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  #1  
Old 27-11-2006, 14:50
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i ran 32psi with the stock gasket.
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fj20/et a replacement for displacement
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  #2  
Old 27-11-2006, 18:48
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Thicker gasket would upset the cam timing and also harm off boost performance and fuel economy imho
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  #3  
Old 28-11-2006, 09:40
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The cam would be advanced by less than a degree with even a 2mm gasket, so its not anything significant.

The off boost power would be reduced.
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Old 28-11-2006, 23:35
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All of the above plus the fact that the boost depends on a fine balance between the comprssion ratio and the volume of air been induced into the cylinders. Yes the engine will take in more air, but what you gain you'll lose automatically becase the compression ratio will be far less. Sorry mate but you'll acheive nothing.
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Old 28-11-2006, 23:43
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surely the increase in boost pressure that he's lookin to gain from doing this will over compensate the loss of compression!
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  #6  
Old 29-11-2006, 00:50
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Quote:
Originally Posted by Beany-s12
surely the increase in boost pressure that he's lookin to gain from doing this will over compensate the loss of compression!

but the ET is already a low compression engine, at 8:1 it's lower than a lot of turbo engines of the same era, newer turbo engines seem to be running a lot higher CR. the Audi/VW 1.8T is 9.5:1 for instance. IMO you don't need to go lower than 8:1.

The engine I'm building will have re-worked combustion chambers but I will skim the head to compensate
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  #7  
Old 29-11-2006, 08:52
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i thought the ET was 8.5:1
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