Shoestring from 1949 design

[First time Juke]

I found this:

http://airbum.com/pireps/PirepShoestring.html

I was wondering how much of the speed increase in F1:s is due to engine and prop and how much due to the aerodynamics of the AC ?

[First time Juke]

Re: Shoestring from 1949 design

To my great..GREAT surprise I see that Shoestring #16 actually qualified in 1980 faster than AR-6 Endeavour finished in Gold Race 2008.

http://www.airrace.com/New%20speedrecords.htm

How is this possible ?

John Parker can you explain what happened to Shoestring # 16 in the Gold Final in 1980 ? Congratulations of the consecutive wins by the way !
Also Wild Turkey # 3 was faster than AR-6 Endevour 2008...was the course faster back then ?