I have for a long time wanted to learn how to work on and upgrade my car, but i have no idea where to start. I don't know what parts to upgrade first and where to look for new parts. I was for example thinking about getting a new air intake since my current one is damaged, but i'm not sure what type of intake and where to get it. If anyone has any experience with this and would want to share it would be greatly appreciated. I have a 1994 850 with a 2.4L engine fyi.

 

As to upgrades to the engine, not a lot worth doing to an NA engine short of giving it a fresh tune (plugs, wires, cap, rotor, filters). The factory airbox is actually quite good so don't waste money on something like a cold air intake that promises 10 HP - that's not happening. There's a lot you can do with a turbo engine starting with an ECU tune that raises boost and adds 40 HP. There are some ECU tunes for the NAs but those can only advance spark and change the fuel map but then you'd need to run premium fuel just to get 10 HP.

Where you can invest is in the suspension. 1) heavy duty sway bars make the biggest difference (I did the IPD sway bars on my 850T wagon) but if you do this also do the HD end links. 2) Consider Bilstein B6 shocks and heavy duty spring seats (again IPD sells HD spring seats but you may be able to swap some from an XC70 if I'm not mistaken. 3) If the suspension is worn, time for front control arms which include bushings and the ball joint, then make sure the tie rods are in good shape. 4) you can consider installing after market springs when doing the struts/shocks. There are really 3 choices here a) go with a coil over, which is a spring/shock in a single unit. This is the most pricey option. b) go with a progressive rate lowering spring which has some softness at the ends for ride compliance like Eibachs c) go with a flat rate stiffer spring like HR. Best to choose a kit that matches the shock to the spring and note this will lower the car 1-2 inches so beware of curbs. I kept the stock springs with the Bilsteins and was quite happy with the HD sway bar + shocks upgrade.

Invest in a sound system. Your volvo uses a "double-DIN" sized stereo so there's a lot of options. since your speakers are also 20 years old you can look to size match and replace or find a shop that does custom installs. Check out web stores like Crutchfields to see what's out there that has bluetooth etc. If you own a lot of CDs you can also find units that play MP3s or stream off your phone