234" Mike Bos slip joint dragster...pulling the wheels

Old 06-01-2010, 10:43 PM
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dparker
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Default 234" Mike Bos slip joint dragster...pulling the wheels

Our problem is we have a 234" Mike Bos dragster with a SBC it runs 8.50s with 1.18 60ft...the car is pulling the wheels out of the beams causing the car to have inconsistant reaction times and ETs. We're up to 75lbs on the nose. We're running a 6000 stall 8" converter, and 5lbs of air in the rear tires. The car will run a 8.62 et, with a 1.18 60ft and a .498 light then run a 8.59 et, with a 1.20 60ft and a .520 light. We added a 42lb battery midchassis, it caused the car to chirp the tires down track. No redlights but took the consistancy away from the car as well.
Whats the best way to keep from pulling the wheels out of the beams. I don't like adding anymore weight up front.
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Old 06-02-2010, 06:30 AM
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johnracer
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I'd try a little more tire pressure. If it spins a touch, it may not pull the front. I know on my FED, it would pull the front out of the beams if it tried to dead hook, and would bounce & chirp for the rest of the run....
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Old 06-02-2010, 07:03 AM
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hammertime
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Default Re: 234" Mike Bos slip joint dragster...pulling the whe

Originally Posted by dparker
Our problem is we have a 234" Mike Bos dragster with a SBC it runs 8.50s with 1.18 60ft...the car is pulling the wheels out of the beams causing the car to have inconsistant reaction times and ETs. We're up to 75lbs on the nose. We're running a 6000 stall 8" converter, and 5lbs of air in the rear tires. The car will run a 8.62 et, with a 1.18 60ft and a .498 light then run a 8.59 et, with a 1.20 60ft and a .520 light. We added a 42lb battery midchassis, it caused the car to chirp the tires down track. No redlights but took the consistancy away from the car as well.
Whats the best way to keep from pulling the wheels out of the beams. I don't like adding anymore weight up front.
More weight ....

How red is it going ? When a car pulls the tires out of the beam its not general only a little red normally 25-45 red. 100 lbs would be next, chip it down on the hit, loosing the converter up.

and nice to see ya posting
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Old 06-02-2010, 01:14 PM
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dparker
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The last redlight was .488, or -.012..the other lights were .510 to .520.
We added 42lb battery in midchassis. figuring that would add approx. 30 more lb to the nose. But it seem to upset how the chassis worked. We have 73lb in the nose right now. Kinda running out of room in the nose. Mike Bos says to add tire pressure allowing the tires to spin approx. 1 revolution and the car will run consistant and not pull the front wheels. It just goes against everything in my head to make a car slip when your trying to run on the money...
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Old 06-02-2010, 01:21 PM
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shawnp
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I am with you on the tire spin but BOS has been doing it a long time. Sometimes lowering the launch has the reverse effect depending on the converter RPM and how hard it may flash the converter. I would recommend a very soft hit converter that is loose for the combo. That will help some.
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Old 06-02-2010, 02:03 PM
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hammertime
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what tire and what air pressure you running ?
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Old 06-02-2010, 02:24 PM
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dparker
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Goodyear 15x14.5x33 #2070. And 5lb of air...4200rpm chip at lauch..
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Old 06-02-2010, 02:33 PM
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johnracer
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I'm with you on it going against everything in your head, but I bet it'll be more consistent, 60' and et quicker with a little spin. Having a suspension makes the "dead hook" concept work.
Weight in the nose will help it spin, as will more power and higher tire pressure. I'm sure some converter tweeks will help too, but I'd still try more tire pressure......it's free.
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Old 06-02-2010, 02:55 PM
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dparker
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I guess next race we'll try the tire pressure..what so yall think about a 1 wheel wheelie bar?
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Old 06-04-2010, 06:40 AM
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hammertime
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Originally Posted by dparker
I guess next race we'll try the tire pressure..what so yall think about a 1 wheel wheelie bar?
Wheelie bar shouldnt be needed on a car slower then 7.00 without nitrous
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