eh, no.

the UR pulleys can cause problems because they remove the harmonic balancer on the crank pulley - okay, I'll give you that, that is bad for the car...and could reduce power by basically ruining it.

the AEM pulleys however, and any pulleys that are ONLY p/s and alternator pulleys....will do no damage. ESPECIALLY the p/s pulley. The alternator pulley could cause horsepower loss only if your electrical system is extremely taxed or performing poorly, otherwise it doesn't really do a heck of a lot to anything.

You'll gain a little horsepower back, but it's really no more than 2-3hp in any dyno test I've ever seen.

As for the former advice, regrinds can cause problems w/o properly upgraded valve springs - unless the regrind is very mild, in which case, a lot of companies will also hard face them, which causes the cam to be weak, and in some cases cause the augmented lobe to break or become damaged from the different metals moving apart. The only "100% safe" way to increase cam profiles is to make or purchase a billet camshaft. Great idea for power increases, but it's no safer than any other mod.

The port and polish, without proper fuel modifications as well as a knowledgable porter, a descently modified engine otherwise, etc, *can* also cause power loss, and problems. An extremely polished head can cause very poor cold starts and other silly stuff, it's all a matter of who does it and why. Also a great mod, but is no more safe.

With any mod though, if done PROPERLY, no problems should ensue other than more wear due to more agressive driving. So yes, those are good suggestions, but it's not something for an amateur to look into without a good knowledgable mentor.

I'm not flaming you 96JDM, just in case you think I am. I'm just stating the "truth". I've been doing this for a good while.

- Nathan