Delivery Driver's Problems ('96 Civic CX ... seeking advice)

[digital rules]

Originally Posted by 96CX

As far as shifting early, I generally hit 2nd as soon as possible, 3rd @ 20-25, 4th @ 30-35, 5th @ ~45.

Sounds a little late for best efficiency.Not sure, how low your car is geared, but I generally shift between 1500-2200 RPM. RPM's kill MPG's.

3rd-15-20 MPH
4th-25-30 MPH
5th-35-40 MPH

In heavy stop & go traffic, I tend to go lower to avoid constantly shifting. If only very slow acceleration is needed I will go down to 1000 RPM's.

[96CX]

I don't have a tach...so I generally shift based on sound/speedometer, whilst keeping in mind the factory recommended lowest shift points (which, for mine, are 4th @ 33, 5th @ 48). I'll sometimes cruise downhill in 4th at 25mph (when I can do so with only minimal load), or go 20mph in 3rd (in the same conditions).

35mph in 5th *feels* like lugging to me. But then, I'm not sure what the actual definition of "lugging" is, exactly. Is it lugging the engine to drive up a hill in so high of a gear at such a low speed that the engine can't maintain speed (such as uphill at 25 mph in 3rd)? Or is that something else? Is it lugging if the engine speed drops below idle at that speed in that gear? Or is it only lugging when the vehicle lurches with each cylinder firing?

[MetroMPG]

You sure know when you're lugging an 3-cylinder! You definitely get an engine note & vibration that isn't nice (as well as not being able to increase or maintain engine RPM when needed).

I'd say the factory shift recommendations aren't in "hypermiling" territory.

I haven't met a 5-speed that won't cruise (on the level) in top gear at 25-30 mph. It probably won't climb or accelerate from that speed without lugging, though -- that's what downshifting is for.

[user removed]

Lugging an engine (in my opinion) is when you press the throttle further you get no change in acceleration. That applies if you need to accelerate, just maintaining a speed you can go very low in RPM, but need to downshift if you want to increase your speed.

My VX would max out at 120 MPH in 3rd gear (theoretically) but would also pull away in 5th gear at 30 MPH (1000 RPM).

regards
Mech

[96CX]

To be fair to the Honda Motor Corp.... they have two sets of recommended shift points-- one set for "normal driving" (rather high, imo), and one for "cruising" (much more reasonable, and on the low side); I quoted the "cruising" shift points.

Hm. Is lugging actually harmful to the engine, or does it just result in poor performance-- no acceleration and a terrible sound/feel at the time? I really don't want to break my car by experimenting with shift points...

In other news, I just filled up...36.6 mpg.

[MetroMPG]

Even Honda's "cruising" shift points aren't really ideal for maximum fuel economy.

Prescribed shift points are a big reason why it's so much easier to beat the EPA rating with a manual than an automatic.

You definitely won't hurt the engine by upshifting to the highest possible gear while cruising under light load. You're not going to break the car if you lug it once in a while.

If you want power, just downshift.

[96CX]

Well, I'll have a go at earlier shift points, then. I just filled up, I'll do a tank of shift-to-5th-asap, and see what I get.

Meanwhile, I've got a check-engine light, so I'm seriously considering ordering a scangauge in order to check and reset the codes instead of paying a shop to tell me what the codes are.

[user removed]

I think Advance Auto Parts (and probably others) will read your codes for free. Not meant as advising against getting a scan gauge.

regards
Mech

[MetroMPG]

I'd definitely recommend you get a gauge! I didn't realize you didn't have one yet. It'll turn this fuel saving business into a fun game, and it'll pay for itself. It's a worthy investment, whether you go for the ScanGauge or UltraGauge, doesn't really matter, technically. (I think the UG reads codes too, yes?)

[vskid3]

Regarding not having a tach, a Scangauge/Ultragauge doesn't make the greatest tach because of the lag/refresh rate. Swapping in a different gauge cluster that has a tach would be the best route. I used one from a CR-V in the '97 Civic I had.