Tom-I plugged that same hose early on when I noticed boost going away at the 2-3 shift. I finally coaxed it out of Whipple that it was there to save the tranny. Sure enough a few weeks after plugging it off the tranny started slipping.

The Whipple computer does cause false IAT readings. When I still had mine sometimes it would show -40, sometimes 100+ over ambient. It also messed with the engine coolant temp. My truck didn't start coming around til I got rid of all that crap!

a blow off valve and a bypass valve are substantialy diferent. with a blow off valve the boost has been made and gets bled off but with the bypass the boost is never made. one of the reasons they do this is so the blower uses almost no hp when not under boost, it is a great system.

what tybrine is talking about is whipples atempt to use that bypass valve as a saftey device or maybe even a tuning device. the whipple computer watches the 02's and if it sees a lean condition it will open the bypass and relieve some boost. seems like another good idea to me. mine opened a couple of times, once when my fuel pump was maxed out and another time with a bad 02 sensor. i wouldn't have been alereted to either one of these problems nearly as quickly without that whipple light flashing in my face.

i am not doubting anyones IAT but just to be sure here how did you measure them? prety sure with the radix you would have to insert a probe or somehow move the AIT sensor. i guess the ATI set up is a blow thru on the MAF? so it is acurate?

one last thing, my AIT temps went way high on my truck even though the MAF and AIT sensor was in the stock place(before the blower). i would see as much as 100deg above ambiant once i got on it and i am 100% sure it was a false reading, did i just have a problem or is there some reason for the sensor to read way high when the air really starts to flow?

Ranwalk- I completely removed the Whipple computer. The safety crap never worked right on mine-I could unhook sensors and the little blinky light woudln't come on. Whipple told me that the light was mainly to identify high EGT/lean conditions and that it was calibrated to come on at a O2 reading of 750mv! It would be melted down by then anyway so I took it all off and cleaned up the engine bay a bit. That built in safety stuff is like tq mgt or shift interlocks-produced to protect the general public from themselves.