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Old 11-20-2013, 10:07 AM   #81
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As you experienced, bungee cords are NOT the strongest, and stretch in high wings giving the potential under certain conditions to unhook, in the exact same manner as when you manually stretch it to unhook it. But unlike something like kakyaks, a hood on the roof at 60 mph is going to take much more wind pressure lifting it off, much much more than something like a kakyak.
Needs to be tied down with nylon cord, and double tied. It will not fly off that way, but just in case the tow line will catch it instead of breaking someones windshield, paint damage, auto accident--and big expenses.
Yea exactly. Thanks for the idea.
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Old 11-20-2013, 10:33 AM   #82
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If you plan to tie your hood on the racks then tie the hood with another rope to the roof (through the windows).
The roof racks are rated for about 40 pounds(I don't remember the exact numbers), and held by 4 bolts only.
In case of a wind spike the hood can pull the racks rails off the roof and make itself a kite.
So, hood tied on the roof racks and extra rope through the windows would be a better idea.


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Old 11-20-2013, 10:35 AM   #83
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Adding To the above. You and your friends will have to endure the wind noise as you will have a small gap in the windows to let the rope through.
Take a trial run first. You don't want to damage the rubber seals in the windows. So make sure that idea works.


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Old 11-20-2013, 10:38 AM   #84
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Adding To the above. You and your friends will have to endure the wind noise as you will have a small gap in the windows to let the rope through.
Take a trial run first. You don't want to damage the rubber seals in the windows. So make sure that idea works.


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Will do, thank you.
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Old 11-20-2013, 10:49 AM   #85
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OR in the alternative, or in addition--when I use to put a small sail boat (sunfish) on the roof and drive 100 miles, I would tie each corner of the object (boat in this case) with a line to the corner of the car and attach it to the car bumper. (Need to bring towels to wrap the cord with where it touches the paint on the body of the car.)
Good point, that the racks are made to carry something like 40 pounds OF DOWN FORCE. We are NOW talking of UP FORCE as if it was a sail. I am not a engineer, but it probably is well over 200 pounds, maybe 500 pounds of UP force at 60 mph.
Lastly, if the old hood has not value to you (since you are going for a new one) why not just dump it at a junk yard down there and not transport home.

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Old 11-20-2013, 10:55 AM   #86
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OR in the alternative, or in addition--when I use to put a small sail boat (sunfish) on the roof and drive 100 miles, I would tie each corner of the object (boat in this case) with a line to the corner of the car and attach it to the car bumper. (Need to bring towels to wrap the cord with where it touches the paid on the body of the car.)
Good point, that the racks are made to carry something like 40 pounds OF DOWN FORCE. We are not talking of UP FORCE as if it was a sail. And not a engineer, but it probably is well over 200 pounds, maybe 500 pounds of UP force at 60 mph.
Lastly, if the old hood has not value to you (since you are going for a new one) why not just dump it at a junk yard down there and not transport home.
I would like to keep it for future use as I am getting a GTR style hood and may not always be a fan of the vents. I like the vents now, but I am looking ahead and know that I might get tired of them.
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Old 11-20-2013, 11:06 AM   #87
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Re: - Driving Without A Hood -

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I would like to keep it for future use as I am getting a GTR style hood and may not always be a fan of the vents. I like the vents now, but I am looking ahead and know that I might get tired of them.
Do you have any friends that own trucks and might help you out if you buy gas and a lunch? That would be the ideal solution with no risk of anything bad happening

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Old 11-20-2013, 11:09 AM   #88
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Do you have any friends that own trucks and might help you out if you buy gas and a lunch? That would be the ideal solution with no risk of anything bad happening

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Honestly, I really want to take my car and take pictures along the way. After all the comments and opinions I am confident that it will be ok and if it ends up not being ok then that's how it is and I'll deal with it.
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Old 11-20-2013, 11:23 AM   #89
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OR in the alternative, or in addition--when I use to put a small sail boat (sunfish) on the roof and drive 100 miles, I would tie each corner of the object (boat in this case) with a line to the corner of the car and attach it to the car bumper. (Need to bring towels to wrap the cord with where it touches the paid on the body of the car.)
Good point, that the racks are made to carry something like 40 pounds OF DOWN FORCE. We are not talking of UP FORCE as if it was a sail. And not a engineer, but it probably is well over 200 pounds, maybe 500 pounds of UP force at 60 mph.
Lastly, if the old hood has not value to you (since you are going for a new one) why not just dump it at a junk yard down there and not transport home.
Yes, downforce is a good thing with a roof-mounted hood! Forgive the pilot talk, but you want to create a negative angle of attack to the relative wind. In profile, the leading edge of the hood should be lower than the trailing edge. Maybe shim up the back with some cardboard to give it this forward rake. Lash it down properly and you'll be fine.
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Old 11-20-2013, 11:31 AM   #90
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Yes, downforce is a good thing with a roof-mounted hood! Forgive the pilot talk, but you want to create a negative angle of attack to the relative wind. In profile, the leading edge of the hood should be lower than the trailing edge. Maybe shim up the back with some cardboard to give it this forward rake. Lash it down properly and you'll be fine.
Good idea and the natural curve of the hood should already provide a slight downward angle. But like you said, making it more dramatic would be good.
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Old 11-20-2013, 03:51 PM   #91
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Also block off the grilles. Don't want any air getting underneath the hood at speed while it's on the roof rack.
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Old 11-20-2013, 05:33 PM   #92
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Also block off the grilles. Don't want any air getting underneath the hood at speed while it's on the roof rack.
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Old 11-20-2013, 06:15 PM   #93
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I say drive without a hood because you can. People do it all the time and I wouldn't hesitate to do it.
If you're planning on tying to the roof though try using towels or something as a spacer so that the hood is angles downward as to create downforce instead of upforce. Also, please don't bother with rope. Buy proper tiedowns with ratchets. Those will not come undone no matter what. Your rack will fly off before those come undone.
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Old 11-20-2013, 06:18 PM   #94
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OR in the alternative, or in addition--when I use to put a small sail boat (sunfish) on the roof and drive 100 miles, I would tie each corner of the object (boat in this case) with a line to the corner of the car and attach it to the car bumper. (Need to bring towels to wrap the cord with where it touches the paint on the body of the car.)
Good point, that the racks are made to carry something like 40 pounds OF DOWN FORCE. We are NOW talking of UP FORCE as if it was a sail. I am not a engineer, but it probably is well over 200 pounds, maybe 500 pounds of UP force at 60 mph.
Lastly, if the old hood has not value to you (since you are going for a new one) why not just dump it at a junk yard down there and not transport home.
Wait what?! Why are you saying it will have 500 pounds of upforce? That's nuts.
First, you do not know the angle in which the hood will be placed. And aerodynamic force is calculated by surface area, angle, and wind speed. Not weight of the object. A 4x4 sheet of carbon fiber will have the same aerodynamic properties as a 4x4 sheet of iron.
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Old 11-20-2013, 07:06 PM   #95
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I say drive without a hood because you can. People do it all the time and I wouldn't hesitate to do it.
If you're planning on tying to the roof though try using towels or something as a spacer so that the hood is angles downward as to create downforce instead of upforce. Also, please don't bother with rope. Buy proper tiedowns with ratchets. Those will not come undone no matter what. Your rack will fly off before those come undone.
Yes downforce like someone said before but I'll probably stick to ropes as I have those handy. I bet you are right when you say tiedowns would be better but I think ropes will be safe enough. Thanks for the input.
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Old 11-21-2013, 02:02 PM   #96
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The roof racks are rated at 175lb. I'm almost certain, but you can google it to find out. For sure it's not 40lb....
Run a line to the front tow hook, and one to the rear tow hook if you have an extra one. A line through the car, either window or door opening, wouldn't hurt.

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Old 11-21-2013, 05:15 PM   #97
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Wait what?! Why are you saying it will have 500 pounds of upforce? That's nuts.
First, you do not know the angle in which the hood will be placed. And aerodynamic force is calculated by surface area, angle, and wind speed. Not weight of the object. A 4x4 sheet of carbon fiber will have the same aerodynamic properties as a 4x4 sheet of iron.
I am not an engineer, and I will leave that calculation to the expert. What I said was somewhere between 200 and 500........I have no idea exactly what it is BUT what I have experienced is that if the ropes stretches a bit and the hood starts catching the wind on the front, at 60 mph there will be tremendous upward FORCE on that hood, enough to rip the hood off the roof if the angle becomes too great and the ropes are not made to take that load. 200 pounds, I am guessing it will easily be with a slight angle. Based on carrying similar things on the roof, clothes line rope will most likely snap if there is any upward force. That is why I am suggesting nylon rope, or polyester ---need to look at the rating based on rope size.
Downward force will not be a problem, based on the racks taking 160 pounds or whatever.
PS--one may want to remove the hood grills so that the tie down ropes can go through that area.
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Old 11-21-2013, 10:20 PM   #98
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I read the first page and the last page of this thread and - somewhere in between people went from saying "no-prob" to "bungee your hood to your roof"

What the heck???? Well anyways:
Don't bungee ANYTHING. If you really must drive with your hood on, use ratchet straps to hold it to your roof for the drive back.
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Old 11-22-2013, 12:39 AM   #99
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to much to read through it all, but...

bumper in backseat, and hood on the roof (lay towels down where itll contact the roof, use ratched straps to tighten with the actual ratched part inside the car with you.) this way you'll have nothing to worry about on the way there.
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Old 11-22-2013, 12:58 AM   #100
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to much to read through it all, but...

bumper in backseat, and hood on the roof (lay towels down where itll contact the roof, use ratched straps to tighten with the actual ratched part inside the car with you.) this way you'll have nothing to worry about on the way there.
no way in hell the bumper is going in the backseat. it's wider that the actual car itself.
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