Neuspeed TIP and increased EGT

The same day I installed NS TIP, I drove back home from my buddy's place and I have noticed that on a highway (65MPH+) the the EGT was about 150-200F higher than before according to my EGT gauge. I thought that ECU will compensate for leaner Air/fuel mixture, but it doesn't yet. Does anyone with NS TIP experienced the same thing? Someone posted pics of his glowing turbo after he installed NS TIP and 3"DP not long ago, and responses were something like "it runs hotter because it runs more flow". I think it is [email protected]#$%^Sh*T, the key is a leaner mixture and as a consequence higher EGT.