What kind of easy, cheap, safe upgrades can I do the my S60, 2004 2.5T, without damaging anything else. I was thinking about installing a blow-off valve and a K&N filter, but im not sure. Please help!

 

I personally am not a fan of K + N filters just because I dont like oiling filters.. just introduces another risk factor.. a drop in filter might give some gain but the restiction is the factory airbox, the only way to really enjoy it is to replace the entire unit with a short ram or cold air intake..
then of course you will want to look into upgraded exahust, IPD ECU retune, some anti sway bars, etc

 

Always drive down hill.

 

Welcome...

1. A BOV will not add any performance benefit to you. As our Volvo's don't produce high enough boost pressure and power there is no reason for one. The stock turbo comes with a CBV that basically does the same thing. The only thing you will get with a BOV is the sound and the possibility of running rich everytime you let off the gas and or shift gear. FYI if your automatic you will only hear your BOV go off after you let off the gas.

2. K&N filters are fine. The oil thing yes it can be damaging to the MAF. Solution is to not over oil them.

3. Nothing is cheap in the Volvo world. To gain any power you have to spend money. That brings up what is your budget? We can help you more if we know a budget. Also a power level you'd like to reach.

My opinion save your money on the BOV and put it towards other mods. Used to own a BOV and it got old real quick and it made my car run rich and leaked vacuum a lot.