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boom Offline
#1 Posted : Saturday, 8 December 2007 5:55:45 AM(UTC)
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just reading an old post by byron, what would the compression ratio be if i put 202 4cc dish pistons in? i don't know how to calculate the compression ratio if the pistons are sitting 1/8th down the bore at TDC any ideas?



If it doesn’t burn fossil fuels, it’s not a sport.
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#2 Posted : Monday, 10 December 2007 9:57:01 PM(UTC)
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If you are trying to lower the compression ratio of a 186 by using 202 pistons eg for turbo/blower application I imagine you'd want flat or dome top 202 pistons (if dome top actually exist?) and a 161/173 head. At a guess this would probably equate to abo
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HK1837 Offline
#3 Posted : Monday, 10 December 2007 9:57:01 PM(UTC)
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If you are trying to lower the compression ratio of a 186 by using 202 pistons eg for turbo/blower application I imagine youd want flat or dome top 202 pistons (if dome top actually exist?) and a 161/173 head. At a guess this would probably equate to abou
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If we all had the same (good) taste, who would buy all the Fords?
JBM Offline
#4 Posted : Monday, 10 December 2007 10:13:02 PM(UTC)
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The comp ratio is the swept voulme (bore x stroke) divided by the total combustion chamber volume.

ie: Bore x Stroke
-----------------------------------------------------
Bore Volume Above Piston + Piston Dish + Head Cha

You only have to be in front at the end of the race.
JBM Offline
#5 Posted : Monday, 10 December 2007 10:28:30 PM(UTC)
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quote:
Originally posted by Byron Rich
or dome top 202 pistons (if dome top actually exist?)

You only have to be in front at the end of the race.
boom Offline
#6 Posted : Monday, 10 December 2007 11:56:22 PM(UTC)
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pin height is the same. changed my mind. gonna use a 202 for the turbo idea.



If it doesn’t burn fossil fuels, it’s not a sport.
Dr Terry Offline
#7 Posted : Tuesday, 11 December 2007 1:13:46 AM(UTC)
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quote:
Originally posted by JBM
The comp ratio is the swept voulme (bore x stroke) divided by the total combustion chamber vol
If at first you don't succeed, just call it Version 1.0
basketcasebear Offline
#8 Posted : Tuesday, 11 December 2007 6:23:02 AM(UTC)
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Hey Doc, Terry
does this mean the air fuel is compressed to 1/8, of its original volume??
or 1/9,,etc etc? whatever the ratio is?
and if so, how does this relate to "bar", the term they use for air compressors, and their efficency??
cheers

ptpro
m
more than basketcase than a bear!
DOH!!!
Dr Terry Offline
#9 Posted : Tuesday, 11 December 2007 5:45:38 PM(UTC)
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quote:
Originally posted by fallingbear
Hey Doc, Terry
does this mean the air fuel is compressed to 1/8, of its original volu
If at first you don't succeed, just call it Version 1.0
basketcasebear Offline
#10 Posted : Tuesday, 11 December 2007 10:04:38 PM(UTC)
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Hey thanks doc.
another question>> a small model eg, aeroplane etc,,engine, can it still produce the same amount of compression?
and if so, would this mean if one had say ten 20cc engines, it would still equal the same as having 1 200cc engine, th
more than basketcase than a bear!
DOH!!!
Dr Terry Offline
#11 Posted : Tuesday, 11 December 2007 10:34:45 PM(UTC)
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Hi fb.

Youve asked 3 questions in one this time.

Yes, 10 x 20cc engines will have the same swept volume as 1 x 200cc engine. But compression figures will differ.

What many people confuse is the comparison between the compression ratio & cylinder
If at first you don't succeed, just call it Version 1.0
Dr Terry Offline
#12 Posted : Tuesday, 11 December 2007 10:34:45 PM(UTC)
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Hi fb.

You've asked 3 questions in one this time.

Yes, 10 x 20cc engines will have the same swept volume as 1 x 200cc engine. But compression figures will differ.

What many people confuse is the comparison between the compression ratio & cylinder
If at first you don't succeed, just call it Version 1.0
basketcasebear Offline
#13 Posted : Wednesday, 12 December 2007 6:07:04 AM(UTC)
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thanks doc!!!
i will have to think about it all for only a little while, to figure it out?? 2>3 weeks!!! but it is very helpful?
cheers

ptpro
madmax transit, 308t400 campervan
more than basketcase than a bear!
DOH!!!
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