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Discussion Starter · #1 ·
-I know that the boost level on each installation will differ for the same pulley ratios dependant on various factors like whether there is an intercooler fitted/intake temps etc. but was just wondering what the boost level difference was likely to be between the following:

stock 130 crank/62.5 nose
150 crank overlay/67.5

-I'm only running about 6-6.5psi at the moment with 130/62.5 & wish to know if it's worth me changing it to 150/67.5 (I don't want to risk 150/62.5 at the moment).
 

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Blue is the colour - not the mood
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I was getting near on 10 psi with my 1.8 with 150/67.5 pulley ratio, that was before I intercooled it and fitted the Adaptronic.
I only had a power card and JR timing controller at the time so really think I was chancing it at the time.

Oh just for the record I was still only getting about 10 psi with the 150/62.5 pulley ratio but that was after I intercooled it.

Michael
 

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Mine's a Beer
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The problem with the PSI figure is that it is more a measure of the restriction than the amount of air being moved

My 99 with 150/67.5 was about 10psi un-cooled but actually is 7.6 with a charge cooler and 7 when you add WI to that
 
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