4lb lower

[goldenbear]

Hey guys,

I want to run a 2.93 upper and 4lb lower combo that I've been reading about. I do have a question. In order to get the 4lb lower, am I suppose to buy some sort of interchangeable kit first that will allow me to change the lower to something else? Or can I just buy a 4lb lower somewhere without needing a special kit? I've also been seeing that people change the alternator pulley after changing the lower. Is that necessary? I appreciate the help. Thanks

 

[2003cobra22]

You'll need the complete lower pulley kit because you'll be replacing the stock lower crank pulley along with its cage assembly including the idler pulley, the kit has a bracket that relocates the idler pulley. I have a 4lb lower and run a 3.2" alternator pulley since the larger lower pulley spins the belt faster in turn spinning all other pulleys faster, the pulley helps from over spinning your alternator.

 

[Bigggy]

You'll need the complete lower pulley kit because you'll be replacing the stock lower crank pulley along with its cage assembly including the idler pulley, the kit has a bracket that relocates the idler pulley. I have a 4lb lower and run a 3.2" alternator pulley since the larger lower pulley spins the belt faster in turn spinning all other pulleys faster, the pulley helps from over spinning your alternator.

Everything said ^^

 

[Quick Strike]

The alternator pulley is not really required with a 4# lower. Certainly with a 6#, but you can get away without it using a 4#. My alternator failed at 4K with a stock lower and then went 40K with a 4# lower and stock alternator pulley. I currently have a 2# lower with the same alternator and stock alternator pulley.

 

[goldenbear]

Darn, so I do need that full kit to run a lower? These kits usually run about $250 used, right? Was hoping I could just get a 4lb lower haha. Alright, thanks.

 

[stangfreak]

yep you need the full kit

 

[Tractionless1]

See if you can find a 4# lower that's built into the OE cage as a fellow forum member had a run of them a few years ago. This will keep the OE crank snout support and potentially save future oil pump etc. carnage.