So I got a question. let's say you're on a road going 35-50 mph, no traffic lights, no real traffic but you can't go more than 50 mph. What gear should you be in? I am wondering if this is too slow to be in sixth gear... and even if being in sxith gear is the most economical. And is it bad to be in sixth gear at non-highway speeds?

Q

 

I put it in 6th gear around those speeds. Doesnt really hurt anything, atleast that i know of. Saves you gas just like you were saying. But sometimes if its even moderate traffic its a pain because of all the shifting. Its all on what gear you want to cruise in really.

 

First, I'd be interested in hearing further discussion on this topic - post more, feed me !

One "general truth" that I know (read, please correct me if I'm off base):
Lower gears = higher rpms at a given speed = negative effect on fuel economy. That being said...

Stop and Go traffic:
On first reading DrQ's post, 6th gear on urban thoroughfares (35-45mph speed limits) seemed wrong. Going by "feel" (I could be wrong - again please set me right) my MCS's 4th gear was very comfy at those speeds. Heck, I can get to 40+ mph in 3RD, with quickness, without exceeding the 4500rpm maximum (per break-in guidelines).

I have only been motorin' for a week (<500 miles, but I'm workin' on it ). I didn't do this consciously, but I find myself wanting to DOWNshift if the tach is close to 2000, and UPshift when I'm over 3500 for more than a moment... It just "feels" acceptable. I wouldn't use 4th gear at 25mph.

At my first fill-up since delivery, having driven about 275 miles, I calculated (no On Board Computer here) 23.5 mpg... Oh well, maybe she wasn't completely full when we left the dealer's. It was 90% stop & go type driving, too.

Expressway:
On the freeway, I'm typically over 50 before shifting to 5th, and even faster than that before shifting to 6th. Again, the "comfort zone" for RPMs is what I'm going by. Maybe the motor is perfectly content at low RPMs/higher gears, and the "problem" is just the proverbial "loose nut behind the wheel".

MINI is obviously a beast of a different color, compared to the older (circa 1967-68) Volkswagens in the (brrr cold) confines of which I became intimately acquainted with the manual transmission, some 25 years ago...

In THOSE cars "lugging the engine" was something you didn't want to do.

Maybe the dramatically less H.P. (in the old VeeWees) has something to do with the different driving styles (if they even ARE different). I came by this knowledge from the VW mechanics in my family, of the shady-tree variety, who routinely coaxed 200,000+ miles from those old air cooled engines, so I was happy to drive 'em "their way" cuz it seemed to work. In our family, when a VW died, it was invariably from the dreaded rust cancer, rather than a result of neglecting or mistreating the engines. Whoops, I digressed...

RPMS generally between about 2700 and 4000, and shifting accordingly, is what seems right to me (during break in anyhow - I can not WAIT to have FUN once broken in). If I'm "educating" my ECU in a less than optimum way, someone please hurry up and tell me.

Thanks in advance for Your Thoughts,
Tatt

 

In general, I try to keep the revs above 2k unless the car is idling.

 

Kewwwl, an assenting opinion from a veteran poster, I appreciate the quick feedback. One quick question though, I wonder what your tach was showing when you managed to lift the rear wheel in your pic!?!? I can almost feel that weight transfer, here in Chicago!

Gratefully,
Tatt

 

I try and keep the revs above 2.5k which means at 70 I can get into 6th gear. Anything slower it doesn't like it. Of course I'm one that like to keep the RPM at around 4/5k with a min of 3k.

Earl

 

DrQuinn - generally I drive by the tach ... and keep it around 3k. Which would mean that you would be in 4th gear (3rd = 40mph, 4th = 50mph, 5th = 60mph and 6th = 70mph). At this rpm if I need to adjust my speed I can do it with the throttle, not the brake or transmission.

 

Your question boils down to "when is it proper to shift up or to shift down at a given rpm?"

Shift up when you reach about 3000 to 4500 rpm. For best fuel economy you can choose to shift up earlier (at a lower rpm) but for best performance then shift later even at 5000-6000+ rpm.

Shift down when you reach about 2000 rpm, any less rpm and you are going too slow to stay in that gear (lugging).

Generally when I am not on the highway I do not use 6th gear. Up to about 50 mph I'd be in 3rd or 4th and maybe 5th when over 50.

 

Keep it between 3 and 7 thousand rpm while driving. Stepping on the gas at 1500 rpms is not going to help your emissions or mpg...you don't have a diesel

 

I don't know about Mini's in particular (only have 400 miles on mine) but I learned in the past that as long as you can accelerate smoothly and without hesitation when you hit the throttle you are not in too high a gear.

 

I would be in top of 3rd or 4th between 35-50mph.

 

I seem to be letting the revs drop lower in my MCS than I did in my Jetta 1.8T.

Being a lazy shifter, if I know I'm going to go a steady 45 or 50, I'll shift from 3rd directly to 6th once I get up to speed.

My car lurches a little when the revs drop below 2000 (a reminder to downshift, I guess?). Once it has done that, my car is happy to go as low as maybe 1200 if I don't need it to accelerate.

 

So the consensus is to not dip below 2000 rpms...? Is it because it can cause wear on the clutch or engine or just because there's no power at that speed if you did try to get up to speed?

THe reason I ask is because I live in downtown Tampa and there's a lot of the 35-50 mph cruising around, and I'm not sure which gear is best for A) Gas economy and B) Less strain on the engine/clutch.

Q

 

The higher the gear, the better your fuel economy and the less work the engine has to do. You can drive under 2000 rpm, you just won't have any get-up-and-go when you try to accelerate.

Your clutch is only affected when you shift. Once you're in gear, your clutch doesn't care if you're in 1st, 6th or anywhere in between.

 

The answer will also depend on your engine power ... obviously you have an MCS (you mention 6th gear).
I will generally go into 5th at 40-50 for round town driving; I find my JCW equipped GBMINI accepts staying in 5th right down to about 25! So long as I don't need sudden acceleration (which is unlikely in town), I can be very lazy and leave it in 5th ... before the JCW, I could not have done that.

The engine will "tell you" if it does not like what you ask of it; GBMINI will complain if asked to drive below about 1300 rpms; but below about 1800 there is not much torque left to drive with.

 

In my experience, gas mileage is not necessarily related to RPM; it is determined by RPM and torque load, and therefore more directly related to throttle position. Unless I'm mistaken, if you floor the pedal in 6th at 50 mph to accelerate around a car, you are then running the engine full rich. The same exercise in 3rd or 4th gear requires you to open the throttle less far, so less gas is used in overtaking.

Now, regarding cruising gas mileage, my '04 S's computer, if put in mpg mode, shows that during acceleration in any gear (particularly first and second), the mpg reading goes down until some point (it varies a little per gear), when the mpg begins to climb higher. It's like 2k in 2nd if I remember right. That point is always near the torque plateau, hence my suspicion that realized mpg is partially due to torque load. Anyways, I always try to keep the revs at least above 2k when cruising, since my baby seems to give best gas mileage there (I've undergone significant mpg testing these past 6k miles ). What do you guys think?

 

I tend to cruise at about 3.2k in 6th.

 

6th Gear I cruise at about 3k seems to get me pretty good mpg.

 

Although it is true you can run the engine below 2k without putting much load on it (flooring it at 1500 rpm is a very unhappy experience for the engine to endure), the problem you run into is this. Say you are cruising at 1500, then a truck suddenly merges in from your right. If you were in a lower gear, at a higher rpm, you'd be in a position to just floor the accelerator and get away from that bad situation. If your revs are too low and your gear too high, you will lose valuable time by having to think about the situation and downshift.

 

I agree. crusing at 2k rpm or below does not = better gas milage.
I cruise 2.5k to 3k rpm with best milage on this car.

 

i second that...

35-50mph, most likely 4th or 5th.... anything over 60 i use 6th, otherwise i keep it out of 6th

 

My OBC disagrees with you. On flat level straight ground (which there's plenty of here in the valley of the sun) at a constant 30 MPH, I've tried different gears. I reset the OBC in between each shift and run for at least a 1/2 mile (about a minute's time). I've found that I can get in the high 50 MPG area with my modded '03 MCS in 5th gear (yes, much below 2k RPMs), while in 4th, it's lower, and in 3rd, it's lower yet, and in 2nd, it's even lower still, and in first gear, it's at it's lowest.

In 5th at 30MPH, it takes a light touch on the throttle to maintain speed with windgusts, slight gradient changes, etc. No, I would never ever try to accellerate heavily with the engine revving so low in such a high gear! If I want to go fast, I'll just downshift and punch it. Takes less than a second to do so.

 

I agree that this is true, but the moment in a higher gear when you make any throttle movement, you will notice that the mpg drops terrifically, since the engine needs more gas to 'work harder' and go any given amount faster. In fact, in high gears it can get to a point where you can press the accelerator quite a bit and still gain no speed, but still burn lots of gas in the process.

If, instead, you cruise in a lower gear and do that same speed increase (I find that slight increases are constantly happening while cruising), 1) the increase happens faster and 2) you need less throttle. Both make the procedure more fuel efficient (think of effeciency as gas burned per unit time).

To actually achieve the high OBC numbers in the long run on a road, you must not accelerate at all and you must maintain a very steady foot, because pressing the gas even just a little uses more gas, but may not get you anywhere in a high gear. My experience is you will achieve only very slightly more (but maybe even less ) fuel economy.

Anyone else have an opinion?

 

>In 5th at 30MPH, it takes a light touch on the throttle to maintain speed >Anyone else have an opinion?

yeh, who the hell drives 30mph in 5th in real world conditions?
hehehe. jk Do wat you need to do to maintain speed. I
recommend 2.5k to 3k rpm. :smile:

 

I think it greatly depends on what mods you have on the car - more specifically, do you have a pulley. Without a pulley, I wouldn't drive much below 3k RPMs b/c if you need to accelerate, it's a real strain on the engine b/c there's no torque there. With a pulley, you could drive around 2k RPMs very easily. Heck I practically came to a stop in third gear the other day and had no problem staying in gear and accelerating. But my MINI is full of torque.