Ok guys quick question. What pound is the factory crank pulley on an 01' L? I now have a 6lb. lower and also want to know how much boost I'm creating now? Any help will be greatly appreciated!!

Thanks,
01_White_Light

 

ahhh.. THere's two answers:

The easy answer:
the stock pulley makes 8# of boost, your 6# pulley will add 6# of boost ON TOP of the 8# you make stock, so you will end with 14# of boost.

The technical answer:
Who knows... Why?
Many aftermarket pulleys differ in size. It is known that JDM pulleys are larger diameter than JLP pulleys classified as the same poundage. A JDM 4# is the same size as a jlp 5#, and close to my LFP interchangable 6#. SO the best way is to measure the diameter of the pulley where the belt rests and post that.

ALso, Boost is the measure of backpressure. Many things effect that, the cleanlinest of the I/C, the exhaust you are using any restictions in the air flow. So your gauge may read a higher boost number doesn't necessarily mean you are making more power.
I make more power now that i have freer flowing exhaust and LOWER boost on my gauge, than I made with a higher reading on my boost gauge.

 

What exhaust application are you using? Right now I have the stock muffler, but I do have my cat's and resignators cut. So, as of right now I'm not sure if I should change my exhaust or leave it as is. Any suggestions on a muffler?

 

That stock Catalytic convertors are the biggest bottleneck of the exhaust, then the stock exhaust manifolds (which happen to be the same part as the regular n/a 5.4L F150).
Seems like you cured that restriction.

I have bassani headers, custom made mid pipes with high-flow cats and baffles, MAC cat back.

 

If you are looking for a little free flowing muffler, but not to loud try this


I hear chickenears has good prices on it

 

I don't know who was the first first vendor to start selling lower pulleys for these trucks, but they ought to have their a$$ kicked for marketing them claiming certain lbs. of boost gain. Must be a ricer.

Pulleys need sold according to the diameter and nothing else.