I have the exact same problem.. I have a 3.12, 600cc DW, UTEC

I see 4.5PSI at 5600rpm.. 313hp and at 6600 still the same.. so from 5600rpm to 6600 it is a flat line on the graph.
I'll post a pic of the graph tomorow..

 

I'm wondering if the BPV isn't closing and causing a leak.

Keep your hand in front of the bpv and give it some gas. See if you can feel any air leaking from there.

 

We already did that....at idle its leaking air, but thats normal (apparently), once you give some gas it closes

what bugs me, is the boost graph, it looks really unstable, correct me if im wrong, but shouldn't it show as a smooth line going up? Now, thats supposed to be either a leak or belt slip right? is there any other possibility of another thing thats not working properly that can affect my boost pressure? Its supposed to be in around 20.9-21 atmospheric pressure around 8psi...anything else I can check? Im running out of options...

 

i learn something new everyday on this site (not that i'll ever use that software)

 

flat line is probably belt slip then. the only other option is a damaged impeller and you should be able to see the damage by looking at it.

it won't fully close when you don't have a load on the engine so just giving it a free rev isn't a good way to test if the bpv is closing all the way. You can take the vac line off and it should stay closed. I guess if the spring is bad then it wouldn't hold the pressure it should but that doesn't fit the problem totally.

Plus, during a WOT pull on the dyno if the spring is weak and the pressure is opening the bpv you should be able to put your hand over it and feel air leaking out. I guess that is worth a try.

you don't want to,that software isn't that great.

 

I just can't hear it slipping, and I also thought the belt would be pretty warm if it was slipping... but it don't..

my SC is brand new, the impeller looked new as "never used" before the install.
anyways will try to tighten the belt today..

 

check to make sure that the O-Ring inside the Valve is there..mine was gone and I had a little boost leakage because it could never close fully!

now that I have the Ttrim and the 2.87 on a RevUp I am not going to use it...to drop the PSI down a bit. lol

Dyno today or tomorrow....Ill post results. 600DW, Unichip FTW!

 

Ok so here is a picture of the impeller, it looks perfectly fine to me....also its about 45 to 60 degrees what I can twist the belt...









Is it possible to test just the blower to see how boost it is producing???
Hopefully tomorrow i will go to the shop to test the BPV with my mechanic ....running out of options

 

belts dont make noise when they slip at high speed. you're thinking of squeel when you start a car. different story.

and if your belts aren't getting hot then something's up. after some runs mine are hot enough you can't touch them for more than a couple seconds.

 

that's because you're testing the belt tension in an incorrect place.

You have to test it at the longest belt length between 2 pulleys. Where you are testing it is like 5" at the most between pulleys. You'll never be able to twist that since they are so close.

and you have to test it directly in the middle.

did you close down the BPV bolt to test if hte bpv is leaking?

 

My belt had to be SUPER tight to avoid slip on the 3.12" pulley. It's on like a guitar string...lol.

 

does anyone one know if the 05 06 hr single tb plenum will bolt up to 07 08 hr dual tb plenum? i guess if that can be done then a rev up vortech will work on the 08 hr motor...right?

 

it should bolt up.

 

we tried to tighten the belt yesterday.. it became a little hot, and the pulley bearings began to make an annoying noise. so we loosened it again..
I was worried about the noise from the pulley bearings.. I tought the noise came from there anyways..
man I'm getting frustrated..
Binder. can I get my tuner to call you today maybe?

 

Looks like belt slip my friend...Keep us posted.

 

Ok.... so I/we tried the 3.33 pulley today and the result: 5 psi max
something is wrong.. and the belt is not slipping that's for sure

 

But 5psi or so is normal with a 3.33"pulley.

 

are u sure about that..??

I thought it should make about 6-7psi???

 

Mine would touch 6psi at almost 7K but anything below that would be 5psi or less. I also have stock exhaust which makes boost higher.

 

I don't think so. The runners are designed differently if I'm not mistaken. Also the bracket mounts to the front timming cover not the plenum. Stillen is making a supercharger kit for the HR motor using a vortech blower. Why not use that option?