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With a UD pulley, typically more miles is better. Charging problems can occur at idle, which happens when you are stopped. Lots of miles typically means the car is moving and well into the charging range.
The other thing to think about with a UD pulley and stock idle speed is the A/C. On a hot day in heavy city traffic spent waiting for red lights to change, the A/C can be less than satisfying. Just like the charging issue, the more the car is moving the less you'll notice any difference from stock.
With a UD pulley, typically more miles is better. Charging problems can occur at idle, which happens when you are stopped. Lots of miles typically means the car is moving and well into the charging range.
The other thing to think about with a UD pulley and stock idle speed is the A/C. On a hot day in heavy city traffic spent waiting for red lights to change, the A/C can be less than satisfying. Just like the charging issue, the more the car is moving the less you'll notice any difference from stock.
The 10% UD pulley I installed has the stock size A/C pulley.
I'm unsure if the 25% can be purchase with a stock size A/C pulley? OP can call Byun Speed and they can tell you.
The 10% UD pulley I installed has the stock size A/C pulley.
I'm unsure if the 25% can be purchase with a stock size A/C pulley? OP can call Byun Speed and they can tell you.
I have a 25% and use the stock pulley. No issues to report.
The only concern I'd have is if you have any aftermarket electrical draws(ie stereo system) as you have an auto with a lower idle speed in gear than a manual.