from Mike Bigus who has a 96 Golf VR6.

I work at Underwriters Laboratories Inc. in the Fire Protection

department.  We have all kinds of temperature sensing equipment

for our fire tests and I used some of it one day quite a while

ago for some very interesting tests.

Standing Idling Tests
Inconel Thermocouple on fully warm engine block beside air box.	190 degrees F
Thermocouple on side of air box closest to engine	190 degrees F
Thermocouple inside air box	95 degrees F
Thermocouple on P-flo closest to engine	185 degrees F
Thermocouple on opposite side of P-Flo furthest from engine	150 degrees F
Moving Tests at 55 mph
Thermocouple on engine block beside air box	135 degrees F
Thermocouple on side of air box closest to engine	115 degrees F
Thermocouple inside air box	80 degrees F
Thermocouple on P-Flo closest to engine	105 degrees F
Thermocouple on opposite side of P-flo farthest from engine	99 degrees F

outside temp 80 degrees F

So there it is.  Draw your own conclusions.

I've been telling people around me for over a year now that

the stock air box with mods is better, not to mention cheaper

but no one listens to Mike...