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aardvarcus · 12-08-2014, 08:29 AM

Your sketch and write-up shows the trailer very close to the car, with the caveat that the maximum angle between the car and trailer is 45 degrees. I would want more maneuverability than that, the small wheelbase of your car is an advantage to trailer maneuverability, but you will limit yourself if impose this limitation on it.

Think about being in a full parking lot and having to pull out of a parking space with cars on either side of you and across the aisle in front of you, where you have to make a quick turn to the side to get into the parking lot isle. You have to keep going straight so that you don’t drag the trailer into the cars beside you, and then cut the wheel hard at the last minute to make the turn. You might be able to swing it with a small car with a small trailer, but in a truck with a trailer you would have a hard time getting out of there with a 45 degree limit.

An important part of trailer design is deciding the theoretical load it is designed to haul. Your trailer inside width is less than 48”, so it doesn’t look like you are trying to haul 4x8 sheet goods. I would want to design the trailer with the wheels inside the body work, but that would limit your width in between the wheels at the axle. If you were just hauling smaller boxes or items, that wouldn’t be that big of a deal though.

Also, your streamlining templates don’t look quite right to me. Attached are top and side views of AST-II overlays on your existing drawings.

Edit: I think the side overlay originally posted didn't align the ground planes correctly, I think it aligned the ground of the car with the under body of the template. Notice on the new drawing posted the template perfectly follows your car. Also on the top view drawing originally posted, it was following the greenhouse of the car, but based on the height of the trailer the new drawing fit the template to the bodywork on the sides of the car. Notice how perfectly your car fits the template from this view as well. If you are trying to reduce CD, I would try to follow the template as much as possible.

12-08-2014, 08:29 AM	#7 (permalink)
aardvarcus Master EcoModder Join Date: Apr 2012 Location: Evensville, TN Posts: 676 Deep Blue - '94 GMC Suburban K2500 SLE 90 day: 23.75 mpg (US) Griffin (T4R) - '99 Toyota 4Runner SR5 90 day: 25.43 mpg (US) Thanks: 237 Thanked 580 Times in 322 Posts	Your sketch and write-up shows the trailer very close to the car, with the caveat that the maximum angle between the car and trailer is 45 degrees. I would want more maneuverability than that, the small wheelbase of your car is an advantage to trailer maneuverability, but you will limit yourself if impose this limitation on it. Think about being in a full parking lot and having to pull out of a parking space with cars on either side of you and across the aisle in front of you, where you have to make a quick turn to the side to get into the parking lot isle. You have to keep going straight so that you don’t drag the trailer into the cars beside you, and then cut the wheel hard at the last minute to make the turn. You might be able to swing it with a small car with a small trailer, but in a truck with a trailer you would have a hard time getting out of there with a 45 degree limit. An important part of trailer design is deciding the theoretical load it is designed to haul. Your trailer inside width is less than 48”, so it doesn’t look like you are trying to haul 4x8 sheet goods. I would want to design the trailer with the wheels inside the body work, but that would limit your width in between the wheels at the axle. If you were just hauling smaller boxes or items, that wouldn’t be that big of a deal though. Also, your streamlining templates don’t look quite right to me. Attached are top and side views of AST-II overlays on your existing drawings. Edit: I think the side overlay originally posted didn't align the ground planes correctly, I think it aligned the ground of the car with the under body of the template. Notice on the new drawing posted the template perfectly follows your car. Also on the top view drawing originally posted, it was following the greenhouse of the car, but based on the height of the trailer the new drawing fit the template to the bodywork on the sides of the car. Notice how perfectly your car fits the template from this view as well. If you are trying to reduce CD, I would try to follow the template as much as possible. Attached Thumbnails Last edited by aardvarcus; 12-08-2014 at 08:35 AM..