While I will bow to the knowledge and experience of owners like Tom I stick to my original response. 10:1 compression is too high for big boosting, regardless if you use a positive displacement blower or use a centrifugal type.
OTs point about the centrifugal type being less sensitive to low RPM detonation is a given, but this chap is using a Lysholm.
For long term use and engine safety you will be more secure with a 4-6 lbs pulley.
If you use a 7-10lbs pulley it won't blow up a good engine. Not straight away anyway.
Anything over 10 lbs on stock internals is looking for trouble.
For the overall cost involved spend 500 bucks on a good water injection setup and at least gain the horsepower from the pounds you are boosting.
Joe
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