Trailers

[RACERSNUT]

While I see a great deal of discussions going on with cars/trucks......aside from the big rig trucks......has anyone done any work trying to get mileage improvements with say a F-250 truck and an enclosed trailer that would haul a race car? For the trailer, I've got in mind your standard 8 ft. tall, 24 ft long everyday variety.

I've search high and low for low-profile trailers,.......and the options seem to be "we'll build whatever you want" or the trailers sold for UBER prices.

Any thoughts or information?

[freebeard]

I've seen a lot posted that could apply. How big a race car? More than one?

I'd look through Buy a Trailer (instead of a pickup truck) or Improving a box cargo trailer . There's a lot on teardrops and Hi-Lows, but you might also find a lot of food for thought in the Tractor-trailer wind tunnel work.



If I don't find it someone will post the white aluminum car hauler with the split open boattail.

[ennored]

What Freebeard alludes to is there's a lot of discussion here about trailers. His threads are a good start. If you add my username to a search here, it might help narrow the results, as I think I've commented on most of the trailer discussions in the last year or two.

(Try this as a google image search: "site:ecomodder.com ennored trailer"...)

[aerohead]

Originally Posted by RACERSNUT

While I see a great deal of discussions going on with cars/trucks......aside from the big rig trucks......has anyone done any work trying to get mileage improvements with say a F-250 truck and an enclosed trailer that would haul a race car? For the trailer, I've got in mind your standard 8 ft. tall, 24 ft long everyday variety.

I've search high and low for low-profile trailers,.......and the options seem to be "we'll build whatever you want" or the trailers sold for UBER prices.

Any thoughts or information?

Do a Search for 'FAIRING WELL',by Christian Gelzer.It's online.
NASA did some research at Edwards Air Force Base and published their findings.
If you're going for really low drag:
*The trailer's upper horizontal edges should be radiused (HAULMARK and CM already do this)
*The trailer's upper contour should be like Don Bur's in Europe
http://www.donbur.co.uk/eng/images/1...-%289rt%29.jpg
*The trailer's rear should be boat-tailed
*Clean up the truck all you can
*Build a bedcover which creates a fairing to direct air onto the trailer (height and width)
*Close the gap between the trailer face and bedcover
*Full belly pan,truck and trailer
*Full-depth side skirts
*Full wheel skirts
*Full wheel covers
*Full wheel fairings
With all these mods you have a shot at a rig with Cd 0.19-0.13,based upon the frontal area of the trailer.

[jray3]

That Don-Bur trailer raises an old question for the pending rebuild of my old and very square trailer. If I increase the frontal area by 'adding a bubble' matching the template atop the original square-edged roof, or for that matter, the sides, would it be reasonable to expect a net improvement? I think so, and cutting down the stout frame of my box-body trailer would be much harder than adding to it (and gaining some storage cavities).

[RACERSNUT]

It seems that I've got some reading to do. Thank you all for the links and references.

I know that most of the big rig trailer information would apply to a plain jane cargo trailer. Although, by the looks of things.......it seems that the general enclosed trailer industry as a whole falls far short of what could be a huge improvement in aerodynamics. Not that I'm opposed to working for something to improve mileage,....but at some point one would think there would be an evolution of sorts. Well at least something more than a V-nose design.

I'm familiar with the template that's offered as a tool. It would certainly be interesting if the Cargo Trailer industry would even consider such a thing.

Again, thanks for the information!

[freebeard]

Thanks again? You make it sound like we're done here. This could run 3 or 4 pages.

So, one car? Not my picture but I saw this at Bonneville salt flats. It's a 50s Spartan with a hatch grafted into the back. It's a car hauler and looks long enough to hold two cars or one streamliner:


http://www.airforums.com/forums/f161/bonneville-salt-flats-59643.html

Radiused edges, aluminum construction—a good start.

Much of the discussion will be matching the drivetrain to the load, search on slowmover and read all his long posts.

[kir_kenix]

How many miles are you planning on putting on annually? Planning on using it for any thing other than a race car? 1 car or 2? I would assume a two 7,000 lb axle 8ft wide trailer...but alot is going to depend on what you are going to be using if for other than towing your race car...and how many miles you are going to put on it. Also, how long do you plan on owning it before you sell it/trade it?

The farm has a 22 or 24' square car hauler that we have had around for probably 5 years. We just use it to haul misc. building supplies, an occasional car/tractor/whatever or for lockable storage on a remote pasture. I doubt it has even 10,000 miles on it, more likely that number is closer to 5,000 even though it is almost constantly "in use". I'd rather not go to all the work to modify said trailer to get better mileage seeing as how few miles it is used annually. Return on investment and reduced trade in for eco-modding it just aren't there for it to be worth the effort.

However, If you are going to pull several thousand miles/year, I would think you would be best served to follow the big rigs. Easily implemented mods (think skirts, fold-able boat tail, smooth wheel covers, gap reduction, softening front radius etc, etc) without drastically modifying the trailer would be your best bet in my honest opinion. I would never buy a trailer that somebody seriously cut into, but I'd be OK with the other mods as long as they were tasteful/removable.

I think if you could narrow it down to: how, how much, what for, and for how long you plan on using the trailer, some of the questions would be easier to answer...both for yourself and others reading the question. If you are going to own the trailer forever and use it for one dedicated use then I'd say tear into that sucker and turn it into a streamlined beast that will likely be more aerodynamic than the car inside of it.

[RACERSNUT]

Sorry, I didn't mean to sound like I was done with the subject......again......I've got some reading to catch up on.

Per my first post, I only plan on modifying a 24 ft. trailer,......maybe a bit shorter. But, something in that length range. I hope to be hauling from the mid-south out to points like Daytona Int'l Speedway, VIR, Mid-Ohio, and Road America. Planning on carrying 1 race car, spare parts, tools, etc.

There's a good point to be made about $$$$ to spend on said project vs. mileage or length of ownership. Additionally, a modded up trailer might not be the best for re-sale. ....if carried to the extreme. That's why I'm so frustrated with the overall trailer industry, and NOT being able to purchase something with some of the modifications already mentioned above. Hell, if these guys were running the auto industry ...we'd still be running points distributors. Again,......something that resembles progress in terms of:

a. Design
b. Materials
c. Construction Techniques

Like most all of the folks here, I share a common goal of making things better and not being satisfied with the status quo.

[freebeard]

For the trailer, I've got in mind your standard 8 ft. tall, 24 ft long everyday variety.

I've search high and low for low-profile trailers

You could get an 8' tall box van and apply some band-aids to it, or you could get a flatbed 24' trailer and build an aerodynamic superstructure.




This is comprised of flat sheets and simple curves. For the sheet material I like PolyMetal and the like. Here is how I would make the edge and corner radii:



On the top piece the edges are captured by an H-channel. Running along the edge, two flanged 45° radii comprise a 90° corner.

What does the F-250 have in/on the bed? The interaction between the tow vehicle and the towed is significant.