help me improve the mileage in my subaru impreza

[bradze]

the nokian eNTYRE 2.0 in 215/55/17 looks like a very good candidate. do only their winter tires have such a low rolling resistance?

[bradze]

im also wondering if anyone made a grill block that doesn't look terrible. i want to make the back of the grill solid so you cant tell.

[spdfrk]

Go for the Hakka r2's. They get better as they wear down as far as efficiency. It's also very hard to shake them loose when brand new. Yeah taller sidewall is better for ride - I'm still on 15's. However the larger wheel means a more vertical sidewall and better for efficiency wheel-turbulence-wise. Check out the youtube video for nokian tire rolling resistance test.

[spdfrk]

If you have a bra on your car, it's easy to slide a piece of black vinyl behind for use as a grille block.

[bradze]

great idea using bra material. anyway ive been looking at a lot of stuff and i dont know if a flat belly pan or removal of my roof rails would be worth it. the car is so new and fuel efficiency was a huge part in the design of the car. i hope i can do something to change the CVT mapping, part of the reason the 2015+ imprezas get 37 mpg hwy instead of 36. of course they also have direct injection.

[spdfrk]

I'd go for the belly pan first. If you do it right, you won't even see it and will make a massive difference. Look at the underside of a Nissan Leaf or the Saturn EV1. There's a reason it's perfectly flat...

As for driving, anticipating and paying attention to everything going on the road makes you a safer driver. It's cheaper not getting into collisions.

[spdfrk]

Also wondering if the Amsoil CVT fluid would help efficiency too... Haven't heard much on that front it it's a massive difference. For automatics using dexron vi/honda z1, ford mercon vi, or toyota ws their low viscosity atf is amazing...

[firehawk618]

Direct injection plays a large part to better economy.

[Ecky]

Generally the greatest-return mods are, in no particular order:

Nut behind the wheel
Tire pressure
LRR tires
Grille block
Belly pan
Roof rack removal
Taller gearing

The nut behind the wheel is where you'll see the largest improvements, and the best way to do that is with instrumentation. Beyond that, a grille block and tire pressure are the easiest and generally cost nothing. If you need new tires, be aware that changing the size will throw off your speedometer. Also, be aware that ceramic brake pads will be more destructive to your rotors, though this might still result in a net savings if it can change driving patterns, as rotors are pretty cheap.

Getting rid of DRLs, and swapping over to HIDs/LEDs will probably disappear into background noise. Electrical load reductions will help in theory, but unless you're trying for an alternator delete, I doubt it'll make any noticeable difference.

[Xist]

I had not seen Dorothy before:

The name Dorothy comes from the lead character in the calssic movie 'The Wizard of Oz,' a young girl swept away to a fantasy world by a tornado.

[emphasis added]
Tornado chasers build armored car named 'Dorothy' they hope will allow them inside twisters | Daily Mail Online

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