRANNATELLI, but the JET IS bigger diameter, and it does sense air flow AND temperature....the more air goin through there the unit sends signals to the PCM, the COLDER the air going through there, the unit sends signals to the PCM to increase spark timing. The unit sends these signals at a faster rate than stock....those are all factors for some improved performance......

fubar569
08-11-07, 12:25 PM
Wait a minte CODEWIZE, maybe you should look at the JET MAF , I dont know about the GRANNATELLI, but the JET IS bigger diameter, and it does sense air flow AND temperature....the more air goin through there the unit sends signals to the PCM, the COLDER the air going through there, the unit sends signals to the PCM to increase spark timing. The unit sends these signals at a faster rate than stock....those are all factors for some improved performance......

wait wait...if these sense temp too...whats the purpose of the upstream IAT in the airbox of mine?

Edit: nevermind...it seems they dont list a compatible MAF for my car...but earlier i swear i had it figured out by crossing GM numbers which one would work...i'll have to look it up....or abh...forget it...lol

edit2: FOUND IT. Use corvette equivalent for year of N* motor

codewize
08-11-07, 04:26 PM
If the MAF is larger then the entire plenum would have to be enlarged to be able to have any effect.

And again the MAF only senses the temp and the air mass. It does not SEND the signal. the PCM samples the readings from the MAF at a predetermined rate. the MAF has no control over that frequency. So yes it does SENSE those reading but it doesn't' send or receive anything. I also believe that it's been proven that the lack of flow straightener in the aftermarket MAF's has a negative effect on performance.


Wait a minte CODEWIZE, maybe you should look at the JET MAF , I dont know about the GRANNATELLI, but the JET IS bigger diameter, and it does sense air flow AND temperature....the more air goin through there the unit sends signals to the PCM, the COLDER the air going through there, the unit sends signals to the PCM to increase spark timing. The unit sends these signals at a faster rate than stock....those are all factors for some improved performance......

Submariner409
08-11-07, 05:55 PM
:rolleyes: I have, on the workbench in front of me, a 2002 OEM Cadillac STS Vin 9 MAF. Next to it is a JET Aftermarket replacement. Electronically, resistance and oscilloscope 1 kHz sine waveform, they are identical. The IT thermistor at the edge of the casting is the same unit, with the same resistance values. PHYSICALLY, there are ONLY 3 differences, including the assembly itself, because each bears the same mold number on the ear next to the multipin connector. 1. The JET has no flow straightening honeycomb screen. 2. The JET has no airfoil turbulence reducer upstream of the sensor mount wires. 3. The JET has two assymetrical milled ellipses through the center aluminum mount casting which would theoretically increase maximum airflow by some unspecified value. Neither sensor is capable of actively generating any signal whatsoever. All electronic components are passive, and depending on the PCM sample rate, serve solely to alter resistance in response to temperature and airflow. Each unit was subjected to the same 75 mile test run in the evening of 08/10. Absolutely no change in performance or gas mileage was noted, with 2 runs to 110 mph at the same locations each trip. (It helps to have a wife with a CB watchin' Smokey) I choked the gas tank with 3.5 gallons of Texaco 87, beginning with full, after each run. I have thrown away $276 and change. The CORSA was worth the time and $$$. The MAF is not. (My opinion.....)

codewize
08-11-07, 06:48 PM
Oh look, someone else who's done the homework before wasting money.

And FUBAR569; the IAT was moved inside the MAF in 2000. Prior to that the IAT was in the airbox and the MAF was located at the TB. 200+ the MAF is located at the airbox outlet.


:rolleyes: I have, on the workbench in front of me, a 2002 OEM Cadillac STS Vin 9 MAF. Next to it is a JET Aftermarket replacement. Electronically, resistance and oscilloscope 1 kHz sine waveform, they are identical. The IT thermistor at the edge of the casting is the same unit, with the same resistance values. PHYSICALLY, there are ONLY 3 differences, including the assembly itself, because each bears the same mold number on the ear next to the multipin connector. 1. The JET has no flow straightening honeycomb screen. 2. The JET has no airfoil turbulence reducer upstream of the sensor mount wires. 3. The JET has two assymetrical milled ellipses through the center aluminum mount casting which would theoretically increase maximum airflow by some unspecified value. Neither sensor is capable of actively generating any signal whatsoever. All electronic components are passive, and depending on the PCM sample rate, serve solely to alter resistance in response to temperature and airflow. Each unit was subjected to the same 75 mile test run in the evening of 08/10. Absolutely no change in performance or gas mileage was noted, with 2 runs to 110 mph at the same locations each trip. (It helps to have a wife with a CB watchin' Smokey) I choked the gas tank with 3.5 gallons of Texaco 87, beginning with full, after each run. I have thrown away $276 and change. The CORSA was worth the time and $$$. The MAF is not. (My opinion.....)

msta293412
08-12-07, 08:59 AM
The screen in the stock MAF, contrary to popular belief, is not an "air straightener" it is actually a last ditch effort to filter larger particles that may have gotten past the air filter (factory precaution). Second, the MAF, does directly control how the car runs, just unplug it, and try to turn the car on, you'll see what I mean. The INSIDE diameter is larger, than stock, and yes the factory MAF is a choke point......My buddy got one for his vette, and did get a DYNO'd improvement.....That is why I baught one........Just for the record...as a tool, I had a g-tech, when I first baught my car(stock)...ran several 0-60's..contantly averaging 6.8-6.9.......I then did the exhaust(corsa specs by Magnaflow) K&N drop in, w/moded air box, and JET MAF.....did more 0-60 runs, same temp. same rd, etc....after all mods mentioned...ran consistant 6.0-6.2....Id say the mods I did were beneficial, and I did notice a difference with the MAF......Maybe you need the other mods to go with it, as someone else on here has suggested......I do respect all opinions stated on this thread....Im not the end all be all..... ;-)

Submariner409
08-12-07, 12:24 PM
:confused: msta293412....I believe you are seriously mistaken in your MAF post, above ^. As I stated, both the OEM and JET units bear the same code on the fiberglass reinforced (Marelon) body, I.E. >PBT-(GF+M)30< . (Made by the same factory ???) The inner diameter of EACH unit is 3 1/2" (89mm). The so-called "particle screen" is, in fact, a 1/4" deep honeycomb extrusion airflow straightener, exactly the same in design and principle as some wind tunnel components. Any other differences are noted in my post, above ^. ....Of course the MAF affects engine performance - it is a PASSIVE sensor - and must be plugged in to control temperature and flow voltages by changing resistance in 3 circuits, which is read by the PCM at 1kHz frequency. If you further read my threads, you will find that I DO run a CORSA system, and I DO utilize a highly altered "stock" airbox and inlet from inside the left fenderwell as opposed to behind the headlight assembly. You state that you did several runs after "exhaust, K&N, airbox, JET MAF" installed. If that's true, you have NO way to tell which individual "mod" contributed to better or poorer performance. (As an aside, the throttlebody on these vehicles is somewhat less than 80mm, w/o butterfly, so an upstream 89mm tube presents no loss of airflow at WOT.......) At anything less than WOT redline, these discussions are moot due to low airflow requirements......Take a look at the 2 attached pictures in my above post.

codewize
08-12-07, 01:16 PM
msta293412; I think you've been talking to people who have you believing things that just aren't true. I didn't say you could unplug the MAF nor did anyone else. What I said was that it doesn't SEND the signal. It's a passive sensor that provides snapshot readings on demand from the PCM.

I don't know how else to say this but get over it, you're wrong and so far at least as far as the N* is concerned there is no proof anywhere that these things provide any gain at all.

The screen IS in fact an air straightener. That is not common belief, it's fact coming directly from a Cadillac power-train engineer. The statement about last ditch effort to filter large particle is ridiculous.

The straightener is designed to put the airflow into a pattern that is best suited for the intake plenum design. Additionally it maximized volume by organizing the airflow allowing for maximum mass in the space provided.

At this point even if you could post dyno results I wouldn't believe them. I told you, I'm going to the dyno Tues night. If you have one of these MAF's send it to me and I'll get you numbers. If not then stop arguing about it until you have proof.

As far as you're bottleneck theory goes, the ONLY bottleneck in the N* air flow is the front to rear crossover in the exhaust.

msta293412
08-14-07, 08:11 AM
CODEWIEZ, didnt mean to get you guys all bent out of shape....You, unlike SUBMARINER, seem to just not want to hear it.....SUBMARINER posted a very educational, yet civilized argument, my statements, even though you dont like to hear them, are true to me......Im sorry if I obtained gains from the MAF, I really am. I respect all your opinions (especially SUBMARINERS)....I will post before and after dyno results, from my freinds vette.....If it works for the vette, why would it not work for the STS?....because you dont want it too. Even though I have taken all your posts to heart, fact is, If they didnt work, all the aftermarket MAF makers would be out of bussiness.....

codewize
08-14-07, 09:12 AM
It's not that I just don't want to hear it. I'm posting factual information that I do not personally hold the proof on. I'm basing my statements on proof that I've seen from reliable sources such as SUBMARINER's.

Several after market MAF makers have been sued for false claims and I believe if you do some research Granatelli was one of them.

The Vette has a completely different setup than the N*. That's comparing apples to oranges. Although I would still like to see the data. Either way you're being show that there is no electrical difference and very slight if any physical difference between the 2. You're being shown that the theory of faster data is completely false and hold no weight at all. What more proof do you need to realize that they're just a money making snake oil.


CODEWIEZ, didnt mean to get you guys all bent out of shape....You, unlike SUBMARINER, seem to just not want to hear it.....SUBMARINER posted a very educational, yet civilized argument, my statements, even though you dont like to hear them, are true to me......Im sorry if I obtained gains from the MAF, I really am. I respect all your opinions (especially SUBMARINERS)....I will post before and after dyno results, from my freinds vette.....If it works for the vette, why would it not work for the STS?....because you dont want it too. Even though I have taken all your posts to heart, fact is, If they didnt work, all the aftermarket MAF makers would be out of bussiness.....

msta293412
08-14-07, 10:11 AM
Fair enough.....we have a difference of opinion.......

jadcock
08-14-07, 01:26 PM
I just wanted to add that there was a discussion on Caddyinfo.com a LONG time ago, back when "the" GM powertrain engineer frequented the forum. The discussion was specifically about removing the airflow straightener ("screen") from the MAF sensor to improve flow. He stated in no uncertain terms that it was placed there for a reason, and in particular, that reason was to provide a "clean" airflow signal to the MAF. He said that without that airflow straightener in place, there was too much turbulence inside the MAF and that the quality of the signal from the MAF was reduced. He echoed the same sentiments as some on this board -- without other changes in the intake and exhaust stream, using a different MAF sensor would be inconsequential.

I do agree with what someone said above -- if the MAF sensor is installed amonst other mods...or at least if the only data points are "stock" and "MAF-sensor-along-with-some-other-stuff", any conclusions drawn about the success of the MAF are anecdotal. I don't think anyone can conclusively say the MAF didn't achieve any gains (although that's what comparative reasoning would suggest). But I also don't think anyone can conclusively say the MAF DID achieve any gains either. When more than one variable is changed in an experiment at one time, the results of said experiment can't be used to suggest anything about the change that either variable acheived.

msta293412, it would be interesting to know if you could get a reliable performance REDUCTION if you installed the stock MAF sensor in place of your aftermarket one -- and left all the other modifications in place. You said your car now runs 6.0-6.2 according to your G-tech. I don't think the performance difference would be great enough to tell a difference given the precision (lack thereof) with a G-tech, but who knows. You might even find a 5.9 run or two thrown in there if you switched back to a stock MAF. :)

msta293412
08-14-07, 05:46 PM
OUCH!..JADCOCK...that last jab about getting a better 0-60 time with the stock MAF kinda hurt. Just kidding :-). I understand where you're comin from....I would try but I sold my stock MAF on E-bay.....

Submariner409
08-15-07, 02:14 PM
:eek: This is my last 2 cents worth......AFTER I changed back to the stock MAF I pulled the smaller JET sticker off the aluminum rectangle on the back of the interface housing of the aftermarket unit. Something had been milled off the aluminum casting. A dab of UV dye penetrant and a little darkroom work disclosed the word "DELPHI" in the grain of the casting. Same as the OEM unit. I deduce that JET has not electronically modified the unit (it's sealed, permanently) but has removed some parts by mechanical means and milled a couple of holes, ostensibly to gain "increased airflow", but for what reason? The OEM unit will already flow way more air than a 281 C.I. engine can use, even at WOT. As before, I threw away $276. (BTW, you can also see where the airfoil has been milled out of the plastic case, after the aluminum bridge...)

codewize
08-15-07, 03:04 PM
Very nice work. I tried to give you rep again but it wouldn't let me :) I learned that technique while touring the NYS Forensics facility in Albany. They were talking about people who think they're clever by filing or grinding the SN off of weapons. Little do they know...


:eek: This is my last 2 cents worth......AFTER I changed back to the stock MAF I pulled the smaller JET sticker off the aluminum rectangle on the back of the interface housing of the aftermarket unit. Something had been milled off the aluminum casting. A dab of UV dye penetrant and a little darkroom work disclosed the word "DELPHI" in the grain of the casting. Same as the OEM unit. I deduce that JET has not electronically modified the unit (it's sealed, permanently) but has removed some parts by mechanical means and milled a couple of holes, ostensibly to gain "increased airflow", but for what reason? The OEM unit will already flow way more air than a 281 C.I. engine can use, even at WOT. As before, I threw away $276. (BTW, you can also see where the airfoil has been milled out of the plastic case, after the aluminum bridge...)

msta293412
08-15-07, 09:15 PM
WOW....SUBMARINER, if thats true, I will have to take it like a man wont I? It very well could be that all my other mods made the difference, and the MAF was a placebo effect......I hope CODEWIZE will see I can be reasonable......Very nive observation SUBMARINER....

codewize
08-15-07, 11:18 PM
Hey it's all good. I was just trying to shed the light. I'm a man of proof and I've seen and heard a LOT of proof against them and nothing solid at all to support them.

There are many people like yourself that say I saw or my buddy did BUT how many people have real hard proof.

This is the soul reason I'm dynoing my car. I want to see what the Volant CAI gives us. No more speculation. I want to see what AJ's tune gives us, no more I think or it would, or I did this BUT. None of that crap. I'm coming home with solid real numbers one way or the other.

That's all. I wasn't trying to be a bully or anything, I just want proof when people make claims.


WOW....SUBMARINER, if thats true, I will have to take it like a man wont I? It very well could be that all my other mods made the difference, and the MAF was a placebo effect......I hope CODEWIZE will see I can be reasonable......Very nive observation SUBMARINER....

msta293412
08-16-07, 07:54 AM
Definetly agree with ya there code......Im looking forward to you're numbers........By the way just wanted to clarify, I noticed the last sentence in my post was supposed to be "very NICE observation Submariner" NOT "nive" Didnt want people thinking I meant nieve(if thats how you spell it) Anyways ......