Ok I know most of the 03-04 Cobra guys upgrade the lower pulley and also the lower crank pulley so I looked for the same for the SS.I found this one..
http://cgi.ebay.com/ebaymotors/Chevy...spagenameZWD1V

It's not a "underdrive" it's the same diameter but it claims to weigh 2.5 times lighter than OEM.For the price it doesn't seem worth it but has anyone bought one or similar?

 

yeah mrz makes that piece

 

I bought a JBP version of this but I didn't notice anything. About the only thing it would be noticeable in is throttle response I'm sure. 5hp is not going to be something you will feel.

 

Even if you dont feel it, I'd still like to see a before/after dyno of lightweight pullies on our car.... I'd be interested in getting this too.

 

Yeah, but for the price if it isn't that noticable I have a few other things I need to buy first.

 

yeah, ouch, I just noticed the $170 price tag, definatly other priorities first

 

I've been asking for one since they were first made. People don't realize that a crank damper can increase power by increasing its damping ability, the stock ones are a two part piece with rubber between them to absorb crankshaft torsional flex, a solid pulley loses this ability and could actually cost power. Not saying thats the case here, but its a good possibility.

 

Well JBP did dyno it with a 5whp gain...

 

Thats pretty decent then, for $170... I have a few things on mylist to buy first, but it doesnt sound like a bad buy later.

 

Ehh I just realized there was already a thread about this..