Jump to content

Auto taped with and without MAF screen :Results

RedHawk

Recommended Posts

RedHawk Enthusiast

RedHawk

Posted
Posted

Being a former 99Firehawk 10 second F body owner, I have always been a firm believer in the FREE mods.. I know they work from my over 120 dynos on my Firehawk and truck.No to mention over 600 passes at the track and countless hours of ATAP testing.. The reason I bought this 2500 HD is because I love the LS1 gen.III motors.. They are incredible motors.. They flat out love air and a far as I am concerned the more the better..

 

Anyway, I pulled some of my ATAP info up on the truck.. I try ?ATAP every mod seperatly and track test them also..

 

There is no doubt in my mind that the screen removed from the MAF works well...

 

Here is what I found..( I would post the atap info but having site problems right now) So, I will just type it..

 

This is on a 2001 2500 HD 6 litre..

 

First removing the screen will increase timing...This is the main gain I see with the screen removed.. The stock timing sucks on these trucks..At low rpm (2000-3000) is max timing of 22 degrees. Then as the rpm increases to the 5200 ish shift point, it will drop to a low of 13 to 15 degrees at the shift..YUCK! . That is very low for these motors but works well with running 87 octane..For optimium performance , I like to see 29 to 30 degrees.. The HPP3 will give you close to this but I run the tunning with screen removed and get 30 to 31 degrees..

 

My stock L trims were at about 8% and only went up to 10-11% with the screen removed.. I have never seen L trims in this area to ever cause me to have a rich condition or poor performing condition.. After the screen was removed MAF flow rate did increase about 2 lbs per minute..Also showing more air flowing into the motor at WOT.. Furthermore, my O2 reading are damn near perfect in my mind at .860 to .875.. Timing increased a peak of 2 degrees at low rpm but the whole average timing went up about 4 to 5 degrees throughout the whole rpm band.. SO, no doubt the screen is well worth the performance for a cheap free mod...

 

I have usually found that the motor will run a tad leaner with MAF porting or screen removing , due to changing the calibration of the meter..In other words you are letting some un-metered air by your MAF..As my 02 reading show , they are still well within good running parameters.. * I do not recomend de- screening if you run DRY NITROUS though..

CMNTMXR81 Senior Enthusiast

CMNTMXR81

Posted
Posted

I too have removed the screens from the MAFS on everything I own.  I can't say I noiticed more timing, but I noticed sharper throttle response due to the slight increase in the air speed not being restricted and straightend by that screen.

 

What you noticed at around 5200rpm before the truck shifted was the "torque management" in our PCM's that back off timing before shifts.

 

I never thought to check my LTrims for the MAF screen.  I've only rreally checked the LTrims when I was trying to get my programming from Ed Wrong and Steve Cole to see if I were running too rich or too lean.

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Latest Articles

  • Posts

    • Chuck FB
      2 speed transfer case optional now?

      By Chuck FB · Posted

      Yes, and also pulling heavy trailers or a large camper up steep grades as well as descending grades such as the more rustic off road camping locations and using engine braking with that low gearing as well as soft ground can just suck the power . I realize pickups these days tend to have an over all lower first gear ratio compared to automatic transmission pickups from years back so that has helped a lot in its ability in high range but there comes a point if in four wheel drive the torque runs out at the wheels, certainly with a gas engine. They don't put two speed transfer cases on pickups for a cool factor, they have a function if one needs that massive torque to the wheels that high range can't deliver. 
    • Grumpy Bear
      Grumpy Bears 2015 Silverado 2WD

      By Grumpy Bear · Posted

      Notes 7/18/2026   3,400 miles on this batch of Mobil 1 Euro 5W40 since the GDI pump replacement. Alcohol runs very clean when ring seal is tight and the sump isn't getting hosed with fuel. Checked oil level at fill up today as is my practice and grabbed a white Kleenex to look at the color. What color?  I was going to change it but.....  
    • Another JR
      2 speed transfer case optional now?

      By Another JR · Posted

      4 low is really nice on steep boat ramps. 
    • Chuck FB
      Gas Prices

      By Chuck FB · Posted

      Interesting, I suspect I would have fueled up in Lee Vining as the day prior I would have filled up either in Laughlin or near there and maybe again before I entered Death Valley and once out the other side late that evening as I kept on driving into the night up near Lee Vining. Next morning I most likely fueled up in LV before heading over Tioga Pass into ( as I refer to it as "Yose .... Mite" 😁 ). And again that was 19 years ago but the price then must not have jumped out at me like the 5 bill a gallon theme of nutty cult hippy country Big Sir or head so far up their rear Aspen. I'd be curious to know where the highest prices are in the lower 48, I probably would not be far off to guess somewhere in Cali forn ie. Coldfoot and Prudhoe bay may have those prices beat but that is a whole other world up there and when prices are more normal elsewhere that is about what they can be up there I believe in no mans land. Anyway interesting that the 395 corridor is hosing people and the thing is, its tourist season and its not like there are a lot of competition options when driving up that highway from what I could see. Yup, big ole Boaterhomes and various other RV's ahead and behind me at the Yosemite entrance gate and they have to get their fuel somewhere.  
    • Atlas
      Gas Prices

      By Atlas · Posted

      Those can be high, as well as the big California cities. The ones that will pop your eyes out are the 395 corridor on the Eastern side of the Sierra Nevadas. Lee Vining, $7.19 for regular and $8.89 for diesel is what the Google said right now.

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...