Relocation of MAFS on Turbo Applications
07-27-2007 | 08:55 PM
#26
TurboTim
Joined: Feb 2005
Posts: 251
Likes: 0
From: San Diego
And you probably remember, Tim, that the MAF/screen issue is about 3 years old now. It is always suggested to use at least one screen in front of the MAF sensor. One thing I was able to do was use a Blitz SUS filter and the MAF didn't seem to mind having no screen in front.
Nobody mentioned it in this thread so I thought I would.
07-28-2007 | 01:38 AM
#27
RotoRocks Powered
Joined: May 2006
Posts: 1,236
Likes: 6
From: Delray Beach, FL
Yes.
Opening and closing BOV will cause a lot of turbulence, which will get you MAF sensor confused real quick.
This makes no difference when using Int-X/Microtech though, as with Microtech you only make use off the intake temperature, which in most kind of useless.
GTAW can you PM me on the details for that MAF flange?
I don't have it inserted anywhere. My MAF is just sitting in the engine bay, telling me how hot it is in there, but I would like to install it just for the cosmetic (complete look) purposes.
Opening and closing BOV will cause a lot of turbulence, which will get you MAF sensor confused real quick.
This makes no difference when using Int-X/Microtech though, as with Microtech you only make use off the intake temperature, which in most kind of useless.
GTAW can you PM me on the details for that MAF flange?
I don't have it inserted anywhere. My MAF is just sitting in the engine bay, telling me how hot it is in there, but I would like to install it just for the cosmetic (complete look) purposes.
07-28-2007 | 01:49 AM
#28
Thread Starter
Apexing at Oak Tree
Joined: Oct 2003
Posts: 717
Likes: 0
From: The Blue, Educated State in the North
Unless someone can show significant advantage over a properly installed and tuned setup with the MAF before the turbo, this doesn't sound like the relocation effort is worthwhile.
And besides air loss from a non-recirculated BOV, the MAF should read the same either way.
I'd rather have screens on the non compressed air stream too.
And besides air loss from a non-recirculated BOV, the MAF should read the same either way.
I'd rather have screens on the non compressed air stream too.
07-31-2007 | 02:01 AM
#29
TurboTim
Joined: Feb 2005
Posts: 251
Likes: 0
From: San Diego
Exactly.You will get much more accuate air metering as you are measuring the air after it gets compressed, goes though the intercooler and piping,etc........The chances of sucking in unmetered air and potentially running lean is greatly minimized.
08-06-2007 | 10:34 PM
#30
Thread Starter
Apexing at Oak Tree
Joined: Oct 2003
Posts: 717
Likes: 0
From: The Blue, Educated State in the North
Tim, another question. Do you use 3.5" piping throughout the system (intake to turbo to intertooler to MAFS to TB)? wondering about the flow implications of not using uniform piping diameter throughout the whole sustem.
08-07-2007 | 01:59 PM
#34
TurboTim
Joined: Feb 2005
Posts: 251
Likes: 0
From: San Diego
Tim
08-07-2007 | 02:21 PM
#35
It has an operating range of 0 to 5 volts.
It idles at 1.16 volts or so and at the torque peak, about 4.5 volts is seen on a 330 HP run, so the earlier estimates are probably a bit optimistic.
08-07-2007 | 02:37 PM
#37
Registered User
Joined: Jun 2002
Posts: 3,086
Likes: 1
From: Misinformation Director - Evolv Chicago
I was under the impression that our MAF is the same model that is used in the STi...
08-08-2007 | 02:25 PM
#41
You have to spring for a Horriba (at $2k) to get something "better" and its "better-ness" is debatable.
08-10-2007 | 12:54 PM
#43
Here is the graph and excel file.
Remember these are averages over a few hundred thousand points.
The high end for Jeff was 4.47 at 38 lb/min of air. So you should def get to at least 45-50 lb/min I would think.
I think the variation would be from either BOV or spooling up, or both. But am not really sure.
Remember these are averages over a few hundred thousand points.
The high end for Jeff was 4.47 at 38 lb/min of air. So you should def get to at least 45-50 lb/min I would think.
I think the variation would be from either BOV or spooling up, or both. But am not really sure.
Last edited by Kane; 08-09-2009 at 05:56 PM.
08-10-2007 | 06:10 PM
#44
Guest
Posts: n/a
Thanks Kane, the graph gives us a good idea on where we stand. It looks like the MAF may be good for about 50 lbs/min.
Right now, at 5-6lbs of boost, I'm hitting between 4.45 and 4.57v at around 8000-8500 rpms with a 60-1 turbo. The plan is to run 9-10 lbs up to redline once I'm happy with the tune at the lower boost levels and slowly progress from there, until either the MAF is maxed or the ignition gives up the ghost.
I've been using Innovate's LC-1 and digital gauge package for about two years. The bung is welded about 3' away from the downpipe and the unit is stilling going strong. I recalibrate it every couple of months just to be on the safe side and overall, couldn't be happier with it.
Right now, at 5-6lbs of boost, I'm hitting between 4.45 and 4.57v at around 8000-8500 rpms with a 60-1 turbo. The plan is to run 9-10 lbs up to redline once I'm happy with the tune at the lower boost levels and slowly progress from there, until either the MAF is maxed or the ignition gives up the ghost.
I've been using Innovate's LC-1 and digital gauge package for about two years. The bung is welded about 3' away from the downpipe and the unit is stilling going strong. I recalibrate it every couple of months just to be on the safe side and overall, couldn't be happier with it.
Last edited by GTAW; 08-10-2007 at 11:20 PM.
08-20-2007 | 11:54 AM
#47
The only issue I see with your premise Charles, is the BOV... I do not know what a vented BOV does to the MAF when it goes. At 29 lbs/min (FI 11.5 AFR), you are somewhere around....260 HP. So 35 lb/min at 12:1 would be well over 300... can't find proof just yet.
08-20-2007 | 12:14 PM
#48
Your assumptions are correct - if at 180 lb/hours of fuel (12.1 AFR), that is 87% more than stock fuel maximum... so given enough air to support it, you could theoretically say that you can make 87% more power than the stock fuel system can handle before the MAF gives out (which is +/- 300 hp?)... semi-educated guess... 561 HP if you were NA (in a perfect world). That is just the MAF sensor, not the engine. And FI, you drop down.