Forced Induction Superchargers | Turbochargers | Intercoolers

Stock MAF running about 10psi - Problems??

Thread Tools
 
Search this Thread
 
Old Jul 25, 2007 | 02:35 PM
  #1  
No Juice's Avatar
Thread Starter
TECH Addict
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (11)
 
Joined: Jan 2003
Posts: 2,502
Likes: 19
From: Minnesota Corn Fields
Default Stock MAF running about 10psi - Problems??

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?
Reply
Old Jul 25, 2007 | 03:15 PM
  #2  
SonofaBish's Avatar
TECH Regular
15 Year Member
Photogenic
iTrader: (5)
 
Joined: Apr 2006
Posts: 478
Likes: 0
From: Pittsburgh, PA
Default

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...
Reply
Old Jul 25, 2007 | 03:26 PM
  #3  
Slowhawk's Avatar
LS1Tech Sponsor
iTrader: (12)
 
Joined: Nov 2001
Posts: 14,865
Likes: 6
From: Bridgewater,Ma
Default

Originally Posted by SonofaBish
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...
And just tune in the PE table to make up the difference.
Reply
Old Jul 25, 2007 | 05:22 PM
  #4  
No Juice's Avatar
Thread Starter
TECH Addict
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (11)
 
Joined: Jan 2003
Posts: 2,502
Likes: 19
From: Minnesota Corn Fields
Default

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!
Reply
Old Jul 25, 2007 | 05:30 PM
  #5  
Jake@EPP's Avatar
FormerVendor
 
Joined: Mar 2006
Posts: 1,540
Likes: 0
From: Hell AFB
Default

Originally Posted by No Juice
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!
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.
Reply
Old Jul 25, 2007 | 05:47 PM
  #6  
onfire's Avatar
Coal Mining Director
iTrader: (17)
 
Joined: Nov 2001
Posts: 4,442
Likes: 0
From: Virginia
Default

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.
Reply
Old Jul 25, 2007 | 06:52 PM
  #7  
Zombie's Avatar
10 Second Club
iTrader: (2)
 
Joined: May 2004
Posts: 2,498
Likes: 4
From: Las Vegas
Default

Originally Posted by Slowhawk
And just tune in the PE table to make up the difference.
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.
Reply
Old Jul 25, 2007 | 06:58 PM
  #8  
bowtieman81's Avatar
TECH Fanatic
iTrader: (35)
 
Joined: Sep 2004
Posts: 1,660
Likes: 0
From: Maryland/Illinois
Default

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.
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-1

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-2

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo
Old Jul 25, 2007 | 09:20 PM
  #9  
onfire's Avatar
Coal Mining Director
iTrader: (17)
 
Joined: Nov 2001
Posts: 4,442
Likes: 0
From: Virginia
Default

Originally Posted by bowtieman81
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.
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.
Reply
Old Jul 25, 2007 | 10:23 PM
  #10  
HUGGER ORANGE SS's Avatar
TECH Enthusiast
iTrader: (2)
 
Joined: Jan 2004
Posts: 638
Likes: 1
From: CO
Default

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
Reply
Old Jul 26, 2007 | 07:42 AM
  #11  
No Juice's Avatar
Thread Starter
TECH Addict
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (11)
 
Joined: Jan 2003
Posts: 2,502
Likes: 19
From: Minnesota Corn Fields
Default

Originally Posted by bowtieman81
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.

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
Reply
Old Jul 26, 2007 | 08:03 AM
  #12  
hellbents10's Avatar
LS1Tech Sponsor
iTrader: (10)
 
Joined: Mar 2004
Posts: 4,439
Likes: 4
From: Spring Lake, MI
Default

Originally Posted by HUGGER ORANGE SS
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

Sorry but that makes no sense at all. You are using PE to fuel and yet you say you are worried about altitude changes.
Reply
Old Jul 26, 2007 | 09:28 PM
  #13  
HUGGER ORANGE SS's Avatar
TECH Enthusiast
iTrader: (2)
 
Joined: Jan 2004
Posts: 638
Likes: 1
From: CO
Default

Originally Posted by hellbents10
Sorry but that makes no sense at all. You are using PE to fuel and yet you say you are worried about altitude changes.
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
Reply
Old Jul 26, 2007 | 10:01 PM
  #14  
Q8CamaRo's Avatar
On The Tree
iTrader: (4)
 
Joined: Aug 2003
Posts: 188
Likes: 0
From: State of Kuwait
Default

627/609 RWHP/RWTQ 12PSI maf tune and yeah my maf maxes at approx 4k rpm range
Reply
Old Jul 27, 2007 | 01:33 AM
  #15  
gametech's Avatar
TECH Veteran
20 Year Member
Active Streak: 30 Days
Active Streak: 60 Days
Top Answer: 1
iTrader: (1)
 
Joined: Sep 2004
Posts: 4,905
Likes: 906
From: Stockbridge GA
Default

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.
Reply
Old Jul 27, 2007 | 04:57 PM
  #16  
HUGGER ORANGE SS's Avatar
TECH Enthusiast
iTrader: (2)
 
Joined: Jan 2004
Posts: 638
Likes: 1
From: CO
Default

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
Reply




All times are GMT -5. The time now is 11:21 PM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE