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      04-02-2021, 12:59 PM   #181
tom @ eas
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Quote:
Originally Posted by astris View Post
Recently had rod bearings and new O2's installed. While I was at it, I switched from the 98mm pulley to the 96.5mm on my G1. According to ESS, I should have picked up .5-.7psi. However, I seem to have actually lost .5psi according to my P3 gauge with analog sensor t tapped in line to the bypass assembly. Gauge readings have been extremely consistent to date.

Previously - 98mm pulley, 91oct file, 92oct fuel. Consistently hit peak of 7psi ish over the 1200 miles I had it installed.

Currently - 96.5mm pulley, 91oct file, 92oct fuel. First drive (200 miles) peak boost maxed at 6.8psi. Second drive (50 miles) peak boost maxed at 6.6psi.

Conditions are not a factor either. All mileage above was roughly same elevation (close to sea level) same outside temps (all within maybe 10 degrees).

Not sure what would cause an immediate small drop in psi exactly when a new, smaller pulley was installed. It obviously can't be the pulley itself. Not sure where to start looking though. Thoughts?
Doesn't make sense, unless there's a small boost leak somewhere.
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Last edited by tom @ eas; 04-02-2021 at 01:35 PM..
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