amgalex

Ok so second time i came to the Drag strip in the last few weeks
track elevation 1400ft

Around same temperatures at the strip 70 degrees
my times improved from 14.00 sec 101mph 2.18 60ft, 77mph 1/8mi to:

13,80 in 1/4 mi 102mph ,, 2.18 60ft , 80.92mph in 1/8mi
the only things I did were removed MAF insert, insulated the airbox, installed a potentiometer and overridden the intake temperature sensor by lower read out temperature by 15 degrees F

corrected would be 13.59 at 104.2mph

still seems slow but maybe my 60ft got to improve a few tenth

503C43 ////AMG

Please elaborate...
By MAF insert are you referring to the screen? How did you insulate the air box? please explain more about the potentiometer and intake sensor...

Fabio D

Removing the MAF insert screen is not an option. gets a horrible idle in this cars & the trans shifts has a pretty bad points

Clarify on the potentiometer and intake temps please? gretly apreciated

Fabio Daniel

Schweinhund

+1 MAF screen is to even the flow of inlet air, not protect against bugs!

snooozie

Some bugs might get in to the inlet and course the engine to have rough idling.

billbillw

Correct, sort of. The screen creates turbulence under low flow situations. The turbulence mixes the air and creates a uniform velocity profile. Without the screen under light load you can get laminar flow which has and uneven velocity profile (faster in the center of the tube, slower near the walls). This can cause erroneous readings and screw up the mixture.

Schweinhund

Well said and I submit to you that the screen also prevents vortexing through the MAF at higher velocities.

amgalex

In regards to the MAF screen removal, my observations :
shorts term fuel corrections are a lot more active than with MAF insert in.
I did not notice a rough idle because I already have a pretty rough idle prior the removal (have no clue why)
I would have to test this mod at the drag strip to see if there is more air coming in by recording MAF max readings and by comparing times. For now the screen is back in.

On Potentiometer: Very interesting results. I came up with this idea because our MAF sensors sit right on the throttle body and get heat soaked pretty bad. On a 80 degree day intake temperatures read as high as 130 which would retard timing. The Idea is to attempt to advance timing. So went to local Radio Shack and matched the resistance of the Intake temperature sensor plus 5000k (5k variable resistor)
istalled it by interrupting sensor wire in the MAF plug. Now i can set my intake temps to read as low as 20 degrees F but im running it so it matches the outside temperatures. So if its 70 f outside , intake will read 70, if its 100 outside intake would read 100.
Did a few runs just with gtech and i must say I was surprised by the results but, 0-60 times went down .1-.2 of a second, that's quite a significant increase in power, but i will have to verify this on track. Don't know what exactly the advance in timing would be with even lower readings but for now Im just sticking to ambient temperature match to be safe.
thoughts?

amgalex

Got some thermal wrap from local Home Depo store, the double sided reflective type with glass insulation in between, installed on the bottom of the airbox where it sits on the manifold by using tape.
For now just cut 2 sleves form an old sweater and put them in the intake tubes, looks ugly but il come up with something more creative later

snooozie

Ever thought about getting one of those carbon fiber hood off ebay and have a scoop cut out in the middle for air intake? Would make more sense as the scoop would get mad air to the MAF

amgalex

ever thought about yourself being full of ****?