Just read the thread from the link redneck44 posted.
They say 4-5mpg
Not sure on cruising speed - I imagine you would need to budget for 500lbs of dynamat in a futile sound proofing attempt to prevent your ears from bleeding on the highway!
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.