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 Post subject: Wheelie Bar Height
 Post Posted: Thu Jan 01, 2009 1:28 pm 
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I tried a search but didnt really find what I was looking for.
What height should the wheel on my wheelie bar be at just prior to launch? Yes I have a single wheel. I dont remember exactly but I think mine is at something like 8 inches, I believe that is pretty high. I am looking at some modifications that should cause me to launch harder and I want to make certain the wheelstands are contolled.
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 Post Posted: Thu Jan 01, 2009 1:32 pm 
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Dennis, mine are 6" measured at the center of the wheel axle...

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 Post Posted: Thu Jan 01, 2009 3:06 pm 
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I think Sam runs a single wheel on his altered so he could give you some ideas on this also.

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 Post Posted: Sun Jan 04, 2009 4:57 pm 
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I run a single on mine. I launch at 3K without lifting the fronts and still 60ft about 1.19. All depends on how much of a tendancy the car has of getting up onto it. I'd say 8in is too high but again depends on the length of the bar. If you wanna run pulling the wheels up, I'd say a singles not really what you want and you'd be better off running twin.  Hit a rigid single too hard and it'll unload the rears  on a hardtail car.

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 Post Posted: Sun Jan 04, 2009 5:51 pm 
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Dennis,

I'd say 8 inches is way higher than you need. is the car suspended or rigid?

in my experience and from what I've been told set the wheel so you can slide you foot under is a good starting point, that will vary as you change your tire pressures and how hot they are. I slide my foot under so that the wheel is just before my ankle so I'd guess at about 2 inches.

I use the same on the suspended altered and on the rigid digger. I've never run a dual wheel bar so can't comment on them..

single wheel bars do tend to be longer so the initial setting can be lower (hint dont set them low as that and try to get it off the trailer).

if you set them high and hit it hard it will tend to try and push the front down to quickly which normally results in the front coming up again. I've had the altered up on the bar when I have shifted which does tend to unsettle it a bit.

Single or dual is a personal choice but the only class that seems to run dual's is prostock but theres lots of adjustment on the line, every other class seems happy with singles, as to unloading the tires I reckon you'd have to have some short bars set high off the ground and hit them really hard.

from setting up wheelie bars on other cars the dual wheel ones need more attention as they can steer you if not set correctly.

another thing to consider is how rigid they are, mine flex a fair bit as they are 80 inches long. mind you the first time I drove the digger the wheel was set at about 3 inches and was on the floor going into stage (tire screw up) and the front came up about 12-15 inches when I launched and that bar is only about 30 inches long effective length..

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 Post Posted: Sun Jan 04, 2009 6:33 pm 
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I have a single wheelie bar. Not sure how long it is but I know it is over 72" long. I have always thought it was too high. I launch at 5000. As I am finding more power the front end is coming up some and I expect it to get higher. I will be reworking or replacing my wheelie bar. I am going to have to figure a way to easily disconnect for loading in the trailer. In current configuration it's pain in the arse. I have to crawl under the car and the pins are in very tight spots.
Dennis

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 Post Posted: Sun Jan 04, 2009 8:00 pm 
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My buddies dragster is solid and it has a single wheel wheelie bar.
He always says it is about right when you can stick your foot under the wheel and can't go any further than your shoe laces. (my way of explaining it). His does just fine.

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 Post Posted: Fri Jan 09, 2009 6:27 am 
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oldtimer wrote:
I have a single wheelie bar. Not sure how long it is but I know it is over 72" long. I have always thought it was too high. I launch at 5000. As I am finding more power the front end is coming up some and I expect it to get higher. I will be reworking or replacing my wheelie bar. I am going to have to figure a way to easily disconnect for loading in the trailer. In current configuration it's pain in the arse. I have to crawl under the car and the pins are in very tight spots.
Dennis


mine has the lower single tube as a slipjoint so there is room to flex within it's make up. Sams right about shorter bars, my old slingshot would pull 2ft wheeldstands without the bar. The bar we made was too ridged and short, it would unload the rears and cause the front to come down heavy. 2in sounds about right but you still might find it bottoms out arund the pits unless they're smooth.

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 Post subject:
 Post Posted: Sun Feb 08, 2009 1:45 pm 
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While out working on the Fiat today and contemplating modifications I realized I could put a floor jack under the front and find out how high my wheelie bar would allow the front to travel. After jacking until the the wheelie wheel just touches the measurement is approximately 13 inches at the bottom of the front tire. Not as bad as I expected. Not as good as I want.

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 Post subject:
 Post Posted: Tue Feb 10, 2009 2:19 am 
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dennis,

is that a rear suspension car ?? if so that 13 will grow a lot with suspension compression, also add another couple of inches or so at the front for the flex in the bar..

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 Post subject:
 Post Posted: Tue Feb 10, 2009 6:30 am 
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Its a Hardtail. I would expect a bit more height with flexing in the wheelie bar but not too much. I would rather keep the front end down and move forward.

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 Post subject:
 Post Posted: Sat Feb 14, 2009 8:43 am 
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oldtimer wrote:
I would rather keep the front end down and move forward.

EXACTLY!! Any loading of the wheelie bar means less loading of the driving wheels.

How far are you from Greenfield? Do you run at Cordova, Omaha, or the eighth mile down in Missouri?

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 Post subject:
 Post Posted: Sat Feb 14, 2009 5:45 pm 
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Cordova is about 2 hrs from home. I spend my time at Tri State raceway near Earlville. Its only about an hour from home. I'm close to Cedar Rapids.

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 Post subject:
 Post Posted: Sat Feb 14, 2009 8:07 pm 
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oldtimer wrote:
Cordova is about 2 hrs from home. I spend my time at Tri State raceway near Earlville. Its only about an hour from home. I'm close to Cedar Rapids.

I ran at Cordova in the mid fifties. At that time, Arnie Beswick was running a Dodge D501.
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 Post Posted: Sun Feb 15, 2009 8:18 am 
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Mid fifties put me in elementary school. I had no exposure to drag racing until probably 1965 or so. Arnie was a legend around here. I have seen him race many times. I hope to get to Cordova to race this summer. I wont race the World Series but probably will attend.

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