[Fast Corners]

"I have an 80 euro 911 with a relatively fresh (30K) mile 3.0 in it. It has SS heat exchangers and a BB muffler (great sound). The car runs very strong, especially for a NA car at 5000ft (Colorado)."

I'm assuming that the motor you are talking about is the original motor to the 1980 SC. It is clear that some mods have already been done to the motor but I'm unsure about the injection system you are saying you have below. The original injection system was not mechanical injection but CIS and this makes a huge difference. The CIS system can not handle anything but a mild cam grind whereas MFI can accomodate a wicked cam. Whit that in mind I will address the options you listed.

1 Take the 3.0L out to a 3.2L with new P/C, install cams and ditch the mechanical injection for a electronic injection.
this is a very good option and the power increase you will see by changing the P's&C's will be huge. For a street motor running on pump gas I would recommend 10:1 CR pistons and an "S" or GE 80 cams. Changing the fuel injection to a modern EFI system (like a TEC3) with crank fire ignition will make the engine run more fuel efficiently, generate more power and will accomodate extream elevation changes very well. With a system like this and your exhaust system you should see large gains in HP and Torque.

2 Take the 3.0L to 3.4L, using a 3.2 crank and new P/C - and all the stuff listed in #1. Can the 3.2 crank be run in a 3.0 case.
Similar to the comment on option 1 the additional displace ment will help boost HP and Torques values further but at additional cost. figure atleast an additional $5K over option 1

3 Buy a 964/993 3.6L, sell the 3.0L and do a transplant.
With this option I think all you can salvage from your 3.0 is the muffler. At any rate, a stock 964 motor is only going to give you ~15 to 20 more HP over your current set up. Torque will climb due to the larger displacement and better cams, etc. The 993 motor will give an increase in the range of ~50 to 55 HP with an even broader Torque curve. This is thanks to the better induction, exhaust and vario cam system. I do not recommend the 964 motor since there are some real problems with oil leaks on the early versions of this motor and the HP increase over your moter is not very much for the expense. A 993 motor swap will probably run you around $15 to $18K depending on the condition of it and the expense of converting you car to work with it. This means the oil coolers, electonics, labor etc.

4 Forced induction on the 3.0L - supercharger or turbo?

Wow you are ambitious. HP and Torque gains form this can be astronomical. You are still going to do some work on your motor to get the system to work well. The cheapest way to go would be a low PSI blower. I believe that the kits for these are around $10K but I don't know sing I have not really looked into it. Your motor will take extensive mods to get alot of reliable power out of a turbo set up.

You have some decient options to pick from but for my choice I would go with Option1. The later motors are great but they seem sluggish to me. The massive flywheel keeps them from spooling up as quickly as the should. The throttle response is very slow which makes heal and toe down shifting more difficult than it should be. You can help cure this by going with a Carrera Cup flywheel but that adds another $1.5K to the equation. Finally, an aluminum case 915 is a great transmission but it does have a limit. If you go too radical with your Power increase you may need to consider modifying your Transmission or replacing it with a G50.

Let us know which way you go.