When am I lugging?

[humfrz]

If you think you're lugging the engine ....... you probably are ......


humfrz

[Gords_zenith]

it depends on the displacement of the engine to determine what's lugging. For example my ford ranger 4.0 SOHC is happy to putter at 1K rpm, but the BRZ is a lot happier to be no less than 1600-1800rpm. This is the rpm that will allow you to accelerate, albeit not aggressively

My two cents.

[Tcoat]

Originally Posted by Gords_zenith

it depends on the displacement of the engine to determine what's lugging. For example my ford ranger 4.0 SOHC is happy to putter at 1K rpm, but the BRZ is a lot happier to be no less than 1600-1800rpm. This is the rpm that will allow you to accelerate, albeit not aggressively

My two cents.

Displacement has little to do with it. It is more in the gearing. Yes a larger displacement may be able to go a bit lower since it does not make power through revs but it still needs that minimum based on gear.

[dostoyevsky]

So If im going say, 5mph should I put it into 1st or just accelerating from 2nd is okay? Like I always accelerate from say 5-7mph and the engine does vibrate but quickly recovers.

[Blue Bird]

Originally Posted by dostoyevsky

So If im going say, 5mph should I put it into 1st or just accelerating from 2nd is okay? Like I always accelerate from say 5-7mph and the engine does vibrate but quickly recovers.

5mph in 2nd gear is like under 1k rpm no? I downshift back to 1st gear when I'm going under 10mph

[Da Brz]

Shoot, I keep my rpms low all the time. I routinely beat every EPA estimate in the book that way.

As for lugging... well just listen to the engine. It'll let you know what it doesn't like. The car will start hopping forward and falling on its face.

You can run a low rpm just cruising, just remember to gear down before accelerating. High 30s seems to be the lower limit for sixth in mine.

I've noticed the BRZ clatteres like a diesel when I'm creeping through parking lots in second. I think that's just the direct injection kicking in though.

Really though, don't think about it too much. It'll let you know when you're doing it wrong, by hook or by crook. If the engine doesn't, the clutch will, lol. I think everyone remembers that smell from when they were young.

[alan.chalkley]

A lot has to do with either rolling downhill or climbing uphill.
This is with driver only in car.
Rolling down at 60kph , 6th is fine.
On a level road 70kph minimum for 6th.
The slightest hill climb will need downshift.
With a passenger and a load of luggage , add 10kph for 6th.
Try driving with the backseat down and you can hear if there is any lugging.

[radroach]

@Da Brz

No, that clattering is your flywheel rattling against your pressure plate. Downshift to 1st before that happens. It's not hard to downshift to 1st under 10 mph. I also noticed you've made posts about your car knocking when coming to a stop. Perhaps you are keeping your rpms too low. I think the lowest rpms you should cruise at safely should be about 2500 rpm. There's no reason to almost lug this engine just for muh mpg's when it runs efficiently enough when driven right.

[humfrz]

Originally Posted by Tcoat

Displacement has little to do with it. It is more in the gearing. Yes a larger displacement may be able to go a bit lower since it does not make power through revs but it still needs that minimum based on gear.

True.

Back-on-the-farm we had a 1941 Ford 1.5 ton truck with a flathead V-8.

When put into the "granny gear", even with a half load of hay, I could let the clutch out, in a rough hay field, and not touch the gas pedal and it would just jug right along.

Why did I do that ....?? Because, I was so small, I had to open the door to see out ...... and I couldn't reach the gas pedal while leaning out to see where the next bale of hay was.

(ohhhh......I think I've told that story before ...... )


humfrz

[humfrz]

Originally Posted by Da Brz

Shoot, I keep my rpms low all the time. I routinely beat every EPA estimate in the book that way.

.

Oh, I'm not so sure your engine likes that. The engine in my car seems to like being at 3,000 rpms or above .......once it gets warmed up.




humfrz

[humfrz]

Originally Posted by radroach

@Da Brz

No, that clattering is your flywheel rattling against your pressure plate. Downshift to 1st before that happens. It's not hard to downshift to 1st under 10 mph. I also noticed you've made posts about your car knocking when coming to a stop. Perhaps you are keeping your rpms too low. I think the lowest rpms you should cruise at safely should be about 2500 rpm. There's no reason to almost lug this engine just for muh mpg's when it runs efficiently enough when driven right.

Actually ...... since the flywheel is bolted to the crankshaft and the pressure plated is bolted to the flywheel ....... what is chattering is the clutch disk rattling against the pressure plate and/or the flywheel .....

(I'm practicing on being like @Tcoat ....... ........ now THAT should get a rise out of SOMEONE ......)


humfrz

[ls1ac]

Most clutch plates have springs to help keep the system from bucking, but at that low an RPM they just can not handle the changes in the engine speed. (They also help with mismatched shifts).

[ls1ac]

Actually the springs can exacerbate the problem at that low a speed

[Ultramaroon]

^^^truth^^^

OP, when you're operating the car with the engine between idle and 2K, the trick is to not give it any more gas than it would take to gradually rev up the engine in neutral.

While standing still in neutral with the engine at normal idle, gradually step on the gas. Raise it to 1000 RPM and hold it. That's as much gas you should give it when you accelerate from a crawl at idle.

Now gradually go from 1000 to 2000 RPM. ...

Practice that and you'll get how to not lug the engine. If you ever make it chug below 2000 RPM, you're doing it wrong.