Could all you out there with 5.3's equipped with the MP112 magnacharger using a 3.3" pulley give me your boost numbers with mods? Just ordered a 3.3" pulley for my 112 and want to know how much boost I will make.

 

depends on your intake and exhaust. I would expect ~7lbs. on average.

 

I have that exact setup you are inquiring about. With mods in sig and my 3.3" pulley I'm seeing 8~7.8 lbs. of boost. Like Trever1t says, your boost will depend on your intake and exhaust setup. I had 7 lbs. when using the stock 3.4"
pulley. Hope this helps.

 

I have the 3.3" pulley on... but I have no boost gauge so I am of no help to you. But 7-8 psi is the majority opinion from what I have read.

 

Im bought a magnacharger 112 with a 3.3 pulley for my 4.8. I will have it on maybe next weekend. So what ever my boost number is yours will definatly be alittle lower...

 

What about the 122HH? would numbers go down because of larger displacement blower, or up due to the rotor difference?

 

Got a mp122 installed with mods in sig and im seeing 8.5 on a 3.2 pulley.

 

I have a 4.8 with the mp112 stock exhaust, running a 3.7 pulley and getting 6.5 to 7 lbs. of boost