Please clarify this for me. I am under the impression that the stock lt1 crank pulley has a built in damper(or all in one pulley/harmonic damper). Yes or no?

 

Yes, it does. Were you just needing an answer to this question or are you wondering how an underdrive pulley system works with an LT1?

 

I was just making sure the previous owner of my engine didn't part the harmonic damper off of the engine without telling me.

Because, from what I've been reading about underdrive crank pulleys I started to think the damper and crank pulley were two different entities. So when I looked at my crank pulley and all I seen was a pulley I got a little worried.

Thanks for letting me know the stock pulley and damper were one in the same. But aftermarket stuff is one or the other, unless specified correct?

 

The only underdrive pulley (besides the SFI dampners) that has is a dampner too is the ASP 23% pulley, all of the other ones just piggy back onto the stock pulley.

 

well the stock lt1 damper/pulley assembly is three pices. the hub that bolts onto the crankshaft and seals against the front cover seal, the pulley which is sandwiched in between the hub and damper, and the damper itself which has three bolts in it holding the damper and pully to the crank hub. all the aftermarket under drive pulleys that i have seen just replace the pulley in between the hub and damper.

 

That's not a stock setup, theres a hub then pulley that bolts to the hub. Nothing else.

 

i thought my car was 100% stock when i bought it and i have worked an a few other lt cars and they all had a 3 pice design. the damper has ribbs on the outside like a pulley but is not used. the pulley that actually drives the belt is seperate and much smaller than the damper. maybe i am wrong, do i have an underdrive pulley? anyone got pics of a stock setup?

 

well after some quick research i stand corrected. i am amazed i have had the car for five years and never realized. this must be why my ac sucks at idle.

 

Shoebox has a photo of everything....

http://shbox.com/1/pull_pulley.jpg