Absolutely - install a decent intercooler such as the KL Racing, stock will heat soak quickly and is also restrictive when looking at any decent hp gains. Own a 1994 945T that has one and could not be happier, fits right in with no modifications required.
From there I suggest the early ( 1992 -94 ) 960 3" MAF, I used couplers found on Ebay to retain the stock airbox setup ( good for around 300 hp ) so no need to modify ( cone filter etc. ). Beyond that I used green top injectors from an S 60R ( need to bypass the injector ballast resistor ), IPD camshaft, 16T turbo with 15G exhaust housing to maintain the stock down pipe though you can get a correct 3" version to fit the 16T from MKM in Sweden. One should get better flow using either the straight or angled exhaust housing of course, the 15G one is more restrictive but was a simple bolt on.
I also use insulated intake manifold gaskets to reduce heat ( makes a difference ) and an early 960 ( pre 1995 ) oil cooler that mounts under the lower rad support, one needs the early 740 oil filter housing and water pump return pipe with that and custom made oil lines. Not necessary per se but I dislike the oil / coolant heat exchanger Volvo used and the short hoses, one less issue with coolant leaks, especially into the oil and it does happen.
You can have Stoni in Germany make custom mapped chips for both the 2.4 LH ecu as well as EZK if desired ( more advance ). He is well versed in the Bosch LH system and knows how to make it work well. I had the 16T installed without doing much else and the increased flow had the stock ecu hitting fuel cutoff so going to the 3" man and chips is a must to really get anywhere. Stoni uses the boost solenoid from the 850T with a small board that controls boost output to 13 psi but one can easily increase the threshold, it mounts anywhere and only use a few wires to connect. I never installed it ( yet ) as I have a basic manual boost controller.
chipsfrb.html
I am guessing somewhere around 250 hp, though I also have a 2.5" exhaust and gasket matched the exhaust manifold where the turbo mounts as it is restrictive and can be opened up a good amount, one of the reasons they are prone to cracking.
Once you increase hp to around 200 + it is a good idea to invest in a reinforced rear sub frame as well as BNE adjustable torque rods. It is a weak link in the rear suspension design. I also added late 960 reinforcing plates for the front control arms. Upper and lower chassis braces are a plus along with IPD sway bars. No use having decent power without a well controlled suspension.
I am probably missing something - my 945 is an automatic and so far the transmission is surviving but then I do not do things like hard acceleration from a standstill. The extra power output is great for merging on the freeway and simply having fun at times, car cruised easily at 140 kph.
If you have any questions just ask. Beyond this are larger valves in the head and there are other camshafts available from KL Racing etc.
