991.2 Tire Pressure, Engine Run-in Period, Revving Engine
#1
Instructor
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I had a call with Porsche product specialist based in PCNA HQ in Atlanta GA and learnt the following,
a) Tire Pressure - the pressure suggested in the door jamb is for your vehicle, as it is configured, with full pay load; that is 4 passengers, baggage and all. None of us are likely to ride with this kind of pay load. Like most 911 drivers, if you drive by yourself, with an occasional passenger, and nothing in the frunk or elsewhere that adds to the payload, go by what is suggested in the manual for Part Load. You can choose a lower tire pressure, 'Comfort Pressure', for a smoother comfortable ride. However, your top speed is limited to 165 mph, increased rolling resistance accelerates tire wear and consumes more fuel
b) Run-in period - Porsche recommends run-in period for a country depending on the fuel, with typical additives, that is being sold locally it seems. US being the vast country it is, has all kinds of terrain; high altitude, harsh cold weather, hot desert and everything in-between. For this reason, fuel sold in the US is mixed more additives (than a European country for example), which is not a bad thing, he added. Hence the 2,000 mile run-in period for US owners
c) Revving Engine - Revving the engine before it has reached its operating temperature can harm the engine (more than revving it past 4,0000 RPM once-in-a-while during run-in period I suppose). Operating temperature is when the engine oil temperature (NOT coolant temperature) has reached 150 deg F. It takes a good 5 mile drive to get to that temperature
Hope above is informative and useful.
a) Tire Pressure - the pressure suggested in the door jamb is for your vehicle, as it is configured, with full pay load; that is 4 passengers, baggage and all. None of us are likely to ride with this kind of pay load. Like most 911 drivers, if you drive by yourself, with an occasional passenger, and nothing in the frunk or elsewhere that adds to the payload, go by what is suggested in the manual for Part Load. You can choose a lower tire pressure, 'Comfort Pressure', for a smoother comfortable ride. However, your top speed is limited to 165 mph, increased rolling resistance accelerates tire wear and consumes more fuel
b) Run-in period - Porsche recommends run-in period for a country depending on the fuel, with typical additives, that is being sold locally it seems. US being the vast country it is, has all kinds of terrain; high altitude, harsh cold weather, hot desert and everything in-between. For this reason, fuel sold in the US is mixed more additives (than a European country for example), which is not a bad thing, he added. Hence the 2,000 mile run-in period for US owners
c) Revving Engine - Revving the engine before it has reached its operating temperature can harm the engine (more than revving it past 4,0000 RPM once-in-a-while during run-in period I suppose). Operating temperature is when the engine oil temperature (NOT coolant temperature) has reached 150 deg F. It takes a good 5 mile drive to get to that temperature
Hope above is informative and useful.
#4
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True dat. It has nothing to do with U.S. fuel. Porsche's top engineers have already stated in interviews that the issue is that the motor can be damaged by very high engine heat during run in such as that caused by extended high rpms, i.e., like a car is subjected to at the track. Porsche has this limit solely to discourage taking the car straight to the track, or driving like that on the street. A properly warmed up engine can be driven hard in short bursts with no issue whatsoever.