The real data I have is from testing known area and weight
and power( 2 different engines with 3 different power
levels) and comparing the speed both at Bonneville and in
Australia. When you plug the numbers in to the appropriate
equations it comes up .5 on the Cd. All the speeds are
within 1 or 2 mph of the calculated. So I would have to say
for the 1 car tested this comes out to .5 , which just
happens to be pretty typical of the #'s I have seen
published for other open wheeled cars( got those from a pal
that did aero work for winning Indy cars). The math I got
from S.F. Hoerner.... His work is a little dated but I
suspect physics has not changed too much in this area of sub
sonic work. The 300 hp was from the test engine in the test
car. It fit your car with a .2 cd with a .28 obviously you
are making more power than that. It was for illustration
only though.
Racing yup that is what it is all about!
We all want to go more than 'Fairly fast on a sunny day'
LOL............
Dave Dahlgren
Rick Byrnes wrote:
>
> Who said 300 HP. I didn't hear or read that. Nor did I say that.
> Who said anything about 220 MPH? Not me? Since we racers are the most
> optimistic lot in the world, I expect to go lots faster than 220. Thats
> only fairly fast :=D
> Horsepower?
> I never said 300 HP.
> More than 300 for the N/A and lots more than 600 for the blown motor. At
> altitude.
> .28 Cd on the Merk.
>
> Do you have specific datas that indicate a .5 Cd on a lakester?
> If so can/will you please share it with the rest of the group? With a lack
> of real data, how do you arrive at a value of .5?
>
> But lets not quibble. I'm gonna go racing.
>
> Rick Byrnes
> We have enough youth...........How about a fountain of smart
> www.rbmotorsports.com
>
> ----- Original Message -----
> From: "Dave Dahlgren" <ddahlgren@snet.net>
> To: "Rick Byrnes" <rick@rbmotorsports.com>
> Cc: "Keith Turk" <kturk@ala.net>; <land-speed@autox.team.net>
> Sent: Thursday, January 18, 2001 12:59 PM
> Subject: Re: Rick's car
>
> > If you mean me, finally someone to race with... I am up for
> > it! But wait till you run the #'s with the CD of a
> > lakester... The difference will scare you. the 7.5 sq ft
> > lakester with a cd of .5 will go 205 with 300 hp sea level
> > corrected engine. My #'s say in a 21 ft car with a .2 cd
> > will go 199....
> > So i would not think you are going to go 220 with 9.5 sq ft
> > and 300 hp...in a lakester.. But hey we will see. How much
> > power does the engine make?
> > Dave Dahlgren
> >
> > Rick Byrnes wrote:
> > >
> > > Gee, I was kinda planning on zapping that ol chebby truck out.
> > > The Girlie camero is sort of ok though, It does go fairly fast.
> > >
> > > I will post more photos soon, including the new ride.....gotta make sure
> its
> > > mine first. My check has not cleared yet........but it will.
> > >
> > > Now, consider if my Merk went 174 with the N/A motor and it's 21 ft sq.
> and
> > > the new deal is 9.7 ft sq, how fast will it go? Do the same comparison
> with
> > > Turbo motor. I plan on having a bunch of fun in the next few years.
> > > Gonna give Dave some numbers to shoot for.....
> > >
> > > Rick Byrnes
> > > We have enough youth...........How about a fountain of smart
> > > www.rbmotorsports.com
|