Ive been driving my wife's 2000 Altima SE to work the past couple days (shes outta town) and while it is peppy enough, it could be peppier!

It's base HP is 150HP. All I have done to it is add a K&N filter to the stock air box.

I started looking at mods for it... Are there any good mods anyone would recommend for an altima? I see they are somewhat hard to come by and a bit expensive...

Ive found that so far, for $750ish, i can get a CAI, Header and Pulley that gives me 25HP extra, and im not sure on the torque, the pulley i noticed added up 8lbs or so extra...not sure about the other parts... but that seems kind of pricey for such little gain, or is that about all I can expect?

ive not seen any exhaust dyno sheets, so im not sure that's even worth the money since nobody seems to be showing any numbers.

I'm not looking to rice it out, and she would kill me if i made it very noticable (like exhaust or something)... so I was looking for engine mods and stuff.

Also, are there any modded computer chips for these cars? I couldn't seem to find any.

One other thing, I was wanting to lower it just a bit to even it out some and get rid of the bug wheel well gaps. but then i noticed the spring kits said the stock struts/shocks won't handle the newer springs? Is that true, and if so, what is recommended for a lower ride?

I have to be subtle about all this, so she won't notice, but I will know it is there and notice the extra performance when I get to drive it

Any suggestions would be appreciated!
Thanks guys!