Advice Please Options

[6G96GT]

First thing, I took off my wheel the other day to get a look at my rotor, anyway the car was in 1st gear (parked, engine off) and the e-brake was up all the way. I noticed though that the rotor moved about 1/4" back and forth even in gear with the e-brake on. Is that normal? My brake will hold me on a hill when in neutral.

Second, is there anything I can do to improve torque or low-end power (without turbo, cams, and supercharger). Would some kind of engine/fuel management or intake manifold work do anything at all to improve it?

Finally, my exhaust is vibrating (very annoying) when reducing speed in every gear (at 2000 rpm, it's the worst). I have the header into a flex pipe into a hi-flow cat (shielded) into a welded resonator into my exhaust. It's definitely not the muffler or resonator and I don't 'think' it's the header. When I jacked up the car and started it and had my friend raise and lower the throttle, I didn't hear any vibration or rattle at all.

This post has been edited by 6G96GT: Jun 8, 2009 - 1:50 PM

[6G96GT]

That's what I mean, I definitely had more low-end before I switched from the stock mani to the header.

Why would a SAFC reduce the engine life? I thought tuning it would be good.