UD Pulley
Supporting Vendor
Joined: Nov 2001
Posts: 410
Likes: 0
On my C5 with head/cam ect and yes UD pulley, 900rpm idle, the station attendant said it was the cleanest running car he ever tested w/sniffer.
Understand that the UD pulley can come with an OD pulley for the alternator so no added idle speed is needed ( I have installed them for cars with the stock idle and no OD alternator pulley without issue). Why are you so insistant on finding something not right? Sometimes in life you win.
Its a gift mod.
One more fact. When you do this mod it is usually in addition to a cam swap and no cam that makes any real change in power can use the stock idle rpm. Its a tech section and people come here to discuss mods and ultimately do them. The ones that stand the test of time and 1000's of installs are worth doing and I dont know anyone that skipped this mod when doing a cam. I see no one complaining about not passing emissions, voltage, current, ect. One more thing. When you get an emissions test done, it isnt at idle rpm.
I have never seen a single person remove one for it having a downside. If you had a stock idle, automaic trans, and had dimming due to huge stereo amps being drawn, you get an OD pulley for the alternator and its done.
Understand that the UD pulley can come with an OD pulley for the alternator so no added idle speed is needed ( I have installed them for cars with the stock idle and no OD alternator pulley without issue). Why are you so insistant on finding something not right? Sometimes in life you win.
Its a gift mod.
One more fact. When you do this mod it is usually in addition to a cam swap and no cam that makes any real change in power can use the stock idle rpm. Its a tech section and people come here to discuss mods and ultimately do them. The ones that stand the test of time and 1000's of installs are worth doing and I dont know anyone that skipped this mod when doing a cam. I see no one complaining about not passing emissions, voltage, current, ect. One more thing. When you get an emissions test done, it isnt at idle rpm.
I have never seen a single person remove one for it having a downside. If you had a stock idle, automaic trans, and had dimming due to huge stereo amps being drawn, you get an OD pulley for the alternator and its done.
AMEN BROTHER
Burning Brakes
Joined: Oct 2006
Posts: 995
Likes: 2
From: Virginia Beach VA
If you raise the idle of the car the alternator is spinning as fast as it was with the stock pulley at the slower idle rpm so no there is no difference between the old and new amperage. Further, if you use an overdrive pulley on the alternator and an underdrive pulley on the crank there is no amperage difference. Not sure why you posted here but just for UD pulley facts: My cousin's 2002 trans am still has the original battery in it. He has an UD pulley on it since 8k miles when I installed it and it now has 112k miles. No issues to this day with any dimming or electrical issues. No there is no downside to a pulley swap. I think GM should use it as stock. But, I do have a theory! I think since they use the same pulley on so many vehicles that may have an issue with the power, its possible that using the same one on the corvette keeps costs down.
Why dont they grind the cam with 208 on the intake side?
Why not mold the TB with the same shape as a ported one?
Why dont they put in a 160 thermostat?
Why do they release the car running so rich from the factory?
Why do they use a restrictive air filter?
Why do they have the air cleaner draw hot air instead of a cool air duct through the shroud?
They have to stop somewhere.
Why dont they grind the cam with 208 on the intake side?
Why not mold the TB with the same shape as a ported one?
Why dont they put in a 160 thermostat?
Why do they release the car running so rich from the factory?
Why do they use a restrictive air filter?
Why do they have the air cleaner draw hot air instead of a cool air duct through the shroud?
They have to stop somewhere.
Burning Brakes
Joined: Oct 2006
Posts: 995
Likes: 2
From: Virginia Beach VA
What pulley?
Now that I'm comfortable w/ the underdrive pulley only my question is by who & from who? My search found:
1. ASP w/ over drive alt. pulley (couldn't find pulley only) 299.00
2. SLP (pulley & bolt only) 225.00
3. MotoBlue (pulley & bolt only) 190.00
Best I can tell, the only differences are pulley material steel or aluminum. Of course everybody wants to sell the belts seperately. Also, if you just go w/ the underdrive pulley what belts do you need?
Shopping on line is great, but if doesn't tell you what is necessary to do 100% install, just what a great price for the main component, it's a half @#$%D way to sell product!
HEY VENDORS, ATTENTION PLEASE! SELL KITS W/ EVERYTHING NEEDED TO MAKE SOMETHING WORK! Just a thought.
1. ASP w/ over drive alt. pulley (couldn't find pulley only) 299.00
2. SLP (pulley & bolt only) 225.00
3. MotoBlue (pulley & bolt only) 190.00
Best I can tell, the only differences are pulley material steel or aluminum. Of course everybody wants to sell the belts seperately. Also, if you just go w/ the underdrive pulley what belts do you need?
Shopping on line is great, but if doesn't tell you what is necessary to do 100% install, just what a great price for the main component, it's a half @#$%D way to sell product!
HEY VENDORS, ATTENTION PLEASE! SELL KITS W/ EVERYTHING NEEDED TO MAKE SOMETHING WORK! Just a thought.
Tech Contributor
Joined: Mar 2003
Posts: 12,094
Likes: 197
From: Colorado Springs, CO
St. Jude Donor '08-'09-'10-'11
It isnt needed.
Supporting Vendor
Joined: Nov 2001
Posts: 410
Likes: 0
Pulley with belts bolt and seal is -
$329.00
Hows that!
I have them in stock as well.
At my other company-ADMPERFORMANCE.COM,we only sell it as a kit.
$299 for Trailblazer SS-Includes belts,bolt and seal.
Andy
$329.00
Hows that!
I have them in stock as well.
At my other company-ADMPERFORMANCE.COM,we only sell it as a kit.
$299 for Trailblazer SS-Includes belts,bolt and seal.
Andy
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