dssur
+1y
the 86 325 (with no letter after the 5) is a low redline high torque engine made for fuel economy. Redline is around 5k and it has a 2:73 rear gear so cruising is easy but acceleration is slow.
You can (and should) buy a performance chip, ebay has them for about 50 bucks. You need to pull the computer (glovebox) and count the number of pins on the eprom before ordering. It TRANSFORMS this engine, to like 130hp and 190lb ft. Another good upgrade is a higher (numerically) rear gear, but finding one isnt easy, you need a 3:07 or 3:23 from a 80's 5 or 6 series, the 3:73 or 4:10 from the 325i cars is too high to keep freeway revs down.
If you just want a driver, chip it. Dont waste money on exhaust or intake or whatever, the chip will make it a torque monster. I know quite a bit about them so hit me up if you have questions.
Oh, and cange the timing belt right away. bad things happen if you dont.