After having some work done on the car, I found that the engine and trans are slowly deteriorating and it is really just a matter of time. 1. I was thinking about replacing my engine with the same model, only with the turbo option. 2. I also wanted to change the transmission to a manual when it goes. What kind of work would be involved in these two changes. I have time.

Peace,
Eamon

If your good and have the right tools figure on about 12-15 hours of work. It is a drop in installation. With the engine your looking at replacing the engine harness, the radiator and computer. You have two options salvage yard, or remanufactured. A used Turbo motor will run between $500 and $800 with under 100K miles. A remanufactured motor your looking at $2300 from a private source(1 yr warranty) to $2995 at a Volvo dealer (2 year warranty). The transmission can be had from a salvage yard for M46(4sp elec OD) or M47(true 5sp)$250 to $500. Just remember you need the pedals, consol insert, flywheel, and a driveshaft from a 700 that mates up to that transmission. Autos, M46, M47 all have different length driveshafts. You can use a 240 transmission you just need the transmission mounts, shifter and linkage and a 700 flywheel. A new clutch, throw out bearing, and pressure plate will run under $300. You can use a cable or hydraulic clutch. The cable is $85 to go hydralic it will probably run $500 for needed parts.

That is a big job. Gordon Vos, who posts here as VOS has converted a 1990 NA car to turbo, and has a web site on it. You might search he archives.

To convert from NA to turbo means major wiring changes, replacement of the ECU and EZK, fuel pump(s) and more. You are better off buying another car. It will probably be cheaper, too. If you are not highly skilled at all things electrical, don't start this job.

Sorry, forgot to say it is a '91 740 sedan