That little button on the floor

[Vytautas Reipa <vytas@erols.com>]

Hi all. I got in an argument with a friend a few days ago over what the
little button on the floor behind the gas pedal in my 5ks and 5kcst(both
auto) does. I said that it forces a downshift or delays an upshift,
allowing the revs to reach close to the redline. I noticed that every time
I press it, one of the before mentioned things happens. He says that it has
nothing to do with the transmission. Who is right? And what does it really
do? Thanks for any help.

Vytautas Reipa
5ks '87
5kcst '86 rocketmobile.