Pulley size and boost levels
 

I know a lot of us out there are curious what a specific pulley will do for boost, and how much each mod will effect that. I just got my TVS1900 on and running well a few days ago, but I thought it may not be a bad idea to start a thread dedicated to the boost people see with their given mods. If you could show a bit of a timeline and how each mod effected you as you went that would be helpful for most as well.

I'll start it off

I have a TVS1900 on an LQ9 with a 3.2" pulley. I have ARH 1 7/8" headers, and a 3" cat back, a 222/226 cam on a 114 LSA with negative overlap (see the cam specs in the image below). It was a muggy night and I saw 5# of boost occasionally hitting 5.5#.

Here is a quick video of my gauges

5psi on cammed 6.0 LQ9 - YouTube


And the picture of cam specs.


http://denalitrucks.com/gallery/albu.../cam_specs.png




I'm curious where the rest of you stand, and how much each mod and pulley change effected your specific car or truck. Everyone can guess, but I think most people would appreciate actual results and experiences others have had.

I have a similar cam on 112+4 and a smaller MP112 supercharger. I am running a 2.9 pulley and I see 7 PSI max. I know the cam is holding me back so I think a better boost oriented cam would give me another 2.

How much overlap do you see at .050?

TVS 2300 , 10% overdriven, 8 rib 3.3 blower pulley, 217/229 114.5 +2 LSA. 12psi normally, if temps are below 60 I am close to 13psi.

Did you run a 3.3 blower pulley prior to the 8 rib overdrive upgrade? How much boost did you see from that change alone?

I will have to look at my spreadsheet this evening. I will post up once I figure it out.

I found my sheet and with my cam specs I am running 0* of overlap at 0.050" of lift. I still feel this is holding me back as most boost friendly cams are running much more negative. (i.e. GT2-3 = -23.5*)

Going 10% overdriven I gained 2-2.5lb

TVS 1900 here, 2.7" pulley and 10% overdriven. Seeing nearly 11psi on my 383. I Gained 1.5psi going from 2.8 to 2.7". Can't remember what I had before with other pulleys. My cam has 0 degrees overlap.

That's moving a lot of air for only 11 PSI... must run really strong.