a 6-speed Z with a competant driver should pull on a lightly modded GTP. While we lack top end, they have pull throughout the entire powerband
Here's me and my friend's Comp-G racing an SE-R Altima 6-speed with a Nismo intake and TB spacer. Comp-G had intake, plog, ported mani, 3.5 pulley, tune, catless dp and a few other odd parts. Mine at the time was still pretty much stock minus some minor exhaust work, intake, and a can tune
He pulled on us both. Dude can drive though.
YouTube - 04 Comp-G vs. 05 Altima SE-R
(p.s. I let off at 100 on the last run cause my trans was ****ED)
Second time around my car was down haha. But Comp-G had same mods as above with a few other things I can't remember and SE-R had added a VIS blockplate (removes a butterfly valve in the intake manifold to help air flow up top)
http://www.youtube.com/watch?v=8bFZvZdTEl8