Has your pulley thrown a belt?
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Which brand was it?
I am basicly trying to find out which aftermarket crank pulley is the most likely to throw the belt, as I have herd this can be a problem.
Thanks.....
I am basicly trying to find out which aftermarket crank pulley is the most likely to throw the belt, as I have herd this can be a problem.
Thanks.....
Last edited by taws6; 11-29-2008 at 04:51 PM.
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If your talking about the Serpentine belt tensioner and pulley assembly.....
On my 2001 LS1 motor that I had in my 98 Z28, I had a bad problem with it throwing belts at around 4500 rpm. I actually had to replace the Belt and the Tensioner b/c the stock tensioner was SLIGHTLY worn and was leaning outwards just enough to throw the belt off at higher rpm's.
This problem is VERY common on LS1 engines. Katech has a tensioner for around $150.00 or so. (Maybe Less??) And they have a higher edge than the stock pulley does to prevent slipping or thrown belts. The tensioner IMHO is the main reason for the belts being thrown but other people argue that it's b/c of the pulley. I think maybe a little of both.
But if your talking about the Crank Pulley throwing the belt, An ASP or SLP Underdrive pulley is a good Underdrive Pulley to go with for the LS1 Engines...
Good Luck!
James
On my 2001 LS1 motor that I had in my 98 Z28, I had a bad problem with it throwing belts at around 4500 rpm. I actually had to replace the Belt and the Tensioner b/c the stock tensioner was SLIGHTLY worn and was leaning outwards just enough to throw the belt off at higher rpm's.
This problem is VERY common on LS1 engines. Katech has a tensioner for around $150.00 or so. (Maybe Less??) And they have a higher edge than the stock pulley does to prevent slipping or thrown belts. The tensioner IMHO is the main reason for the belts being thrown but other people argue that it's b/c of the pulley. I think maybe a little of both.
But if your talking about the Crank Pulley throwing the belt, An ASP or SLP Underdrive pulley is a good Underdrive Pulley to go with for the LS1 Engines...
Good Luck!
James
Last edited by LT1Formula007; 11-29-2008 at 04:34 PM.
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I have almost the same setup as you, an Alpine Type R sub, Kicker 480W amp, and an A4 with a Summit Racing Underdrive Pulley (taller walls so you don't have to worry about throwing belts and a great price, Summit has been sending some $25 off $100 purchase so you might be able to find a coupon code) and the only time the voltage would drop below 13 is when I was at idle and both radiator fans were running, if only one was running then I was fine. I have HP Tuners and bumped my idle up from 550 to 650 and with the stereo on, headlights on, both fans running, and at idle I stay right at about 13. When driving I am always at the typical 14.4V. So if it is possible, get your idle bumped up 100rpms. I also used a main belt that was .25" shorter than what summit recommended.
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Great, I hope to get a baby tune soon, so I can adjust my idle then.
So should I get the crank pulley AND alt pulley?
I have bought some stuff from summit before, where could I get a coupon from?
So should I get the crank pulley AND alt pulley?
I have bought some stuff from summit before, where could I get a coupon from?
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asp pulleys throw belts, slp and powerbond(which are the same might i add) are the same, i have a powerbond and it never threw a belt ever and i bounce off the rev. as far as alt pulleys, if ur runin an aftermarket stereo system(subs/speakers) then yea get the alt pulley. if ur not runin a system then dont wry about it, it wont effect charging hardly at all. i just have the underdrive crank pulley on and i lost like half of a volt charging wise.
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It looks like you are gonna get advice both ways on this one but with the $$$ you put in your sound system I would spend $25 to make sure it gets all the juice it needs cause low current makes electronic stuff run hot and affects longevity.
I have no cool stereo like you plus my idle is set 900-925 so I run UD only with no issues.
I have no cool stereo like you plus my idle is set 900-925 so I run UD only with no issues.
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as far as alt pulleys, if ur runin an aftermarket stereo system(subs/speakers) then yea get the alt pulley. if ur not runin a system then dont wry about it, it wont effect charging hardly at all. i just have the underdrive crank pulley on and i lost like half of a volt charging wise.
Keep in mind he has a auto...
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1. Say at 550rpm the alternator rotates 1000 times, with the crank pulley it will rotate 750 times (25% underdrive) and with the increase in idle it will rotate 886 times (at 650rpms, 750*650/550).
2. Say at 550rpm the alternator rotates 1000 times, with the crank pulley it will rotate 750 times and with the overdrive pulley it will rotate 863 times (15% overdrive, 750*1.15)
So it is your choice, alternator pulley or tune, but the increased idle will actually give you a better charge. I never actually did these calculations before, I could probably even reduce the idle to about 625rpms and be close to what the alternator pulley would give me, maybe help gas mileage a little bit.
Last edited by vjo90rs8; 11-30-2008 at 07:58 PM.
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So do I![Happy](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_stretch.gif)
And FYI a friends ASP had the plastic damper stuff start cracking after about two years. I have only had my March about seven months but a buddy has an ATI and it still looked good after 3 1/2 years and 30k when we pulled it to fix a dying oil pump recently.
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And FYI a friends ASP had the plastic damper stuff start cracking after about two years. I have only had my March about seven months but a buddy has an ATI and it still looked good after 3 1/2 years and 30k when we pulled it to fix a dying oil pump recently.
Last edited by SOMbitch; 11-30-2008 at 08:36 PM.
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It basically comes down to, do you want to increase the idle 75-100rpms or do you want to buy the alternator pulley, one would be FREE if you are getting a tune anyways and the other will be $25 which is pretty cheap. Totally up to you and as I described earlier the idle speed change (100rpms) will give you a better charg than the alternator pulley and I like the higher idle, didn't notice any change in gas mileage and it seems to idle a bit smoother. Also, you must decide before you install the crank pulley because it will require a different belt if you get the alternator pulley.
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It looks like you are gonna get advice both ways on this one but with the $$$ you put in your sound system I would spend $25 to make sure it gets all the juice it needs cause low current makes electronic stuff run hot and affects longevity.
I have no cool stereo like you plus my idle is set 900-925 so I run UD only with no issues.
I have no cool stereo like you plus my idle is set 900-925 so I run UD only with no issues.