i was told today that puting these stage 3 cams in my 99 si would be an overkill. told me to change the compression. i have an intake manifold 65mm, cai, headers, throttle body, catback. i wil also be installing skunk2 cam gears with the cams. any suggestions would help and i would appreciate.

 

stage 3 cams are very aggressive. and i think the car wont idle as normal as before. and i think u will need to build the stronger internals such as pistons,piston rings, new higher compression head gasket, new stronger valve , valve springs, and retainers..etc and get it dyno tuned afterwards.
i would say stock oem ITR/CTR cams would be ideal for your set up.cause i am running the same thing and it is very reliable and idles at normal.

 

if you daily drive this car you should go with crazyguy's idea.

Find the right oem cam combination to suit you and start there.