I'm far from an expert, so I can't offer much help, but your post made me curious. Why are you doing this particular swap?
I'm sorry... did you say Tuesday? as in this week, tomorrow? ..and you are asking these sorts of basic questions now? ...I mean, "
NOW?"
Yes, physically they fit and mount the same.
Here's another issue for you to consider: The Tiptronic transmission harness is bundled into the engine harness. If you don't use the 2.5's harness, you will need to tear it apart and rebuild it or find a 2.7L Tiptronic harness.
Know what you are going to do before the shop tries to put the replacement engine in. (Are they experienced and do they have any suggestions about these issues?)
Throttle body: 1998 is actuated by a cable and gives position (load demand) info to the DME.
With the 2001, the gas pedal has a position sensor that gives load demand to the DME, which activates a servo on the throttle body, then a position sensor on the throttle sends feedback to the DME.
My
guess is that the 5.2.2 DME will only work with the cable throttle and the 7.2 DME will only work with the eGas throttle. Programming and wiring will not fix that.
Either DME and throttle set-up will need
custom programming to function
well.
The 12v wire and DME pin 59 is specifically for controlling the flapper valve on the 2.7 intake's second cross-tube with the 5.2.2 DME. I don't think that pin 59 on your 1998 986 DME is going to be active without reprogramming. The engine will run without the flapper. It will have trouble meeting the correct fuel/air mix and have some flat spots in the power curve.
Unless you are ready to pay en experienced, skilled pro to get it all configured, swapping various parts will just be a poor compromise and give less performance than a proper 2.5L engine.
Yes. TC and tranny bolt up, no issues.
That's good planning. Other thoughts: IMS bearing and seal. Cam tensioner/adjuster pads.
My related experience is swapping a 2.7L manual engine into a 2.7L Tip and owning a 2000 S that had a 2.5L (1997) swapped into it before I bought it.
My advice.... Read Woody's (itsnotanova) post about a dozen more times and let it sink in. Don't take any action until after the holidays.
