Car makes 11 lbs boost???
 

With all the reading I have been doing I figured I would be losing boost. My cam specs are 231/243 .617/.624, I also have ported and polished stock ls3 heads with 1 7/8 long tube headers. I didn't plan on supercharging my car but Jessika made me such a good deal I couldn't pass it up, so I bought a magnuson 2300 with the overdrive pulleys. Just looking for one of the experts thoughts. Like I said before I figured boost would be less. (5-7 lbs)

My car made 11.5psi on the dyno with a stock ecs kit and longtubes, which i thought would actually bring down the boost a bit. Was expecting around 8-9.

Are you running a NA cam also? I thought I would be less boost with the cam, heads and headers. Not complaining, car runs awesome, just not what I was expecting. Ihave spent hours reading threads about overlap, losing boost out the exhaust valves, lower boost with ported heads, etc. Now just looking for a better education.

I made 15.3lbs of boost on my NA cam with the ECS Kit.

This would be why.

Stock ls3 cam

plus if you have cats on the car it will create restriction in the exhaust which will increase boost levels.

No cats.

No cats

Two different types of blowers, One is a PD, other is Centri. The ECS kit runs a bit more boost then the PD does. Also, OD pulleys will increase Boost levels.

What size pulley do you have up front? I think it takes a whole lot bigger cam with more overlap than you have to really "bleed" boost.

Stock pulley up front. And you just kinda answered my question. I guess I wanted to know when I started to lose boost.

Just sayin they advertise 9lbs and i thought with the headers and no cats it would of been a little less.

First off, :)
The 3.8 front pulley and 1:1 rear should make 6ish. The OD on the rear should put it to 9.5ish.

Lately it seems like everyone is making more boost than in the past... it is odd. Anyway, do you have a dyno sheet? Just curious...

Brandon/Suxost or however it is spelled also is making higher than average boost but he is running HF cats.