Boost Reduction with AC on? Options

[Geddes]

It was a fairly hot day today (over 30 degrees celcius) and I was cruising down the highway with the ac on which I don't normally have on.. and noticed that the car was not boosting as per normal..

I know the TSVS setup will reduce boost levels if it thinks its seeing knock, so with the very hot air im assuming it was pulling a bit of boost for that reason, but having the ac system turned on drops the boost even more (I have no actual numbers to give you as I dont have my boost guage hooked up yet), but for comparison, the car with the ac off will peg the boost needle near the top (on a colder day it will hit the plus sign above the top of the guage) but when i turn the ac on, it only makes it to about bar 4 of 6 on the guage..

TLDR version: any one else with a GT-4 with no boost controller installed notice a reduction in boost with the ac on? or is mine just doing something odd..?

for reference, I checked between ac on and off in 3rd gear every time.

[Mr_Tee]

Not too sure, however boost pressure should increase with engine load. Try quick shift to 3rd or 4th with WOT and you should see full boost. Altitude levels may be another factor to consider though.