need some (alot) help with bbc

Old 08-30-2009, 03:24 PM
  #1  
sxfreak2002
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Default need some (alot) help with bbc

i have been chasing my tail all year and nothing has worked . so im asking for any suggestions. i have a 4link dragster with a 572bbc and im shifting at 7400 and after the shift im dropping off to about 6200 and crossing the finishline at 6000. my sixty foot times have dropped.from 115 to 128. and my 1/8 mile has dropped to a 540. at 128.was running 770s at 176. 1/4 and 490s 1/8. last year and the only thing i have changed is the rods went to grp .car started off at 8.00 at 168. i have changed everything i can think of. checked all the wires,new plugs wires cap rotor coil . changed the converter.new tires the motor was freshened at the first of the year.did a leakdown ,compression check checked the springs.the cam .i have a retard box on it and it is grounded and a zero chip so not sure if it can still cause a problem.i am lost what else can there be the motor seems to run fine .holding9 pounds fuel at 6200 on the converter. changed carbs. if anyone has a clue what else it could be please let me know im thinking that it may be the tranny. got it going to the shop tomorow. but is there anything in a glide that can put that much load on the motor?
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Old 08-30-2009, 05:55 PM
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chrisr
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So after shifting and falling off to 6200 you lose 200rpm by the time you reach the line?
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Old 08-31-2009, 06:45 AM
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sxfreak2002
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yes it is loosing rpm. and it is real slow to get to the shift point. i had it on time shift and it was shifting at 6600. so i put it on rpm to see if it would help.i can bring it up on the converter 6200 and it seems fine.but with a load nothing.
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Old 08-31-2009, 07:32 AM
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bbchevy
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Have you Cut the Oil Filter apart,or if using a System 1 type Filter?Checked it for METAL?
Later
G 8)
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Old 08-31-2009, 12:03 PM
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johnracer
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If the band was adjusted too tight it might do that. Low gear would work fine, but would be dragging the band in high. Maybe a stuck servo or broken servo spring could cause something similar........
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Old 08-31-2009, 07:48 PM
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sxfreak2002
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just pulled the trany apart and there is nothing wrong with it. had some shavings in it. we pulled the converter apart (bolt together) and it was fine. the first one i had in it must be the shavings.msd tells me there is nothing that im having my problems with can be related to the msd.maybe a fuel issue. maybe the cam timing moved? man i am lost.
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Old 08-31-2009, 07:50 PM
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hows the rear end is it free spining.
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Old 08-31-2009, 08:01 PM
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sxfreak2002
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yeah it seams to spin with out drag. rotors arn't dragging on the pads. everytime i get to the finishline . i shift to neurtral and motor is dead.im gonna check to make sure the regulator. screens arnt pluged up.i have -10 to the reg and -8 to the bowls.a holley 500 fuel pump .aeromotive reg.everything i have electric wise is run off the power switch could it be that the power switch is not getting good contact and loosing power to all electronics?like i said it is driving me crazy. only my second year at the drag racing bit and its been a tough year.
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Old 08-31-2009, 08:49 PM
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chrisr
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I had the same thing happen to me once, it turned out that my shifter was not adjusted just right, when I shifted to second it was not engaging all the way and letting the valve body bypass fluid. Under hard excelleration it would do the same as yours. If I was in the pits and went to second it would feel like I was applying the brakes. I was skeptical when my tranny gut told me that what is was but sure enough I adjusted it just a little and it worked fine. May not be what yours is but worth checking.
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Old 09-01-2009, 08:10 AM
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TheYellaBrick
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Originally Posted by chrisr
I had the same thing happen to me once, it turned out that my shifter was not adjusted just right, when I shifted to second it was not engaging all the way and letting the valve body bypass fluid. Under hard excelleration it would do the same as yours. If I was in the pits and went to second it would feel like I was applying the brakes. I was skeptical when my tranny gut told me that what is was but sure enough I adjusted it just a little and it worked fine. May not be what yours is but worth checking.
Basically it was in 2 gears at the same time causing a bind-up situation
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