Screens in the MAF

[VETTEX2]

Here is the Corvette Fever article taken from page 92 of the April 2004 issue...

The MAF sensor uses a fine wire that's heated to calculate airflow entering the engine. The early MAF sensors could be damaged quite easily and failed quite frequently. The MAF screens were installed to prevent hot wire damage, whether it be airborne debris or a foreign object. The foreign object could be a wrench, a screwdriver, or a finger striking the MAF hot wire when the MAF was not installed on an engine. If the air filter is installed correctly there is no way debris can strike the MAF sensor hot wire. The screen at the front of the early MAF sensor is also there in case the air filter is damaged.

Having the screens cause turbulent air to allow a better fuel mix makes no sense because the fuel is injected directly into the intake port at the intake valve, which is a long way from the MAF sensor screens. The later MAF sensor used on the 94' and up Corvette has a screen at the front of the MAF sensor to prevent debris from damaging the hot wire from the inlet side. There is no screen at the outlet side of the 94' and up MAF sensor, though. If you remove the MAF sensor screens, it will allow additional airflow, the heat sink fins are ground out with a high speed grinder and the screens removed. Removal of the heat sink fins can be tricky, if the hot wire is touched, it can be damaged.

220k miles on my 86 w/o a screen , 115k miles on my C5 w/o a screen and zero failures on either.

 

[EHS]

I asked C4C5Specialist about removing the MAF screen and he said that it could cause damage and actually reduce LS-1 performance. I’ve read that removing the screen can increase HP, but C4C5 said it was not worth it.

C4c5specialist swapped my car's MAF ends in and out enough that he will probably remember.

On that car, back and forth, including numerous dyno runs both ways, screen vs. no screen was worth about 13 rwhp, say 15 hp at the crank (337 rwhp vs. 324 rwhp). No other changes, same dyno, with c4c5specialist monitoring the runs.

The expense is drivability; without the screen there is a stumble between 1,500-2,800 rpm in second, third, and fourth gears. Notice I keep using the present tense; because after all the back and forth, the extra horsepower is noticeable, and I just "drive around," the stumble. Your choice.

 

[redvett]

Hey redvette what is an A4??

An A4 is an automatic trans.

 

[Edmond]

The expense is drivability; without the screen there is a stumble between 1,500-2,800 rpm in second, third, and fourth gears. Notice I keep using the present tense; because after all the back and forth, the extra horsepower is noticeable, and I just "drive around," the stumble. Your choice.

Yes, that even happens to us C4 guys. That happened to me and I switched back to the MAF that had the screens in it. I had one that I purchased from the Vette' junkyard for $40.