LT1 crank pulley question
#22
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Been using my bbk underdrive pulley for around 8 months the way the instructions told me too which was to take my old one off and put on the bbk underdrive pulley and everything has been fine. Doesn't say anything bout needing a balancer to go with it. But hey that's not what I know, that's what bbk says.
if your running your engine without a balancer your on borrowed time. Is your setup a under drive balancer or a under drive pulley thats just a pulley
part number?
#23
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I am sure it has its benefits but right now, I won't be making any use of them.
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I called BBK when I bought mine from here and they told me to take off my old balancer and hook up the new under drive pulley. They never said anything bout putting the old one back on with it. Thanks for the info though defenentily gonna out my old balancer back on with it. Thats most likley the reason my rotor button came unscrewed. Thats what I get for listening to someone over the phone that prolly doesn't know jack about what they are selling.
#25
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I called BBK when I bought mine from here and they told me to take off my old balancer and hook up the new under drive pulley. They never said anything bout putting the old one back on with it. Thanks for the info though defenentily gonna out my old balancer back on with it. Thats most likley the reason my rotor button came unscrewed. Thats what I get for listening to someone over the phone that prolly doesn't know jack about what they are selling.
![](http://shbox.com/1/temp_sensor1.jpg)
If you look at this picture you can see the rubber "gasket" between the two halves of the Damper. This is usually what goes bad on an SBC damper, causing the outer ring to shift and cause an imbalance in the rotating assembly. Since BBK sells this whole unit as it's underdrive pulley, you will not have to worry about it. Only in the older SBC's were the Damper and Pulley separate...Like on the L98 in the ThirdGen's. Our Pulley/Damper is of the same basic design as that on the LSx motors. Have no fear you are not causing any damage to your engine by running an underdrive pulley.
#26
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Yes, I agree. But having to buy an underdrive pulley to get a couple of HP is not worth it to me, I will still need an OEM pulley or aftermarket damper either way. So I could put the money elsewhere.
I am sure it has its benefits but right now, I won't be making any use of them.
I am sure it has its benefits but right now, I won't be making any use of them.
#27
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I wouldn't worry about your BBK. If you take a close look at the Harmonic Damper and the Crank Pulley you will realize they are one in the same. You cannot remove the pulley without destroying the damper.
![](http://shbox.com/1/temp_sensor1.jpg)
If you look at this picture you can see the rubber "gasket" between the two halves of the Damper. This is usually what goes bad on an SBC damper, causing the outer ring to shift and cause an imbalance in the rotating assembly. Since BBK sells this whole unit as it's underdrive pulley, you will not have to worry about it. Only in the older SBC's were the Damper and Pulley separate...Like on the L98 in the ThirdGen's. Our Pulley/Damper is of the same basic design as that on the LSx motors. Have no fear you are not causing any damage to your engine by running an underdrive pulley.
![](http://shbox.com/1/temp_sensor1.jpg)
If you look at this picture you can see the rubber "gasket" between the two halves of the Damper. This is usually what goes bad on an SBC damper, causing the outer ring to shift and cause an imbalance in the rotating assembly. Since BBK sells this whole unit as it's underdrive pulley, you will not have to worry about it. Only in the older SBC's were the Damper and Pulley separate...Like on the L98 in the ThirdGen's. Our Pulley/Damper is of the same basic design as that on the LSx motors. Have no fear you are not causing any damage to your engine by running an underdrive pulley.
but most under drive setups are just a cheap light weight pulley that is not capable of dampening the harmonics of the engine thus requiring your old balancer to be bolted to the front of it
#31
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as retarded as it sounds thats what most under drive pulleys require(at least for the LT1) notice how most under drives are refereed to as pulleys and not "underdrive dampeners"
#32
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Well since every LTx I've ever seen and worked on that had an underdrive pulley never bolted the Damper on the outside of it and never had any vibration issues.....I guess I'm wrong......
BTW, if the manufacturers of said pullies planned on you bolting the damper to the outside I would assume they would ship them with longer bolts to accomplish such feat, but since I've never seen one come with said bolts, I'd have to assume they don't intend you doing that.....
BTW, if the manufacturers of said pullies planned on you bolting the damper to the outside I would assume they would ship them with longer bolts to accomplish such feat, but since I've never seen one come with said bolts, I'd have to assume they don't intend you doing that.....