Trailer Hitch Boat Tail?

[superchow]

It's the oldest story in the book: Man wants boat tail. Wife doesn't want man to touch car. Man frustrated but understanding.

Man sits down and thinks:

"What if I created a removable boat tail that attaches for highway journeys, but sits in the garage when driving around town?"

Anybody have a trailer hitch and has experimented with that? I have no money for that now, but was wondering if I should focus on such a design at all.

Comments appreciated!

BTW: I was thinking of only a mild boat tail from the trunk lid downward to avoid having to deal with any rear visibility issues on my 07 Civic sedan.

[wagonman76]

I think it is a GREAT idea! For the reasons posted above, plus more.

1. For those of us who arent really into drilling into the car and such.

2. When the boat tail is being worked on, it can be removed rather than have the car unusable.

3. If the boat tail blocks a usable hatchback or trunk, just remove the boattail to get access. This is one thing Ive been thinking about with the Celebrity, Ive thought about a removable hatchback shape but Id want to be able to use my trunk.

One thing to keep in mind is weight limits, check the tongue weight limits in the owners manual. However most boattails shouldnt be heavy enough to be concerned with, since one aspect of ecomodding is to reduce weight.

[Tony Raine]

sounds like a great place to store extra luggage for trips as well.

[MetroMPG]

The removable boat tail is the unicorn of the ecomodding world - right up there with DIY electric hybrid assist (the leprechaun of the ecomodding world? With respect to Mike D's wonderful e-5th wheel, I mean a system integrated into the existing drivetrain).

I don't know anyone who's done it yet. But lots have spoken about doing it...

I'd love to see someone try. It's on my list... but my list grows faster than I check things off.

[MetroMPG]

Removable boat tail

Inflatable boat tail

[superchow]

Thanks for the quick replies. However, as a husband I have more fiscal responsibilities than even the federal government, so I must be able to provide a measurable benefit in the foreseeable future.

Any guesses how many mpgs I could gain from such an undertaking? 2 mpgs? 5? More?

We like to travel fast (and while passing SUVs gloat about still burning half the fuel they are - sorry. ), so consider speeds at or slightly above the limit. We currently get about 37-38mpg on the freeway. 40 mpg would justify the undertaking, 45mpg at high freeway speeds would earn me a back massage from wifey.

"Help me Ecomodder.com, you are my only hope!"

[metromizer]

A friend's dad, a long time Bonneville salt flats racer, built what he called a 'removable shovel nose' for his collectable '65 Corvette. I don't have any pictures, but the scheme went something like this:

He wanted to be able to return the car to it's original condition some day, but toady race it in one of the production classes (no areomods) and also race it in the Lakester class, one that allows some areomods. What he did was add some receivers (like two small trailer hitch receivers) inside the grill area of the stock vette's body. Then he built a light steel framework off those two receivers. From that, he built an areodynamic 'shovel nose' that nestled up against the factory fiberglass body, but wasn't attached to it. the only attachment points were the two receiver pockets, where the afterthought nose bolted on. In fact, he removed the nose every time he transported the car, because it was so low it made it almost impossible to load the car onto a trailer for the journey to Wendover.

[whokilledthejams]

Originally Posted by metromizer

A friend's dad, a long time Bonneville salt flats racer, built what he called a 'removable shovel nose' for his collectable '65 Corvette. I don't have any pictures, but the scheme went something like this:

He wanted to be able to return the car to it's original condition some day, but toady race it in one of the production classes (no areomods) and also race it in the Lakester class, one that allows some areomods. What he did was add some receivers (like two small trailer hitch receivers) inside the grill area of the stock vette's body. Then he built a light steel framework off those two receivers. From that, he built an areodynamic 'shovel nose' that nestled up against the factory fiberglass body, but wasn't attached to it. the only attachment points were the two receiver pockets, where the afterthought nose bolted on. In fact, he removed the nose every time he transported the car, because it was so low it made it almost impossible to load the car onto a trailer for the journey to Wendover.

Wow, that's really inventive. I like it!

I've considered a single-wheel trailer, but actually finding a double-hitch that will attach to the xB without custom fabrication is pretty much out of the question.

Alternately, one could fab up a lightweight Kammback or boattail that straps to the hatch or trunklid. It wouldn't be perfectly ideal, but it would be at least as good as a trailer.

[MetroMPG]

Originally Posted by superchow

We currently get about 37-38mpg on the freeway. 40 mpg would justify the undertaking, 45mpg at high freeway speeds would earn me a back massage from wifey.

"Help me Ecomodder.com, you are my only hope!"

Funny

When you consider that my "partial boat tail" - the permanent Kammback I'm constructing - was worth a 2.3% mpg increase at 55 mph in cruder prototype form, I think a larger, more complete boat tail could double that at least. So, I don't think +2 mpg is a stretch. Not quite back massage territory though.

The challenge for you is that your car is a notchback. You've got flow separation happening part way down your rear window. Ideally you want a boat tail to be a surface that shepherds already attached flow down toward a point. This will be much harder to do on your car than on, say, a hatchback.

You could just accept that there will be an entrained vortex at the base of the rear glass and hope for reattachment on the extended decklid/boat tail, but it's not as good as the full meal deal.

[superchow]

I find the idea of the "strap to the hatchback/trunk" boat tail even more cunning. I have a bicycle carrier that could be repurposed...

Yes, providing a full boat tail starting half way down the rear glass would be preferable... But then the trunk may not be accessible.

By end of October I will have my very first garage (with house attached ). And as you all probably know the pacific NW is probably the best place in the lower 48 for extended indoor winter month projects. Will revisit this possibility when I have room to tinker.

2 mpg... I think that this could be worth the effort. Especially considering the aero results from Blue07CivicEX.