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So here is my first post. I'm just getting into the hypermiling gig and have a quick question. It should be an easy one for the FE guru's here. I currently own a 01 Mitsubishi Mirage with an automatic transmission. I currently get 35mpg.

The tires I am running on are already descent as far as rolling resistance goes (Sumitomo HTR 200). I was thinking about getting lighter wheels to increase my FE. There is obviosly fuel to be saved by lowering the total wheel weight....but how much?

My current steel wheels weigh in at a porky 20lbs each! I was thinking of getting some aftermarket aluminum rims that weigh 12.8lbs each.

With a savings of about 7lbs per wheel...would I notice much of a FE improvement? Are we talking like a 2mpg increase? Or would it be more like 0.2? I was wondering if anyone has first had experience with this.

If the fuel savings are that minimal, it might not be worth it for me to justify the $500 purchase.

Thanks in advance! :woot:

If the fuel savings are that minimal, it might not be worth it for me to justify the $500 purchase.

Thanks in advance! :woot:


Never mind the actual improvement. It is "The Perfect Excuse"!

But I just read about the upcoming VW Golf/Rabbit diesel hybrid.

It has partially blocked alu rims because the open spoked rim design is aerodynamically inferior. To keep the fancy look they had painted black parts of the rims to fake the spoke-like appearance :)

True, it is the perfect excuse. But I could think of plenty of other things to spend my money on if it didn't give me any better FE. Anyone have any idea of the FE gains I might expect?

True, it is the perfect excuse. But I could think of plenty of other things to spend my money on if it didn't give me any better FE. Anyone have any idea of the FE gains I might expect?

Depends on the weight of the car - but I wouldn't expect more than half a percent - so like, 0.15 MPG improvement.

If you couple the new rims with some Lrr tires it could make a couple mpg difference. When I put the wheel and tire package on my Saturn I had to completely redo all of my glide/speed points because I kept coming in to hot to corners and turns.

If lighter weight, more aerodynamic wheels weren't effective at increasing FE, Honda wouldn't have bothered with them on the Insight, or on the HCH-1 and HCH-2. Clearly wheel design has some significant effect.

For a cheap, easy fix, get some moon-style hubcaps - the flat, spun aluminum covers. Looks kinda silly but very functional.

I swapped my OEM steel wheels with hub caps for new alloy wheels that were about 5 lbs. less each. Unfortunately it was at about the same time that the temperatures started to drop, so it was hard to tell what difference there was to FE, if any.

Once it warms up we'll see if I can exceed the 42 mpg I was able to get last summer. The new wheels are certainly not as aerodynamic, so I'm guessing the weight savings won't add much FE. But they do look nice, which is why I got them in the first place.

How about "Thinner" Wheels? Current mine are 15x5, 185/65/15... I want to retro fit a lighter wheel and thinner, to lower my rolling resistance. Any advice?

I hope it doesn't rain because I'm handicapped enough as it is, driving in LA.

Wheel weight would have the greatest effect on FE in stop and go driving and would have minimal effect in highway driving.

I'm with Basjoos on this one.
Re: Narrow tires. Actually, sidewall flex affects FE more than tire width. That's why maximum pressure is effective. Has anyone played with larger rim size to shorten the sidewalls? Any measurable mpg difference?

Keith