If they are swept, then you probably can't easily dimension them. Sorry, just the way life is. In the old days, such shapes would be dimensioned at certain points along the length, usually evenly spaced. In my line of work, plastic injection molded parts, we let the solid model drive the shape and just put in a few inspection dimensions. I cheat and do things like placing a very short horizontal line tangent to the curved edge near the highest point on the drawing, then adding a vertical dimension to it to show the height.
Jerry's trick actually works pretty well - you can sketch lots of entities on the drawing to help you dimension what you need - including arcs that approximate segments of splines and points at intersecting lines. These sketched entities can be put on the hidden layer in the drawing so they are not seen...
You can try your luck with things like Fully Define Sketch (if this is a SolidWorks model with sketches). Info on that can be found below:
Overall, I'm not sure this will give you 'exactly' what you want. But it's something to look at in my opinion.
Hope this helps!
The person who did this in solidworks used images with the top, front/side and right planes. Then he drew the lines over the images and then surface swept them. I used construction lines and zoomed in very close and checked the length and height of the car and its according to scale. I wonder if I start from scratch and when I have the lines then use weldments/structural member to follow the paths if solidworks will then give me a BOM for the steel? I basicly need the radius of the 4 main pipes in the drawing. Problem is that there is 2 radius in the top pipes. Thanks for the help guys.