Hello cold start rev limiter
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Joined: Feb 2004
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From: Dry Branch
Unless it's pretty hot the tires don't warm up fully in a mile and a half of (normal) street or highway driving. Take it easy until everything is up to temp.
LOL, the airbag should deploy when you rev to 6k with a cold motor.
LOL, the airbag should deploy when you rev to 6k with a cold motor.
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From: Bonita Springs, FL
Originally Posted by mikeyr,Apr 7 2007, 09:41 PM
What are you doing trying to rev that motor when its cold ?
You wont catch my S anywhere near 4,000RPM when the motor is cold. After the water warms up to temp, my motor might see 5,000 RPM every now and then. But forget anything above that for at least 10 minutes of the motor running, its not water temp you are concerned about, its OIL temp ! and it takes a long time to warm up the oil.
My other car has a oil temp gauge and it takes about 1 to 1.5 miles to get the water up to temp, it takes 10+ miles to get the oil up to temp and I won't rev that car up to its 8,500 Red line until the oil is good and hot. Same for the S, NEVER REV UNTIL THE OIL IS HOT !
You wont catch my S anywhere near 4,000RPM when the motor is cold. After the water warms up to temp, my motor might see 5,000 RPM every now and then. But forget anything above that for at least 10 minutes of the motor running, its not water temp you are concerned about, its OIL temp ! and it takes a long time to warm up the oil.
My other car has a oil temp gauge and it takes about 1 to 1.5 miles to get the water up to temp, it takes 10+ miles to get the oil up to temp and I won't rev that car up to its 8,500 Red line until the oil is good and hot. Same for the S, NEVER REV UNTIL THE OIL IS HOT !
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From: Dry Branch
Originally Posted by maxsales,Apr 8 2007, 10:09 AM
This is interesting to me. Oil is a lubricant and as such it's friction reducing properties should be as good or better cold, higher viscosity, then warm. I have always been advised that you are looking for oil circulation on start-up, and once that was achieved everything was a go. further warm up was then mainly to wanting for operating tolerances to reach the normal range.
I've never actually seen it happen, but apparently some cars can produce enough oil pressure with thick/cold oil at high revs to burst some oil filters.
Once up to temperature the oil flows at the proper rate and pressure to both lubricate and cool the engine. This is not the case when the oil is cold (or when it is over heated).
In addition to the oil issues, engines use many different metals that have different expansion rates, so most engines are dimensionally unstable until they stabalize at operating temp.
With the F20C, once you have three bars of water temp, the engine, oil and all, is warned up enough to run hard. The tires on the other hand, might still need some additional heat to work well.
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i thought liquids were more viscous at lower temperatures because there is less kinetic energy in the molecules... and visa versa, high temperature = low viscosity... maybe i just failed middle school chemistry and no one told me? 
