Lakester WheelBase & Track

[oj]

Is there a better wheelbase and track width?  Should front and rear wheels be in same track?  Any advantage in asymetrical wheel base, like one side ahead of the other or just one tire staggered?  Should the front tires be leading the sheetmetal (like the nose of a lakester), be equal to it or be behind it?  Any other tire placement questions or issues I should be asking?

[dw230]

Why would you want to place one side ahead of the other? We are not bracket racing here.

DW

[bearingburner]

If the tread with is the same front and back then you only have to make one hole in the wind. You talk about staggering the wheels. I hope your not trying to go around corners with a lakester. As for wheelbase my feelings is longer is better after watching short wheelbase dragsters run 50 years ago.

[SPARKY]

if you are going to fair the axles then it helps to have the inside of the frt and rear tires be the same!!

[Stainless1]

Our lakester is 45.25 front, 31 rear, 140 wheelbase.  Could not tell you if that is good, bad or indifferent but it is the configuration that a friend of ours, Lynn Yakel, suggested.  Since he was the designer for the original streamliner when we converted to lakester, Ben Jordan called him to get his best guess for aero. 
Seems to work for us 

[jacksoni]

Our lakester is 45.25 front, 31 rear, 140 wheelbase.  Could not tell you if that is good, bad or indifferent but it is the configuration that a friend of ours, Lynn Yakel, suggested.  Since he was the designer for the original streamliner when we converted to lakester, Ben Jordan called him to get his best guess for aero. 
Seems to work for us 

Didn't Lynn Yakel design or consult or something on the Larsen&Cummins #115 Liner? What a beautiful and successful car!

[Sumner]

If the tread with is the same front and back then you only have to make one hole in the wind.

I think that might have some merit on a very short wheelbase car but with the length of the wheelbase of most lakesters I feel the air fills back in behind the front tire and the rear then has to pass through it.

On the spreadsheet I have that helps to calculate the HP needed to run a certain speed with a lakester ....

http://purplesagetradingpost.com/sumner/bvillecar/bville-spreadsheet-index.html#HP needed for A Lakester

... I have inputs for front and rear tire heights and widths and Cd's,

Sumner

[kiwi belly tank]

Yeah, I agree with Sumner plus the path of the air flow is relevant to the shape of the body.
  Sid.

[oj]

How about the forward placement of the front tires, I see some cars with an extended front and some tanks the tires are ahead of the body.  Any thoughts on this?
It looks like my tires will be ahead of the nose, the front axle about 12" behind the tank nose. 

[Rex Schimmer]

Regarding the track width of a lakester, I am of the line of thinking that the farther away from the body the better. With the tire mounted close to the body the interaction of the air going over the body and the disturbed air around the spinning wheel/tire completely disrupts any potential for attached air flow after the tire. If you happen to look at a lakester that has its' rear wheels close to the body, and there are several that have run damn fast, you can many times see a streak of salt on the body just ahead of the tire. I believe  that this is the result of the air turbulence caused by the tire preventing attached air flow from going past the tire and along the body behind the tire. You have effectively made the back of the car into a non aero surface. The data that was provided by Woody regarding lakester aero shows that the tires are the single largest aero load, next are the axles. Stream lining the axles is pretty straight forward and easy and effective so I  like a wide wheel base, streamlined axles and close attention to wheel size and aero attachments. (Check out Sparky's front wheels for some great thinking about improved wheel aero!)

Rex

[Sumner]

Regarding the track width of a lakester, I am of the line of thinking that the farther away from the body the better. With the tire mounted close to the body the interaction of the air going over the body and the disturbed air around the spinning wheel/tire completely disrupts any potential for attached air flow after the tire. .....Rex

I agree and the rendering that you did above of what my car, if ever finished, might look like illustrates one possible view of what you are talking about.  The side pods will be shaped like an inverted foil at the leading edge and trailing edge. 



The pods are 6 inches tall and contain the axles and room for a small amount of suspension travel and storage for cooling water tanks between the axles on both sides,

There is more on my design thoughts here  (take them with a grain of salt  )...

http://purplesagetradingpost.com/sumner/bvillecar/construction%20page-1.html 

and body here....

http://purplesagetradingpost.com/sumner/bvillecar-2/construction%20page-88.html

Sumner

[oj]

Regarding the track width of a lakester, I am of the line of thinking that the farther away from the body the better. With the tire mounted close to the body the interaction of the air going over the body and the disturbed air around the spinning wheel/tire completely disrupts any potential for attached air flow after the tire. .....Rex

I agree and the rendering that you did above of what my car, if ever finished, might look like illustrates one possible view of what you are talking about.  The side pods will be shaped like an inverted foil at the leading edge and trailing edge. 



The pods are 6 inches tall and contain the axles and room for a small amount of suspension travel and storage for cooling water tanks between the axles on both sides,

There is more on my design thoughts here  (take them with a grain of salt  )...

http://purplesagetradingpost.com/sumner/bvillecar/construction%20page-1.html 

and body here....

http://purplesagetradingpost.com/sumner/bvillecar-2/construction%20page-88.html

Sumner

Thanks, I'll read thru the links with great interest.  I have no idea what an 'inverted foil' is at the moment but I suspect its' one of the things I'll have to earn about.

[bearingburner]

Rex are you talking of belly tank bodies, rear engine dragster type bodies or something like Sumner drew?

[Sumner]

Rex are you talking of belly tank bodies, rear engine dragster type bodies or something like Sumner drew?

The drawing above was done by Rex....

Sumner

[Rex Schimmer]

bearingburner,
I would mainly consider "tank" style bodies as they are inherently aerodynamic, flat sided dragster style bodies, many of which have either no body work behind the rear wheels or have a tail section that is to short and the transition from the main body to the tail section is an abrupt transition will typically have the rear wheels close to the body and it probably does not make much difference as the wheel/tire completely disrupt the air flow anyway. Yes there are some flat sided cars that have gone very fast, that is usually because they have really strong engines and I also know that the very successful J,I,and K class lakester, the Bockscar ,is flat sided and the rear wheels are fairly close to the body but the success of this car probably shows what the minimum wheel/tire clearance should be to have good air flow over their very aero rear body shape. It also shows that Stainless builds some really killer motors!

rex