Anyone else have any thoughts about their being a nose drive that you cannot change the pulley on?

someone correct me if i'm wrong, but the only time that's true is if you have an underdrive or overdrive crank pulley

Here ya go. http://cgi.ebay.com/ebaymotors/3-0-Q...Q5fAccessories :D

I'm using a 3.3" pulley on my 5.3L and seeing 8 psi with mods in sig.
(stock heads):(

So no one knows for a fact how or why the nose drives would be different on a Joe Gibbs edition MP112 vs. buying one directly from magnacharger?

The nose drives are different. Pulleyboys makes both styles. You can contact them about whatever pulley size you want. I posted a link in my previous post. Hope this helps you.

How about posting a picture to let us see what yours looks like?

There are a ton of factors that will affect how many lbs of boost a person is making. intake, TB, Cam, Heads, compression ratio, exhaust will all affect the psi.

When you are measuring psi you are measuring how much pressure is built up in the intake manifold of your motor. Pulleying down and leaving everything else stock will increase psi and increase power, now add a nice cam and a free flowing exhaust and your psi will decrease, but your power will increase even more because you have removed a restriction.