Full-boat-tail trailer with gap-fillers for Toyota T-100 pickup

[euromodder]

Originally Posted by aerohead

I've had significant wind the whole way and don't expect to learn much from the first tank.

Don't you have windy tanks on record to compare this one to ?
Windy days is when a streamliner should shine - if not in absolute numbers then at least in relative mpg numbers.

The rig is AOK,she pulls beautifully,the wheels are still on and no other parts have gone missing.

Good to hear that.
Let's hope they stay safely put for the whole trip.

Bonneville is already history.I'll change my handle from aerohead,to Mr. Yearfromnow.
All I can do is try again for next season.It's a tough one to swallow.

Sorry to hear the Bonneville attempt has fallen through after all the work you've done.

Let's hope the truck stays good for another year.

[KamperBob]

Originally Posted by aerohead

I'm reporting in from a motel lobby in Santa Rosa,New Mexico.I finally left Denton late this morning.I drove 'til dark,110-miles short of Albuquerque,my first scheduled fuel stop.I've had significant wind the whole way and don't expect to learn much from the first tank.
The rig is AOK,she pulls beautifully,the wheels are still on and no other parts have gone missing.
Nothing is complete,just the pick and shovel stuff.I had 938 man-hours into her at the time I hung the tools up yesterday.I won't even guess at how much time it will take to actually 'complete' her.
Perhaps if the winds will subside,I'll get some useful quanta.

Bonneville is already history.I'll change my handle from aerohead,to Mr. Yearfromnow.
All I can do is try again for next season.It's a tough one to swallow.
I'll try and post as trip progresses.
I shoot for Utah tomorrow,and into Reno,Nevada the following day for a few days visit with family,then head for Colorado to see about Gary's Prius trailer project.
Catch you all later,aero.

In spite of Bonneville itself this year may your journey be enjoyable, safe and gratifying.

[bondo]

I feel your disappointment especially after all the hours of work you put into the vehicle. I too am used to disappointment but you always keep going. Many of us here are behind what you are doing 100%.

At least you are not a talkerdonothingexpert which, frankly, there are too many of.

Bondo

[aerohead]

Made it back last Sunday afternoon.4,212-miles.Only casualty was a spring cap,lost at Bonneville,on the service road to pit area.Both wheels remained for the duration ( a record in itself!).
I got an official weight for the rig,attempted three times to photograph it from the Opera House to no avail,and ended up doing a photo shoot of the complete dis-assembly and detachment.She goes back into the shop before the scheduled rains this weekend.
I've been capturing topographical data off the internet to help make sense of the test results.
The 'rig' was 680-lbs ( 309 kg ) heavier than last year,and over 1,300-lbs (590-kg) heavier than stock.
I'm going over log-books dating to 1994 for comparative data.
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I want to thank everyone for their words of encouragement,it means a lot.When the temperature finally broke I went to 14-hour days trying to pull the silly thing together and was overtaken by the calendar.
If I didn't go,I wasn't going to get to go,so I went ,un-finished ( sounds familiar ) to salvage what I could.
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I'll work tonight and come in tomorrow with more complete noodling.
Overall,I'm very pleased with the project.
As the gap-fillers are yet un-finished,there is potential for better numbers ahead.
With the 2009 damage also un-resolved,this too holds some promise of even better results.
The planned,but unrealized front wheel skirts should also improve the equation.
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I did set an all-time new best mpg record for the T-100,pulling the trailer ,almost 9 mpg better than my previous best for the truck.It's a 'conditional' victory,more on that tomorrow.
In some instances she showed worse,in some instances better.
The overall trip average was better than last year without the trailer,however I limited my cruise speed to only 65-mph,whereas,last year I cruised at the posted speed limit ( up to 75 mph ( 120 k/h).
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I pulled to as high as 85-mph (136 k/h) during passing maneuvers,she's rock-solid,tracks perfectly.
I visited with Purvis Bearing Company today,here in Denton,and they feel I can run to speeds which limit hub temperatures to 200-F.
I need to test at higher velocities.I'm very suspicious of BSFC affects,and I want to 'load' the engine and see what ,if any difference it might make.
85-mph was effortless,the truck could easily use a 6th and maybe a 7th gear.
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I'll grind numbers tonight and catch up tomorrow with more thorough results.If I had to say anything,I'd say that in it's present,un-finished condition,the trailer is aerodynamically invisible.We'll talk about grade effects tomorrow.Al's closing shop in a few minutes,see you then.

[orbywan]

Originally Posted by aerohead

I'll grind numbers tonight and catch up tomorrow with more thorough results.If I had to say anything,I'd say that in it's present,un-finished condition,the trailer is aerodynamically invisible.We'll talk about grade effects tomorrow.Al's closing shop in a few minutes,see you then.

Good stuff Phil, looking forward to reading the results. +9mpg is pretty cool!

[Cd]

Phil I know the Texas Mile is not long enough of a track to attain full speed, but wouldn't it be useful somehow ?
It's less than two hundred miles from your house.

[Varn]

9mpg improvement is nothing to sneeze at. Why don't you post your mileage?

[aerohead]

Originally Posted by Cd

Phil I know the Texas Mile is not long enough of a track to attain full speed, but wouldn't it be useful somehow ?
It's less than two hundred miles from your house.

With the low power I need all the distance I can get to the mile trap.
At Bonneville there's always a slim chance that I can run the long course,which is 6-miles of W.O.T. acceleration.
Low power streamliners need all the room they can get to reach terminal velocity and Texas Mile just doesn't allow for that.My neighbor Charles Farmer has the 'Yellow Submarine',Ford SHO-powered streamliner,and he has used Texas mile regularly for fuel system checks but couldn't possibly 'see' the cars potential without the Salt Flats.
I'll have reason to be going to Alpine,Tx for astronomy and may go by the Texas Mile just to look,but I really can't see it as a resource for what I'm doing.
Conversely,I am now very interested in buying some wind tunnel time at GM.The road-testing is extremely problematical for data acquisition,and each year I appreciate the value of large-scale tunnels,even at $2,000/hour.

[aerohead]

Originally Posted by euromodder

Don't you have windy tanks on record to compare this one to ?
Windy days is when a streamliner should shine - if not in absolute numbers then at least in relative mpg numbers.


Good to hear that.
Let's hope they stay safely put for the whole trip.


Sorry to hear the Bonneville attempt has fallen through after all the work you've done.

Let's hope the truck stays good for another year.

Wind in Texas can have extreme variability:direction and amplitude,varying with location in real time.Without on-board data acquisition it would be virtually impossible to 'know' what was happening 'outside' the vehicle.
Throw in grade effects,curve resistance,etc. and you've got such a can of worms,it would be impossible to make any sense of it.
That's why the SAE is very prudent about road-testing:
*Flat roadway
*No grade
*No wind
*No rain or other precipitation
*No curves
*Constant velocity
*Fully warmed up (22-miles at 50 mph)
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For us,maybe all we can expect,is that over a long series of tests,a 'trend' emerges from the signal-to-noise ratio of the data scatterplot.
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On the Denton-to-Albuquerque leg I'd never made this run with the trailer.With the topography of the route and wind spectra I knew I was going to be hammered at the gas pump.This turned out to be my lowest MPG tank.So I guess that.intuitively my senses were correct.
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Check the data for this tank in the up-coming post and you can see what I was facing.

[aerohead]

First of all,I had a 5-hour phone conversation with the Femmebot last night so I'm not as far along with the data as I would like.
And I'm close to the deadline for my income tax and will have to re-direct my energies for awhile.
Here's some of what I've gleaned so far.
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From the log-book:
*Tank#1 Denton-Albuquerque,NM,65 mph cruise,76 mph max velocity,moving ave.62 mph,-------------------- 28.753 mpg ( more details later )-----------
*Tank#2 Albuquerque-Green River,UT,65 mph,80 mph max velocity,
------------------------------- 31.749 mpg -------------------------------
*Tank #3 Green River-Lake Side,UT (Tooele ),65 mph cruise,71 mph max velocity------------------------ 30.909 mpg -------------------------------
*Tank#4 Lake Side-Salt Flats,UT,65 mph cruise,71 mph max velocity
------------------------------- 29.583 mpg --------------------------------
*Tank#5 Salt Flats-Winnemucca,NV,65 mph cruise,75 mph max velocity
-------------------------------- 31.625 mpg -----------------------------
*Tank#6 Winnemucca-Carson City,NV-Winnemucca,65 mph cruise,75 mph max velocity
-------------------------------- 30.842 mpg -----------------------------
* Tank#7 Winnemucca-Salt Flats,65 mph cruise,75 mph max velocity
-------------------------------- 31.781 mpg------------------------------
*Tank#8 Salt Flats-Lake Side,65 mph cruise,69 mph max velocity
-------------------------------- 30.674 mpg -----------------------------
*Tank#9 Lake Side-Green River,65 mph cruise,77 mph max velocity ( moving ave 57 mph)
-------------------------------- 31.282 mpg -----------------------------
*Tank#10 Green River-Exit#149,Colorado Springs,CO,65 mph,79 mph max velocity
-------------------------------- 28.868 mpg ( details later)----------------
*Tank#11 Colo,Sprgs-Trinidad,CO,65 mph,85 mph max velocity
-------------------------------- 47.923 mpg -----------------------------
*Tank#12 Trinidad-Dona Ana,NM,65 mph cruise,79 mph max velocity
-------------------------------- 32.63 mpg ------------------------------
*Tank#13 Dona Ana-Cloudcroft,NM,65 mph,72 mph max velocity
-------------------------------- 30.452 mpg -----------------------------
*Tank#14 Cloudcroft-Artesia,NM,55 mph cruise,62 mph max velocity,52 mph moving ave.
-------------------------------- 33.699 mpg -----------------------------
*Tank#15 Artesia-Denton,TX,55 mph cruise,63 mph max velocity,moving ave. 53 mph
-------------------------------- 33.918 mpg -----------------------------
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Total trip: 4,212-miles,134.178 gallons,31.391 mpg ave.
65 mph portion---------------------- 31.046 mpg ave.
55 mph portion---------------------- 33.882 mpg ave.
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Denton-Albuquerque:28.753 mpg
One-way
613-miles
7,915-feet vertical ascent
3,665-feet vertical descent
41 topographical reference points
1 overnight stay with cold restart,low 50s F
N wind ( windmills pumping,flags straight out,wind generators operating)
Stop signs,stop lights,traffic,road construction delays
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Green River-Colo.Springs: 28.868 mpg
One-way
411-miles
11,304 feet vertical ascent
8,990 feet vertical descent
37 topographical reference points
Stops,traffic,road construction delays
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Colo.Springs-Trinidad: 47.923 mpg ( new record )
One-way
135 miles
2,029 feet vertical ascent
2,449 feet vertical descent
10 topographical reference points
45-degree F/high 70sF
26-mph N wind ( perfect tailwind)
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Old Record: 39.131 mpg
Roundtrip,Lindsay,TX-Electra,TX
200-miles
45 mph ( WW-III Emergency National Fuel Rationing speed limit )
869 feet vertical ascent
869 feet vertical descent
11 topographical reference points
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General observations:
The data comparisons in some cases are apples and oranges due to different test velocities.
This year,with the trailer,MPG was better than last year without the trailer,but overall maximum cruise velocity was lower by 10-15 mph depending on the segment.
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The Cloudcroft-Denton 55-mph testing will be a continuing protocol and I did have results for past years (this run is where the CRX scored 82 mpg at 55-mph in 1995 ).
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For Artesia-Denton:
This year,with the 682-lb weight penalty,the 33.918 mpg is lower than last year's 34.264 mpg without the trailer,although,was 2.105 mpg better than in 2009 when I made the same run,also,of course,without the trailer.
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There is more data,but I'm kind of burned out right now and I'd like to catch up on other's threads.
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Loose conclusions:
On flat land the trailer should be zero mpg liability.She weighs as much as the 'production' trailer,with a complete Nissan Leaf Lithium ion pack [410-lbs (186kg)].
It should be possible for a plug in EV to pull the trailer,containing a second pack and double its range ( highway only!).
When 'finished' she may show a net 'gain.'
Mountain driving shows a penalty I think.
It would be instructive to take a bone stock T-100,strap on the trailer with no other mods and see what it would do by itself.
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I'll add data as time permits.
She's still an unknown quantity,but the 47.9 mpg run illustrates the relative importance of streamlining.Getting the Cd down lower will be the same as a continuous tailwind when on the highway.See you all later.