High miles and leak down numbers

[Reiver]

I just got Wayne's book on rebuilding a flat 6 911. Really a nice booklet.
So I'm looking at the "When to rebuild" section at the leak down numbers and oil consumption.
He says a newly rebuilt flat 6 will have from 3 to 5 psi leakdown and under 10 for a 'driven/car with miles' in good to go shape.
I don't get it, so am I just lucky or do other very high mileage cars retain good comp/lk down if taken care of.
I've had 2 leak downs done by 2 diff shops in Phoenix....Jacksons and Stuttgart SW...both well respected indy's.
The tests were done 11k miles apart...at PPI and recently and both showed similar numbers with an avg of 4-8 psi.
This was at 215k miles and 226k miles.
Did I win the Porsche lottery or what?
The 30 year old SC runs like a top, I run it correctly (warm up etc) but with gusto and it just acts like it's freakin 'new'.
I'm not woofing as they say in the Army, just amazed.
I've seen the high mileage threads but wondered how many unopend high mile cars had their LD numbers and what they might be.
Anyone have some LD stats that are similar?

[Targalid]

If it ain't broke don't fix it.

[moneymanager]

I ran a 2.4 with leak down numbers in the 10-20% range for five years before rebuilding. THe car ran strongly and used almost no oil. Take these numbers with a grain of salt and, in your case, enjoy your next 100k miles.

[john walker's workshop]

oil consumption is a good indicator of when it's time. a qt in 1000 is normal. a qt in 300 is time.

[OsoMoore]

My SC had a rebuild at 200K. During the PPI at 238K miles, here were my numbers:
Engine cold, in firing order:
#1) 2%.. #6) 2%.. #2) 5%.. #4) 5%.. #3) 6%.. #5) 4%

Its now at 247K.
It uses about a liter of oil every 500 miles. SCs are the best!

[nettles503]

Those #s are impressive.

When I bought my '86 3.2 Carrera last June, here are the compression and LD numbers from the PPI I had done on it:

Cyl. 1: 160/10%
2: 150/8
3: 155/10
4: 155/10
5: 155/8
6: 150/8

I've since put 6,000 miles on the car. My oil consumption seems to be about a 1/2 to 3/4 qt. over 3,000 miles (not really worth topping it off), so I'm pleased with that.

EDIT: I neglected to add that the engine had 112K miles on it when I purchased it.

[Reiver]

Good info and the LD numbers for high miles is/are phenominal really. I'm getting 600 to 650 mp qt and have been for the last 11k miles (a year since purchase)....'83 SC btw.
The oil pressure is excellent...yesterday 75 degrees, 90 mile trip at 3k rpm almost 3.8 bars and 1 bar at idle.
I'll do another 50k prior to another check up.
These cars really are the heat.