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Old 10-31-2005, 08:36 PM
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Default compression question

about what should the compression be on a 509 w/ a 250 blower?,
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Old 10-31-2005, 08:37 PM
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Default Re: compression question

My 509's Are 185
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Old 10-31-2005, 08:40 PM
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Default Re: compression question

are they blown
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Old 10-31-2005, 08:54 PM
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Default Re: compression question

More info required like compression ratio and cam specs. Even then unless someone has your exact combo it will only be educated guesses. What are your compression numbers reading?

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Old 10-31-2005, 11:15 PM
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Default Re: compression question

like vette said, need cam specs and combustion chamber cc and assuming your 509 is a 4.5 bore to give you an educated guess.
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Old 10-31-2005, 11:36 PM
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Default Re: compression question

First thing you want is less than 10% difference between cylinders. Blower motors can be all over the place because of cranking speeds during the test. A better test is a leakdown of each cylinder-once again less than 10% is good. Also if it leaks you can get an idea of where the problem is-better than by checking compression.
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Old 11-01-2005, 07:53 AM
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Default Re: compression question

insptech is on the money the general rule of thumb is all cyclinders should be within 10% of each other a cyclinder needs roughly 100ftlbs to fire newer motors are around 150 - 185 give or take after the rings seat.
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