35,000 Mile Road Trip - Want to do some small mods - Fuel Economy, Hypermiling, EcoModding News and Forum

johnny_261 · 03-05-2014, 05:38 PM

Hi Everyone,

I'm new to this forum and have joined because I'm planning on going on a ~4-5 month road trip across the USA (leaving in mid April). Seeing as well be doing a LOT of driving, I thought it might be a good idea to do a few small mods to try to increase the fuel efficiency of the vehicle (even if only by a little bit)

Unfortunately, my car is NOT fuel efficient to begin with...it is a 2004 Kia Sorento EX with a 3.5L V6. We will also be bringing a rooftop carrier, which I know will not help fuel efficiency at all, but we need the space. I'm debating whether to get one of the tow hitch mounted racks, but the problem is we would also have to get a tow hitch installed and buy the rack making this option quite a bit more expensive...We will be doing a fair amount of city driving as well as we plan on visiting all the major cities and therefore, this might make it harder to park etc...

I was thinking of doing some smooth wheel covers for the front wheels, rear wheel skirts for the rears, perhaps a belly pan, but I'm not sure if the effort for this one will be worth it. The car also came with a small rear spoiler, I'm thinking taking it off would be better for fuel economy? Also going to try to reduce weight by taking out the rear seats.

Does that sound like a good start?

I was also wondering if mounting the roof top carrier closer to the front or rear of the car would make a difference? Also, would having something to cover the gap between the top of the car and the bottom of the carrier help aerodynamics?

Thanks for any input.

echo-francis · 03-05-2014, 05:51 PM

I would begin with a mpg gauge, a grill block , smooth wheel cover, partial belly pan (front bumper to front wheels and rear wheels to real bumper) with tire spats , max psi (on tire) and drl switch or disable

Frank Lee · 03-05-2014, 06:38 PM

I'd put more effort into finding an alternative to using the roof carrier; if you come up with one then a roof rack delete is in order if you have one.

None of those other things- even all added together- is going to even come close to cancelling out the bad effects of a rooftop carrier.

What I did with Moon Unit was internet shop for hitches; for me nobody even came close to the good deal I got from U-Haul. Not only that, I brought my tools, work clothes, and a piece of cardboard to lay on to the U-Haul store and installed the hitch myself out in the parking lot, and it was a piece of cake. IIRC it was a little over $100 total.

Perhaps you can estimate the mileage hit you take with the rooftop carrier and multiply that over 35k to come up with how much you can spend on a hitch and hitch carrier and still break even. Of course, you will still have those items for use after the trip as well. And if you don't want them after the trip they should have a good bit of resale value left.

With a hitch carrier you even have the option of cloaking it- possibly with coroplast- into a faux boattail, where you'd have a shot at improving fe.

johnny_261 · 03-05-2014, 06:51 PM

Quote:

Originally Posted by Frank Lee

I'd put more effort into finding an alternative to using the roof carrier; if you come up with one then a roof rack delete is in order if you have one.

None of those other things- even all added together- is going to even come close to cancelling out the bad effects of a rooftop carrier.

What I did with Moon Unit was internet shop for hitches; for me nobody even came close to the good deal I got from U-Haul. Not only that, I brought my tools, work clothes, and a piece of cardboard to lay on to the U-Haul store and installed the hitch myself out in the parking lot, and it was a piece of cake. IIRC it was a little over $100 total.

Perhaps you can estimate the mileage hit you take with the rooftop carrier and multiply that over 35k to come up with how much you can spend on a hitch and hitch carrier and still break even. Of course, you will still have those items for use after the trip as well.

With a hitch carrier you even have the option of cloaking it- possibly with coroplast- into a faux boattail, where you'd have a shot at improving fe.

You're right - it probably wouldn't be that expensive and given that a rooftop carrier will probably kill the mileage quite a bit, I'm sure it will pay for itself over the course of the trip. The only thing that I'm hesitant about is that it will probably limit our access to the rear trunk which might be a real hassle since we will constantly be loading and unloading stuff at our stops. The other thing, as I mentioned before, is city driving and parking...but we could probably learn to live with that.

Frank Lee · 03-05-2014, 07:04 PM

You have a 4-door, possibly with no back seat. Couldn't you access the "trunk" easily through the rear doors? Would it be worse than the access to a rooftop carrier? Why all the stuff handling at stops?

UltArc · 03-05-2014, 07:10 PM

If you have a co pilot, it seems well worth it to use them as a spotter utilize the trailer hitch. And if you are visiting larger attractions, they usually have more user friendly parking- Chicago Museum of Art had underground parking, Metroflex had a dirt field, when I did my adventure.

All points above are valid. There are two ways to do modifications: maximizing return on investment, and maximizing appearance. Elbow grease and efficient scavenging/purchasing is best for ROI. Keep in mind many builds have calculated pay offs in them, but are planning on a few thousand miles. You know right now 35k miles. On a vehicle with such poor aero to start, differences will mean more, and most definitely pay off. I would advise packing some extra supplies- specifically zip ties and scissors. Every modification I have on each of my vehicles can be removed or mended with these two tools, which is another perk to making ROI a main focus and avoiding complexity.

Another perk you have for this circumstance is higher ground clearance. I can't fit my body under the Mustang, and can't get my shoulder under the Insight. Replacing the starter under my S10 Blazer in a Home Depot parking lot was cake because of ground clearance.

sheepdog 44 · 03-05-2014, 08:42 PM

Best case EPA numbers 14 City, 16 Combined, 18 Highway. If it's all highway miles a 1mpg increase is: (35000 / 18 x 3.5) - (35000 / 19 x 3.5) = $358 saved. Anything to help will save a lot of money.

Best advice is to adjust the nut behind the wheel and drive slower. Doing 5 or 10 under the speed limit in top gear will net the most percentage increase in mpg aside from aeromodding. It might also help the sightseeing!

The more people you have to split the gas bill the more economical the whole trip will be. A few people will raise the effective mpg per person of the vehicle.

redpoint5 · 03-05-2014, 09:30 PM

Congrats on the trip! I'm jealous... I can only manage to get 5 days for a road trip.

I'd sell the car and buy something more fuel efficient that will still serve all of your needs for both the trip, and normal driving. You're looking at a $6,800 fuel bill as it is. If you drove something that got 30mpg, your bill would be $4,100, or $2,700 less expensive.

What are you bringing that requires a rack? If it's just 2 people going, and the rear seat will be removed, perhaps you can fit everything inside the car. This will be more secure and save you tons of gas money.

Here's a guy that turned his Prius into a road trip champion by removing the rear seat and building in storage/sleeping space.

http://www.youtube.com/watch?v=lPFicO_I86c

igo · 03-05-2014, 10:31 PM

That prius set up for car camping is awesome! I have done some car camping in the Xb but it's not quite long enough to fully stretch out in the back unless you sleep diagonal.

As for the original post...I say lose the roof rack!

johnny_261 · 03-06-2014, 12:18 AM

Thanks for the input guys - really appreciate it.

Selling the car is not really an option right now - I still need an SUV for day to day after the trip as I often am lugging stuff around. Also, the car is in extremely good condition and low km's so I know I'm not going to enough $ out of it's sale compared to what it will cost for a comparable condition/KM's more efficient car.

The reason why we need the extra storage (i.e the rooftop or cargo hitch) is because we will be sleeping in the trunk of the car - similar to the Prius video posted. We have to pack enough for 4-5 months, including supplies to camp, emergency supplies, tools, etc and we're probably going to be buying a lot of crap along the way, so we will need extra storage for sure. We did a 2 month road trip with a slightly bigger SUV a few years back and the car was packed full with stuff i.e. no room to sleep in the back. So I know from experience that we need the extra space.

I'm leaning towards the cargo rack right now, since I do think it will make a really big diff in MPG.

Also, one of the questions in the original post was should I remove the rear spoiler? Thoughts on this?

Again, thanks for the input. Getting so excited to hit the road.