Quote:
Originally Posted by 3-Wheeler
Maybe not as clean and consistent as doing all the changes in one day, but adding under body panels AND the tail extension to the car would take multiple hours to accomplish just one change.
Practicality speaks!!
Jim.
|
I certainly agree about practicality!!! It is a powerful constraint.
I did some experimental driving today on I64 east to Williamsburg. I was interested in the lean burn performance at speed. This route has long gentle hills, pretty much one after another, for most of the distance. I targeted two cruising speeds, 55mph +/-2, and 60 mph +/-2. I was able to pretty much hold his over the entire distances. I think that level of speed control is adequate, since the errors will cancel. I noted that on my car I was able to stay in lean burn at both speeds, with an occasional downshift to 4th, clicking right back to lean burn. On the boattail testing, I think 60 mph gets the nod because we are trying to improve the high cruise performance - if I'm not mistaken.
I think I am going to search for a good interstate section of about 10 miles one way as a test course. (From memory, I believe that I95 south of Richmond is superior to I64 east, but I have to have a look.) For most areas that I have seen the interstate is near optimum for testing at this speed. The occasional truck that approaches from the rear can be warned with a couple of quick flashes, as can any dense traffic approaching from the rear. There seems to never be any forward obstruction at this speed
It seems to me that on something as complicated as a boattail testing, it almost has to be tested and baselined on different days. As you alluded, that will mean that one must observe temperature and barometric pretty closely and duplicate conditions as closely as possible, or be able to make some adjustments as suggested. Of course, tuft testing can be done on most any day unless it is raining. (Any substantial testing in one day usually involves changes in temp anyway, as you noted.)