Maybe but I can't divulge anything yet... but from what I've overheard on wire taps and from what I've seen... er um... I know nothingk! NOTHINGK!!!!!

 

QUOTE:
As far as lids go, if I were going to use any MAF table with my lid (without building one from scratch), I would use a Holden table. I think that the way their intake was designed would more closely match our lids.
QUOTE:

I have a 98 LS1 with all the 'bolt-on' stuff. By 'trial & error' I came up with a 'nice' MAF table.
After switching over to HPTuner in November I came across the 'Holden' MAF table from a 'bin' file.
I couldn't believe how close my MAF 'table' was to the Holden one.
I now use the Holden MAF table as it was better at idle & off idle.

THE HOLDEN MAF TABLE IS JUST AWESOME FOR THE F-BODY WITH AN AFTERMARKET LID & BASIC 'BOLT-ONS'

DAVE

 

sorry to be such a PITA about this whole thing.

 

Thats awesome. I suspected it would work for a long time. I spent hours searching the Internet for pictures of different intake from GM trucks, and other vehicles. I think an S-10 MAF table would be close too, but I could never get my hands on one. The Holden one looked like a winner though. Cool!

 

I have personally watched as a fast 90 setup was swapped to from an ls6/ported TB and they instantly picked up 25 rwhp, with an untouched 85mm maf in place. I would say it works just fine. Is it a max effort configuration, of course not. But that doesn't mean that it is a waste.

 

Yes - the factory meter will output up to 20,000 k/htz but the factory ecms choke at 13000 k/htz. That why i say let EFILive go from there or HPtuner type stuff

 

Well it must have to do with the runner and plenum differences rather than the TB diameter (which is what most people are thinking about with a 90mm setup). It just isn't physically possible that the TB size itself is making more power. Has anyone done a comparison between the Fast 78.. and the Fast 90mm? Are the manifolds the same, minus the TB inlet size?

 

This is basically the case - I agree. it only seems natural that if one is willing to sit there for a while and do all the math they can fine tune anything

 

This statement is unclear and misleading. porting a meter will not change its transfer functions. After it is ported the transfer functions need to be rescaled. GMS never used has to soldier a resistor like SLP or PACE becuase we have the ability to go into the meter and actually change the transfer functions. I can remember when you guys took one of our meter apart and displayed on this site and then proceeded to tell everyone that that person figured it all out. I sat there and could not say a word becuase I did not want to get into a pissing contest where GMS would have to prove otherwise becuase in doing so we felt we would have show a few things that we felt were still secrets. I am alwsy will to give input but not willing to say how we modify meters. Tons have speculated and a few have been on the right track - hell if a few of you got your data together you may have had it. inthe end it is all a mute point now becuase the guy that come to LS1tech IS WILLing to go the extra mile. we still service the guy that wants the extra 10hp with no hassles.

 

At the end of page 5 you guys start talking about adding cold air lids and then talk how they change the way the meter works. a screened meter does not care what is in front of it . The screens do help laminar airflow. Then anothe guys talks about MMFF a ford magazine and how they explained the MAF in depth. A hitachi (or Ford style) meter has liitle to do with the Delphi meter and the way they operate. plus most of the mustangs out there done have a screenin the meter anyways. They are not on the same caliber as a Delphi design

 

Thanks for chiming in Granatelli and clearing some things up.

 

:shrug: I still don't even know what a "transfer function" is.

 

I am sure that the manifold is larger at the TB opening. Runner and plenum size I don't know about though.

The MAF table in the LS1 PCM is the transfer function, at least that is what it was always referred to in the past with older PCM software, ford stuff, and standalones.


I still argue that screened or not whatever is in front of the MAF will change it's relative output. A screen will smooth out the airflow, not redirect a "fast" spot of air from the corner to the resister. GM agrees with me. I also agree that the 04 holden MAF table tested perfect with me and an aftermarket airlid.

 

No offense but thats been obvious to me for awhile. I don't think you guys understand what it truly is. And the MAF tables aren't it. Granatelli has confirmed that.

I have calculated transfer functions before.

Question still remains. How does a lid change the transfer function. Post up the transfer function formulation and show where the airflow is the variable.

Shouldn't be hard since this is "basic stuff"

If I'm wrong, I am more than happy and willing to admit it. But nobody has been able to show otherwise.

 

The MAF table in the PCM has been referred to as the MAF transfer function for many many years by just about everyone. Type in maf transfer function in google and see for yourself. But if you are trying to be technical about it by implying that the actual sensor element doesn't change what they read you would be correct. It is what they don't read that is what we are talking about with different intake configurations, thus skewing as we know it the MAF transfer function in the PCM. "basic"



So how about this new 2/3 bar feature in HP Tuners? I know I am eagerly awaiting as I have customers that would take advantage of it.

 

i still havent head if the SD tune compensates for weather, another_user says it uses the IAT to calulate, so IS THAT SUFFICANT FOR WEATHER CHANGES?

next will the SD tune allo desent fuel consuption for normal driving or will people get bad gas milage switching to a SD tune

those are the main conserns for me.

 

My gas mileage picked up when i got rid of the the MAF.

This may be a trivial question but how does weather affect a sensor that measures airflow (mass airflow to be exact). The way I look at it, is the map sensor and the iat sensor can provide enough resloution of whats going on with the weather.

 

Yes it does compensate for weather, probably based on an internal calculation using the baro reading and the IAT sensor. I do see it drift from day to day but the closed loop fueling will always make idle/part throttle corrections just fine but WOT will always be off slightly. It is fine though, just not as accurate as a car that uses an actual sensor to measure the mass of air.

I noticed no difference in gas mileage between a nicely dialed in SD tune and a nicely dialed in MAF tune.

 

Yep. It compensates. I got excellent gas mileage with my SD tune. Better than when I had my MAF on with my cam by a longshot. Good stuff.

 

Maybe a few of us should change a little of our wording to say "the before and after paths of the intake relative to the MAF change an input to the transfer function".