willisit

I'm sure your "US" manuals have this "lug" term in it, but I don't think the UK one's would (I have no idea, mine is a German car). It's certainly not a term widely used here in the UK (I've never heard it)... but it certainly makes sense.

I'd say something like "taxing" or "straining" etc...

I cold change at between 3,500 to 4,200RPM - the power is only just coming in at 4,000RPM

Caveman

I would agree that 3,500rpm is a good limit to set yourself when driving a cold engine though the overriding concern is not to load the engine too much. Once it's warm I love giving it a decent run though on the motorways you can comfortably cruise at about 3,000rpm in 6th (maybe a bit less officer!) and in town my 911s have always been happy trundling around at 2,000ish revs (though obviously you need to downshift if you want to accelerate hard.

Cheers,

David

Speedraser

Both lugging and unneccessarily high revs are bad for an engine. Below is a slightly modified copy of my post from another thread:

I simply do not believe that cruising on the highway at 80 in 4th does anything good for the engine (note to CP: I don't know what your RUF revs at 80 in 4th). Surely the engine is not running too rich or inefficiently at 3000 revs, which is 82-83 in my stock 993 in 6th. Pete (Blackcat), I seriously doubt that 2800-2900 revs in 6th had anything to do with causing your CEL. These are modern, electronically-controlled engines, not '60s or early '70s muscle car engines or early 911S engines that really need to be revved very hard to avoid plug fouling or other similar problems. If you're cruising in 4th at 80, each engine component is going up, down or around many more times than it would be in 6th -- this HAS to cause more wear to all of those parts. For example, valves are moving up and down in their guides that many more times at 80 in 4th vs. 6th. Constant higher revs almost certainly increases oil temps as well. None of this is good.

My car sees redline fairly often, but that's when I'm on a track or just having fun. Lugging an engine should always be avoided, but I see no reason to drive through town at 4000 rpm, nor cruise on the highway at those revs (unless its 4000 in 6th ). If I'm in a situation where I might need or want more acceleration, I simply downshift. Also, I shift at 3000 - 3200 when the engine is cold. No, there isn't much power yet, but when the engine is cold you shouldn't be asking it to make much power -- heavy load while cold will kill an engine. And revving higher than needed just wears everything out faster.

CP

Todd,

My RUF at 80 MPH runs 4,000 RPM in 4th, and 2,600 RPM in 6th.

You made an excellent point that the higher the RPM, the more revolutions the engine endures. I'll cruise in the highest gear from now on.

Thanks.

CP

aap

ONe of the unique traits of these cars is the "growl" you hear when cruising at 4K RPM. Unmistakable! Don't LUg!