Hehe...your all wrong. During acceleration it will decrease HP and TQ slightly measured at the wheels with a dynojet depending on the drop in ratio. Fbody guys have disussed this for years since the drop was significant due to wide gearing changes. They would always see from 5-7 rwhp and Tq loss accross the board when going from stock 3.42s to 4.10s. The reason is due to the more rapid rate of engine spin up. It takes less time to spin up all the rotating mass in the driveline and engine so therefore more energy is being consumed to acclerate the engines own rotating mass and not transmitted to the wheels though gearing. I have to do a search but I wrote a lil something about this a while back. It was archived on an Fbody tech page. Its a lenghty explanation so im going to find it and copy and paste it here.

*edit*
damn...wouldnt let me copy of the website. So heres a link. Disregard the reply under mine half way down the page...the guy didnt quite get what I was attempting to explain.

http://www.ls1info.com/article.php?sid=167