I put my Frankencar in a few weeks ago, and I've noticed that when I go WOT (I have a 98 GXE Auto), it pulls like a train up until the shift, and then there is a noticable pause when it is shifting up. Probably a half-second. Is this normal?

 

I had the same thing...

I just installed an Injen style CAI and when I reset the engine light, I forgot to put the twist to the correct position, so I believe the location of this (which is also the idle control) it was affecting the shifts...I redid the clear service engine light again and it fixed my problem shifting and the SES has not come on like before when it would come back on within a few minutes...

maybe this will help.