Underdrive Pulleys?
Got my car back with the full Ultra SS pulley set installed. I can feel a difference. I had my timing advanced 2 degrees down low. The throttle response is quicker and definately noticeable. Sammy is a cool cat..
I was browsing the internet and saw the UR Pulley Kit. I won't by the HP increase it claims, but I will believe the smoother/faster throttle response. And so, I believe I may add this to the list of "to be done".
Therefore, how hard are they to install. I'd imagine the hardest part would be dealing with the belts.
Therefore, how hard are they to install. I'd imagine the hardest part would be dealing with the belts.
Here is the deal...
The crank pulley is the one that provides most of the gains. The other 2 accessory ones are basically for looks. To break this info down even further, approx. 80% of the gains from a pulley are due to the lighter weight of it; i.e. less rotational mass. The stock pulley weighs around 5 pounds give or take and my CNR lightweight(not underdrive) pulley weighs around 2-3 pounds. The other 20% is from the actual underdriving of it.
And you DO NOT want to run a underdrive pulley with a SC as it will lower the amount of boost you see. Logically, if you are underdriving the accessories, then you will be underdriving the supercharger as well!
I do not have actual proof of all of this as I have followed everyone elses advice on here, but it is all info I have gained over the past 2.5 years I have been on this site.
The crank pulley is the one that provides most of the gains. The other 2 accessory ones are basically for looks. To break this info down even further, approx. 80% of the gains from a pulley are due to the lighter weight of it; i.e. less rotational mass. The stock pulley weighs around 5 pounds give or take and my CNR lightweight(not underdrive) pulley weighs around 2-3 pounds. The other 20% is from the actual underdriving of it.
And you DO NOT want to run a underdrive pulley with a SC as it will lower the amount of boost you see. Logically, if you are underdriving the accessories, then you will be underdriving the supercharger as well!
I do not have actual proof of all of this as I have followed everyone elses advice on here, but it is all info I have gained over the past 2.5 years I have been on this site.
Last edited by zachcrosen; Jun 22, 2006 at 08:45 AM.
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