Questions Of My Way Into Work ...

[Drstressor]

I don't interpret the data in the charts the same way you do, Widman. It looks like both ring and bearing wear increase with rpm or load. It's just that the absolute rate of wear in much higher for the ring material at any speed or load. The most instructive information in the graphs is how a CHANGE in rpm or load causes a transient increase in wear. That's why hard acceleration increase engine wear. Hard acceloration and/or high rpm would be expected to have an even greater effect in a cold engine where it would take longer for the oil film to recover under conditions of low flow.

 

[Ken2]

quote:

---

Originally posted by toyvwbenz:
I think that load is also a factor in engine wear, especially when the engine is cold. Therefore, running at 55 in forth gear reduces the amount of load on the engine/transmission, which reduces wear. Whether or not this load/wear reduction is enough to offset the rpm/wear?????? My incilination is yes. JMO

---

For the same power level, load is less at higher rpms. A pretty good analogy is what happens when I ride a bicycle. At the same bike speed, the load on my creaky knees is easier in a lower gear/higher pedal rpms than it is in a higher gear/slower pedal rpms. Your engine and transmission work about the same way--equal hp, higher rpm = lighter load.


Ken

 

[Pablo]

Keep it simple: DRive in 4th until the engine just starts to warm. SWitch to 5th. Complete drive to work.

 

[TallPaul]

quote:

---

Originally posted by Patman:

quote:

---

Originally posted by TallPaul:
If I were rich I would keep my baby in a heated garage

---

And with both a block heater and oil pan heater too!

---

Y'a know, the pan and block heater would be a good idea in the summer too. 80 F ambient summer temp is not exactly engine operating temp. I wonder if I can tap the electric from the street light post down where I park for work? Shoe Goo in the rust holes in the body (really, I do), but only the best for the engine!

[ December 16, 2003, 01:28 PM: Message edited by: TallPaul ]

 

[VeeDubb]

Ted,
Interesting questions. Here's my attempt at answering:

1. Depends on the engine. We need to know piston speed to answer the question. The best method is determined by optimizing some function on the (RPM, warm up time, piston speed) space.

2. It can be determined analytically. But a controlled study would be nice for verification.

3. It depends heavily on engine design because piston speed will vary.

4. Yes. It is independent of temperature.

How many did I get, if any?