Long Term Effects Of Pullies?

michaelgta said:

I want to add pullies to my 2005 GT.
I have had them before on my 2000 and 2003 GT. The deal is I was not keeping them and did not care about any long term effects. Will pullies cause any long term effects to my engine? I know the water pump pulley is slowed down so would'nt that effect how well your engine cools? Also why is there only two pullies now as opposed to three?

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michaelgta said:

one last question...Do you have to get a tune for the pullies? I have not recieved a good answer on this yet.

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Power Surge said:

A proper underderive set usually comes with a smaller lower pulley to slow the accessories down and therfore less load, but also a larger water pump and alternator pulley to speed those two items back up to normal speed, so you don't have a loss of cooling or charging.

The Steeda kit just shows the lower and the water pump. Maybe the alternator on the 05 works well enough to not have a charging loss with a little lower rpms. I know that it's a PITA to get the alt pulley off and requires a special tool on the 05s, so maybe they didn't want people to have to deal with that.

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delurker said:

A larger pulley on an accessory will actually slow it down further, since it's driven off the belt.

The 05 alternator has a clutch like the a/c, that's why you don't get an alternator pulley.

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michaelgta said:

so what you two have agreed to is that because the water pump is moving faster you get better cooling? But doesnt that still make your engine work just the same as being stock? I am confused....a little help here if you would?

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Power Surge said:

Oops, you are correct. You get a SMALLER water pump and alternator pulley with the underdrive kits .

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delurker said:

Actually, no. You get a larger water pump pulley, so you can use the stock belt. The crank pulley is a little bit smaller than stock, and the water pump pulley is a little bit larger than stock - togther, they slow down your alternator and a/c a little, and your water pump a little more.

The penalty you pay for the 8-10 hp you gain is that you don't get quite as much a/c, charging, or water movement at idle, but the effect isn't supposed to be enough that you'll notice - as if there's a bit more than you need built into the stock setup.

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