Lugging - Fuel Economy, Hypermiling, EcoModding News and Forum

pete c · 03-01-2012, 09:49 AM

I have a question regarding lugging while P&Ging.

Most of my commute is on roads with speed limits in the 30-40 mph range.

When there is no traffic behind me, I will generally glide down to close to 30 mph, which is about my minimum 5th gear speed (V-6 ranger, 5 speed stick).

If I extend my glide a little to long or have some sort of uphill, I sometimes get into the lug zone a bit. I can stay in 5th, with very light throttle and accelerate very slowly, smoothly, or I can momentarily drop to 4th or sometimes 3rd, accelerate hard and be back into 5th fairly quickly.

Which is better?

Do I burn more fuel putting up with a few seconds of very light throttle to nurse it out of the lug zone or should I go to a lower gear where I can go to a more efficient 80% throttle.

I do not have a scan guage, unfortunately.

Does anyone have a BSFC graph for the vulcan 3.slow V-6?

Daox · 03-01-2012, 11:46 AM

I'd suggest downsifting anytime you're lugging. You don't have to keep the rpms THAT low.

MetroMPG · 03-01-2012, 12:08 PM

Also: get a scangauge! It'll pay for itself. (And you can always re-sell it later.)

Note there are less expensive options than the full SG 2, such as the ScanGauge E and the UltraGauge.

pete c · 03-01-2012, 01:03 PM

Quote:

Originally Posted by Daox

I'd suggest downsifting anytime you're lugging. You don't have to keep the rpms THAT low.

that's the thing. I'm at a point where I am not really lugging at low throttle inputs, but am if I step on it.

i am guessing that downshifting probably does make sense in this case, as fuel efficiency just above lugging, probably ain't anything to write home about.

i 'spose a little extra left leg exercise is good for me, anyway and doesn't really cause much extra wear.

PaleMelanesian · 03-01-2012, 01:25 PM

What rpm are we talking about? I like to run mine fairly low, pulsing from 1300 rpm on up. What's efficient is 80% LOAD, not throttle. At very low rpm, that load level comes with the throttle just above idle.

pete c · 03-01-2012, 02:48 PM

Not really sure what the revs are, as I have no tach. Interesting point about the difference between load and throttle position. I wasn't aware of it.

I 'spose I will modify my p&G technique a bit and incorporate 3rd/4th gear a bit.

cfg83 · 03-01-2012, 02:50 PM

Pete -

Quote:

Originally Posted by pete c

that's the thing. I'm at a point where I am not really lugging at low throttle inputs, but am if I step on it.

Happens to me all the time. I downshift if I need to accelerate quickly. If I need to increase my speed and I can take my time then I am super-gentle on the throttle until I get out of the "lug zone".

Quote:

i am guessing that downshifting probably does make sense in this case, as fuel efficiency just above lugging, probably ain't anything to write home about.

i 'spose a little extra left leg exercise is good for me, anyway and doesn't really cause much extra wear.

Me too.

CarloSW2

bestclimb · 03-01-2012, 03:12 PM

I think the art of driving efficiently has more to do with how you decelerate and what you do with your velocity once you have it than how you accelerate. Use a gear that allows moderate acceleration and a throttle position that is just backed off of where adding more does not increase acceleration rate. That is about as good as you can do without instrumentation.