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Went okay, as I am not perfect with driving stick yet, but still, significantly below EPA. Any suggestions as what to look for? The set up is as follows: oil is synthetic 5W-30, new air filter and spark plugs, new front and rear brakes, new tires, which are larger than stock though, tires are at 36 PSI.

Driving habits wise, I'm shifting at ~2250 RPM when the road is clear behind, or ~2750 if there is traffic behind or on freeway entrances. Cruising at ~55 according to in car speedometer, which is under reading by 3%. Trying to DWL, but without instrumentation is somewhat tricky. I need to keep my foot very steady.

Still, my goal is to achieve EPA combined(55 MPG) at least in this car, so I'm a little concerned that I'm 8-9 MPG below it. I'm hoping its just the new tires and brakes that need to wear before they reach their full potential.

Have you accounted for the difference in revs/mile of new vs stock tires? Perhaps that is tied to the 3% you mentioned.

What is max sidewall of new tires?

Are you FASing?

Maybe shift lower still when conditions allow?

Smooth idle on warm engine?

No drag feeling when gliding?

2000 RPM should be about your top level for shifting (unless P&G -- that's a different story). For easy acceleration you should be able to shift down in the 1800 RPM range without issue. In my Elantra and Insight I regularly shift at less than 1500 RPM and use 2000 RPM when climbing decent sized hills.

As Sean says, 2000 rpm should be your max rpm in any gear except top (fifth?) gear. Acceleration should be modest. and you should coast as much as possible.

What about MPGuino?

Thanks for the tips everyone. I was looking for more mechanical tips, as in things that might be hindering FE on a 16 old car that was not used much, or only for short distance, cold engine driving. Do you think changing the O2 sensor might be of use? Do they die from pure age as opposed to miles driven?

Have you accounted for the difference in revs/mile of new vs stock tires? Perhaps that is tied to the 3% you mentioned.

What is max sidewall of new tires?

Are you FASing?

Maybe shift lower still when conditions allow?

Smooth idle on warm engine?

No drag feeling when gliding?

Well, the stock tires are P145 80 R12, and the current tires are P155 80 R12. The tires that came with the car were in bad shape, and finding the R12 tires itself is a big challenge these days. Even to find the P155 80 tires, it took alot of searching online and eventually were ordered from eBay. In fact, installing them was also a pain as because they are not stock sized, most shops refused to install them, at least with the wheels on the car. So, no, I have not accounted for the 3% under reporting in my mileage, but that isn't a huge difference either way.

The max sidewall is 44 psi. I am running 36 psi partly because I'm still getting used to the noiser/harsher ride of this car. I might increase it later. The other thing is, the tires look slightly bulging outward. This is the first pair of tires on which I have ever seen this happen though, and it might be because they are still new. However, my goal with this car is to get EPA mileage, I'm not particularly looking for above EPA as I was in the previous car. The recommended tire pressure is only 32, which is what I assume the EPA tests it at.

No, I'm not FASing. I'm still learning to drive stick, so I'm not comfortable with FASing, even at stop lights, yet. It takes me a little while to get it in gear still.

The engine does seem to be idling smoothly, although it seems high. If I put it into neutral at speed, or push in the clutch, it seems to want to idle at ~1250 RPM. However, at a stop, it will drop down to a normal 750. I'm not sure why this is.

The glide distance does seem pretty short, I'm not sure if its just the fact that its a smaller car, or the lower tire pressure, or maybe the brakes are dragging. Unfortunately, the rear drum brakes are not adjustable in this car, and are only "self" adjusting. I can adjust the parking brake, which seems fine as I get about 9-11 clicks. The front brakes of course are disc brakes which are all "self" adjusting.



2000 RPM should be about your top level for shifting (unless P&G -- that's a different story). For easy acceleration you should be able to shift down in the 1800 RPM range without issue. In my Elantra and Insight I regularly shift at less than 1500 RPM and use 2000 RPM when climbing decent sized hills.

Keep in mind that this engine produces only 49 HP, (30 HP/100 lbs) :D. I have tried shifting at around 1750 RPM or so, and it works fine in residential areas where the PSL is 25. But, and this might be because I'm still a beginner, even on a 40 PSL road, If I shift around 1750, I'm not able to apply enough throttle to accelerate up to 35 MPH or so without lugging. Usually in 3rd I need to take it up to 2000 before I have enough torque in 4th. I still need to experiment with this more though.

When others are behind though is another story. Partly because I'm still taking like ~10 seconds to engage 1st gear from a stop, I am accelerating more rapidly to compensate for that to avoid getting hit from behind. But even going up to 2750 RPM in this car is about as fast as shifting at 2000 RPM in the Mitsubishi.



As Sean says, 2000 rpm should be your max rpm in any gear except top (fifth?) gear. Acceleration should be modest. and you should coast as much as possible.

Yes, 5th gear is top gear, and I definitely need to exceed 2000 RPM in 5th gear. I have a freeway section with a PSL of 65, and I turn 2000 RPM at only 40 MPH in 5th gear :eek:.



What about MPGuino?

I have thought about it, but at this point I'm not yet sure I want to shell out the money/time to get one of those and install/assemble it.

That's not much horsepower but I know where you are coming from having driven a '70 VW bug for a few years. My Insight (67hp) probably isn't far from what you see in terms of power either. Perhaps you just aren't used to how slow these vehicles accelerate?

Regardless, persevere! :thumbs_up:

I'm not much of a wrench, but I'd raise it and make sure the rear wheels spin freely, given your statement that it doesn't glide well. That and keep working on the shifting. Perhaps alternate routing can alleviate some of the traffic issues with shift points.