Thoughts on mileage of replacement engine?
 

Hello.
I've found a replacement engine for my blown 2.5. It has done 151K kilometres or around 100K miles. It is affordable at around $2000k and is in the country. The car was running at the time of impact.

Would you consider this past the rebuild date for track use (trackdays)? Or would you just run it till it blows?

My other option is to have my engine sleeved to 2.9l and completely overhauled for the price of around 6-7 engines like this one.

The third option is to get a more expensive , lower mileage used engine from abroad, import it and pray it is OK:

Thoughts?

The mileage on the 2k engine is less a worry than how it was maintained. Does it come with any history? IMS changed? This is a good opportunity to replace the IMS and tensioners and rails while the engine is out.
Then you can tear down the old engine and think about sleeving etc. The rebuild information is out there if you decide to give it a go. You might surprise yourself!

Tom documented his spec racer Boxster on here for years: https://986forum.com/forums/boxster-racing-forum/46070-spec-boxster-build.html
He replaced the engine a few times and considered the engine to be a consumable part like brake pads and tires (though hopefully with a longer interval).

I recommend checking it for obvious flaws first. If it is good, do the basic engine out maintenance before installing it. Depending on budget and expectation of how long the engine will survive with heavy track use, I probably wouldn't replace the IMS bearing or do an in depth rebuild. If you want a 'bullet proof' engine it's going to cost a lot of money and still may fail unexpectedly.

I have a $2,000 engine in my rallycross car now. I replaced RMS, coils, spark plugs, spark plug tubes, AOS, water pump, and engine mount. Probably should have done the cam chain pads too while I had it out, but didn't take the time. I drive the car hard and don't worry. If I kill it, I'll spend another $2,500 for that consumable item.

*If affordable replacement engines are hard to come by where you are at, then that may be a different story. I can still buy faulty, but complete 986 Boxsters for under $3,000.

Note: The this post is about an engine for a track/race car. My views about car primarily for street use are different.

What Tony said!