Open or closed partial boat tail

[aerohead]

Originally Posted by paintme205

Thanks Aerohead for the input. I think the weather is crap now to compare anything unless it's same day and same direction of travel.

Yesterday I was annoyed at the MPG and didn't have time to test A-B-A for 200 miles. So I decided to try a top speed test.

Previously the car mainted 94 MPG on level ground and around 99 max. Yesterday It held 100 to 101 on level ground and 106 with a nice hill to get a running start. So I'm pretty sure aerodynamics must be a little better.

The bad part is I think I blew a headgasket....

I found Hucho's original top speed research from 1976 and it reported a 11.59% top speed increase for a 30% drag reduction for a car with radial tires.
If,say.the top speed went from 94 mph,to 101 mph,then from Hucho's relationship it would suggest a 19.26% drag reduction necessary to get that speed.
Sad news about the head gasket.It's a days job if you have the parts on hand.Watch your back.I did my Honda a year ago and I'm still sore from it.