No Juice

iTrader: (11)

Since the search button sucks right now.....

The car has put down between 530 and 570 the past few times on the dyno. We think the stock MAF is causing it to go slightly lean at the end of the runs. So I have few questions

1) What are the limits of the stock MAF? I thought I read somewhere that we are lucky to get 500rwhp before is maxes out, most likely it maxes out before that.

2) What are the numerical limits of the Stock MAF? in grams/second or hertz

3) Will a bigger MAF like the SLP 85mm one help the situation or not? What about the LPE 100mm, I think they use it on their TT Vette?

SonofaBish

iTrader: (5)

I think i've seen several times that the stock MAF maxes out around 8psi give or take... so yes, you are likely flowing too much air for it to meter...

Slowhawk

iTrader: (12)

And just tune in the PE table to make up the difference.

No Juice

iTrader: (11)

Do you guys know if the stock MAF maxes out at 512g/sec or is that the SLP MAF?

Sounds like the LPE 100mm has the same range of 512g/sec, that horseshit!

Jake@EPP

Its the same range, just more resoloution. Just like the ford mafs that are 0-5v, they are still 0-5v, BUT it is more defined in the range.

onfire

iTrader: (17)

512 is not the maf. It's a hard limit in the computer. You can use a 1" maf or a 10"maf and the computer will only read to 512 flow....now which maf causes a pressure drop is another story.

Zombie

iTrader: (2)

Good advice and actually works pretty darn good

I would think it's possible to play games with a stock maf and a frequency divider and then alter some fuel parameters to trick the ecu.

Someone can double check me on this but if you killed the measured mass flow vs frequency by half and halved your injector size you could play some games. I.E. 512gms/sec now = 1024 gms/sec and your 60lb/hr injectors are entered at 30lb/hr injectors. Don't try this, it's just an theoretical example. The stock maf will run out of resolution at some airflow point and become unreliable.

bowtieman81

iTrader: (35)

Is it possible your fuel system is not up to par? What setup are you using?

I was told you can tune a maxed out MAF for more hp than what you are making. The previous owner of my incons ran a stock MAF setup to over 700 rwhp.

onfire

iTrader: (17)

You can but it's dicey...you lose maf control around 640 engine hp and from there on it's all RPM vs PE...It works...I ran a year like that in the 9's but you better not get any boost spikes....or boom.

HUGGER ORANGE SS

iTrader: (2)

Stock Screened Maf here Running 742RWHP 726RWTQ.. w/15psi

the Maf Maxes out at about 4000 rpms. Just all the VE and PE Tune from there..

I would run Speed Den only, but due to the extreme altitude changes were faced with up here, I felt the MAF was needed. Also running the Stock MAP sensor too

Clint

No Juice

iTrader: (11)

I doubt it, we converted the f-body fuel system to a 97-98 vette return style with a walbro 255 and Kenne Bell BAP. We haven't messed with the PE tables yet so thats next on the agenda.

Thanks for the help guys

hellbents10

iTrader: (10)

Sorry but that makes no sense at all. You are using PE to fuel and yet you say you are worried about altitude changes.

HUGGER ORANGE SS

iTrader: (2)

I understand where your coming from.. At WOT the tune is what it is, Safe and locked in with the PE.. But I use the MAF for basic Streetability for the area I live in.. Denver is 1 mile high, the altitude changes between 4000 feet to 12000 feet when your in the Mountains, not to mention the density altitude changes on a daily basis. As much as I street drive my car, the MAF really helps for daily driving with the major Density altitude changes were faced with..

Clint

Q8CamaRo

iTrader: (4)

627/609 RWHP/RWTQ 12PSI maf tune and yeah my maf maxes at approx 4k rpm range

gametech

iTrader: (1)

Actually, if properly tuned the map sensor handles altitude changes perfectly. I would never put up with constantly retuning PE with a maxed out maf. I would rather take a ridiculous amount of time tuning modifier tables and be done with it over knowing I had an endless lifetime of retuning for weather/altitude changes. To each his own I guess.

HUGGER ORANGE SS

iTrader: (2)

Yep your right.. But with the Streetability of part throttle, city and hywy driving using the stock 1 bar MAP sensor I wanted to keep using the MAF.. Problem I'm facing is the MAF and VE tuning sometimes fight each other from time to time.. No doubt about it it's a pain.. But It's always close to where it need to be.

Clint