I'd always heard that it's not good to "lug" an engine. My wife is guilty of shifting way too early in her Honda--and I'm always on her to wind it out a bit. With a GP on the way, I want to make sure we are doing the best for the engine--what RPM range is best to shift at in daily driving? Is it best to wind it up to near redline (after it's broken in)? Are their negative effects of lugging the engine? I'll be driving the GP most of the time, but I anticipate that with the noise it will make, the misses will be wanting to shift at 2000RPM!
Thanks

 

Tell her to learn to take it up 1k, I shift a 3k went I need mpg (like this afternoon when I filled the tank plus 1/2 gallon of fuel lines. In daily driving with traffic and the like, 4k is good for a short quick not get me in too much trouble, at the track I'll shift around 5.5k as thats about where the torque curve peaks out. If I want to make some noise or get a 0-60 with one shift I can run it up to redline without damage but thats where your risk is greatest of screwing things up if you say hit 4th instead of sixth or 3rd instead of 5th as the rev lmiter will stop you from doing damage in gear it's not fast enough to stop you when shifting.

 

I've always been told/taught that it's not good to lug a cold engine. It's not as bad if it's operating temp, but still not good practice.
BTW, I shift around 3-3500rpm when just driving normally. I'll hold it out to 4-5000rpm when getting on the highway ramps. The SC whine is very addicting.

 

Yes it's bad, but since 2000rpm shifts would keep rpm above 1200 in the next gear, that's not lugging and will be just fine. However I've found fuel economy to be no better than if shifting at 3000.

Lugging=shaking and you'd know it if it happens.

 

@ what RPM do you find lugging to begin? I feel some lesser degree of lugging as soon as 2100-1700 RPM, so I try to stay above 2300-2400.

 

Like when you're up a hill with speed bumps?

 

The last moments before stalling the car is a similar sensation, as luggin is the warning signal to a stall at low speeds much the same buffeting is warning to a stall to aircraft, I'm good at hearing it and feeling it in the clutch pedal.

 

I shift at 3000-3500 rpm usually, unless I need to be more spirited for freeway passing, then it's more like 4500+ rpm. 2500 rpm is probably okay, but sure isn't as much fun!

 

Things do not start to get rough here until heavily loaded at 1000rpm, but I have a 19%, GIAC and injectors.

I drove for an entire tankful shifting furiously to keep the rpms between 1700 and 1200, but since fuel economy did not improve, shifting at a more leisurely 3000 is less work and more fun.

Before the 19%, there was insufficient torque to comfortably drive at such low rpm. I'd imagine a torqueless wonder Honda would be intolerable to drive that way. They're rev-happy.

One of the hallmarks of a V-12 is the ability to load the engine heavily at idle speed without any lugging. 4-cylinders are not nearly so tractable.

 

i don't pay much attention to the tach as i listen more than anything
else, but for starting off from a stand still i always catch the tach with
my peripheral vision being in the horizontal (9 o clock) position before
gently engaging first. for newbs, that's about a full 3 second slip
engagement for your reference. don't engage too soon as the motor
will lug, and dont engage too slow as the clutch will heat up.

from there, i let all my MT cars spool to at least 3000rpm for 1st
and 2nd gears, usually close to 4k on my 03 MCS for 1st and 3.5k for 2nd.
cruising rpm 2500-2800 range on the MCS.

 

What!? Cruising at 2500-2800 doesn't cause lugging, Ken? Do you ever get up to highway speed?

 

Up here in IL the max limit in the state is 65 (rural interstate) and all the Chicago Suburban highways in IL are 55, 2700 in 6th is plenty

 

Ah...I am not familiar with IL's roads and driving conditions. Thanks for the info!

(Actually, I was really only teasing Ken...)

 

like i said, ive never gone faster than 55mph.

 

Well if you're calling our driving conditions into question I'm not sure why some of the speed limits are so high as most roads are ethier under a foot of snow or under severe construction so there is ALWAYS traffic:impatient :impatient


And I knew you were teasing Ken.

 

let's stop now before we need to lock the thread!

 

Yes, disscuion of excessive speeds, does include excessivly slow driving.

 

yes, even at 55mph, compared to how you drive it may be so.

 

Could I get my first strike if I discussed how I went 15 mph on that section of highway that has a 40 mph minimum speed?

 

Maybe!

And for you Chicagoans, Texas has upped their highway speed limit to 80 mph, so 55 WOULD get you a ticket!

My travels have me experiencing a variety of posted highway speeds.

 

Lugging an engine is bad because you can get high cylinder pressures when you have low oil pressure. When you have low oil pressure, your oil film in the journal bearings won't stand up to the forces exerted by the pistons and you can score the bearings via metal-to-metal contact.


I stole that off another forum from a thread about proper break-ins for an engine. I doubt I'll get sued for copyright infringment though.

 

I usually shift between 3500 and 4000. I guess that's a bit higher than most have mentioned. I've never needed to hit 4500+ or shift below 3000. It just seems that's what works for me and my MINI!

Oh and stop typing in grey you're straining my eyes!!

 

so that's why MINITOR moved to Texas recently!

 

My rule of thumb for those new to manual trannys.

Upshift at 4-5000 rpm.
Downshift at 2000 rpm. (except for going into 1st gear)

Your wife is upshifting when she ought to be downshifting (or staying right in the gear she's already in).

 

I ususally shift around 3000rpm when driving regularly, I never let it go below 2000 though, for manual transmission vehicles it's usually not a good idea to cruise under 2k.