When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Remember that just because the chart says it is an 11.5 psi pulley does not mean you will see 11.5 psi. You might see more, you might see less. Boost is relative to restriction. For example I lost 3 psi when I put ported heads on my car, but I am sure it picked up power.