Should I put a 6lb pulley combined with a 7" crank to produce 6psi of boost....... or should I just put the 9lb pulley that i already have on it to create the 6psi of boost.. What are the pros and cons of each set up.. thanks,

 

I only get 4 psi with the 6 lb pulley with my setup which I hear is not uncommon with powerdyne.
I'm gonna run the 9 psi pulley which should get me the 6 I want.

 

fast350camaro,
If you run the 7" crank pulley with the 6lb pulley you will overspin your supercharger and blow it up. The supercharger can only spin to 42,000 and that setup will spin it close to 44k at 6,000 rpm on your motor

 

You also have to ask yourself what kind of driving you do.
I only drive my car recreationally and rarely rev my car past 5400 rpm. A higher speed sooner will give you more boost in the lower rpms at the sacrifice of rpm redline.
If you have 2.73's you need the most blower speed soonest.
I'm going with the 9 psi pulley next week.
I'm still only getting 4 psi with the 6 psi pulley.
The 3.73's work excellent with my blower but on the highway in Double OD (2.91 with the GV unit) i get less boost.
So get more boost sooner if you're stock and keep the redline low so your engine will live.
If you're going high rpms then set your blower maximum output to where your redline is and base your pulleys accordingly.

 

That is true, but I shift around 5800 rpm which will not hurt your engine. If you set up your charger your way you just better be careful that you don't forget to shift before redline because you will stress out the charger. There is always more than 1 way to do something I just feel that you should set up your car based on what the engine redlines at that way your not risking anything. My car makes hp up to 5800 before it starts dropping off, so your losing hp shifting at 5400 and trying to make it up with a smaller pulley. Just my opinion. Like I said there's more than 1 way to look at something.

 

I have an A4 and it shifts as soon as I pull back a bit on the throttle.
I want my stock internals 100,000 plus miles engine to live. I've had the blower on a few months now and everything is working great. It is whisper quiet and works great.
I spend almost all my time up to 5400 rpm and very little over.
I prefer more boost and thrills for my all around driving and not peak power at a high rpm that IMO will only kill my engine and blower sooner for a few extra thrills.
My car breaks the 1 inch oversize tires on my car easily and makes me tingle even at the 4 psi I have now.
6 psi will be intense for my type of driving.