Underdrive Pulley

I was wondering if it is possible to install a underdrive pulley myself, and can i install a race pipe by myself. O yea and is the underdrive pulley safe what about the lightend 3sx one?

ive heard those underdrive pulleys are really hit or miss. some people say they screwed over their cars and some say they love it. if anyone knows exactly what sort of problems it could cause lemme know. cuz i see it added in a lot of staged upgrade things but i dunno if i wanna risk it.

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the 3sx lightened pulley has seen a lot of success, i've had it on my car for over a year and a half, and no problems at all. You can install it yourself if you know how to remove the accessory belt, the crank pulley, and then reinstall both. If you can't do it, and if your nearing a 60K tune up, do it while your changing your timing belt. If your mechanic doesnt install it at no extra charge while installing the timing belt, find a new mechanic, cause he has to remove the crank pulley and put it back on anyways.