So the 09 997.2S I purchased recently has the Sport PASM option which includes LSD. For some reason this car feels very strong when compared to my previous .2S ( which had standard PASM and no LSD) and others I have driven. It does not have a tune or exhaust mods, I'm thinking maybe the LSD has a lower gear ratio which accounts for the stronger acceleration. I don't think it's in my head, Tim Holt Sr who I bought the car from had the same impression. Anyone know if the LSD has different gearing than the standard differential?

There are car-to-car variations for identical models. Usually that’s dominated by service condition (filters, etc.). But there are also variations from engine to engine (manufacturing tolerances, etc.) off the manufacturing line. For example in the old days (because I don’t know if this is still true), a cylinder boring tool had a finite life. At the beginning it’s producing bores at one end of the tolerance range, and by the end of its life it’s at the other end of the range.

Over the years the manufacturing process have improved so as to tighten up the variations. But it’s possible all the stars aligned on the day your 2nd engine was made and it came out stronger than average (and perhaps the reverse for the 1st one). Just speculating...

There was an interesting example of engine variance in the August 2000 edition of Excellence Magazine. Alois Ruf (owner of RUF) commented on 3.4L 996 crate-engines from Porsche at that time (issue #95, p68):

• "We have tested dozens of 996 engines now and seen outputs between 285 and 300 horsepower."
• "We claim 310 hp for the Boxster 3400S, so if a new 911 engine out of its create doesn not make 300 hp to start with, we will find out why and rectify it"
• "If that means stripping it down and blueprinting it, then that is what we will do."

So they were seeing 292.5 hp ± 7.5 hp (~5% or 15 hp total) variation on the crate engines...

I’ve had two examples in my personal experience.

The first was when buying a used 944 S2 many years ago. I was lucky in that there were four MY1991 examples (with the bridge spoiler) for sale locally at the same time, all stock, and all roughly in the same mileage and condition. Three of them drove the same, but one clearly stood out as being stronger than the others (and it wasn’t a subtle difference). I bought it and owned it for many years. Never found anything that didn’t look stock (including the DME).

Another much more prosaic example was when buying a new VW Passat Wagon back in 2005. We test drove two identical examples on the same dealer lot back to back (only difference was color). By comparison, the first was a dullard and the second was sprightly. We bought the second one.

So I’m personally convinced that car-to-car variation for an identical model was a real thing back in the day.

Hence you should always test drive a car before buying.

But whether it’s a real thing now for cars made in 2018, I don’t really know...

Karl.

Thank you Karl, very informative and certainly explains my experience