Mangled03gmc

iTrader: (95)

I am kinda baffled why my boost stays flat from 34-5100. I am running the 3.4 pulley and which is supposed to be good for 10lbs correct.. I am going to make a few pulls to 6k to see if the boost moves any. I am running a k&N filter, using the procharger coupler that mates the filter to the unit.. There isn't any blocks in the air route, so I dunno what gives. If the blower was messed up it wouldn't even boost at all, the impeller and all seems fine, no leaks from it.. Now on to the cam, I have said this before, but is it really possible for a 112lsa cam to bleed 3-4psi of boost off... I dunno

Thanks John

Raffman

iTrader: (9)

How about your exhaust sys? cats?

BlackGMC

iTrader: (31)

Does your setup have a BOV, if it does is it working properly????

Mangled03gmc

iTrader: (95)

No BOV but does have the bypass valve. As far as my exhaust it has LTS no cats dumped blowmaster, that could pos be part of it, I dunno how procharger is getting the psi numbers, threw stock exhaust. That would make less boost with out all that restriction.. Also the heads have been worked a lil, comp valve job, what not. Maybe my bypass valve needs adjusting. I just want to get enough info to head me in a direction here..
Thanks fellas

John

Silver-Dollar

iTrader: (1)

Would it be the other way around? More restriction, more psi (not necessarily HP). The free flowing exhaust, messaged heads, and 112 lsa should reduce the psi seen. The only culprit to bleed anything off would be the cam. I do not know for sure, but from everything that I have read, it would seem that this would be the case.

sharpshooter

iTrader: (10)

Procharger recommends LSA's from 112-116
here is some suggestions
1.is bypass butterfly fully closed when no vacuum is applied
2.belt slip on small pulley
3.is all intake holes closed off [pcv system & crankcase vent from passenger valve cover to intake]
4.is a P1SC maxed because of your mods[cam,heads,exhaust] I don't think so.

I still think you will get your boost with more rpm's.I see 10#'s @ 5900 with a D1SC & my cammed 6.0 using a 4.25" pulley.

phasemaster1

iTrader: (11)

John I would still check that bypass valve maybe stuck open I think Superado had his stick at the track was #10 and suddenly #7? I remember you said you could still blow through it when you got it, I have the proflow new style one and its does the same. Normal I dont know maybe I can tell you this weekend. Good luck.

Jaime

02BlueStepside

iTrader: (1)

I would guess a bad bypass or belt slip. I have a 4.1" pulley on my little 4.8 and hit 10lbs. Don't know enough about cams to say if it is bleeding off any boost. Look around the blower pulley, and other pulleys for that matter and see if you see any dust. I had a 3.6" (I think) on mine when I first got it and just cruising around (not under boost as I wasn't tuned for that pulley) it would slip and you could see dust.

Raffman

iTrader: (9)

Yes that's true, restrictions cause more boost. With the small pulley and through the muffler I see 14lbs but at the strip with exhaust cutout open see only 11lbs or so. You can pull that bov off easy enough to see if it's working properly.

Mangled03gmc

iTrader: (95)

Ok heres what I have found as of earlier tonight. In which case makes a lil better sense to me. My bypass valve when at idle is open, again before I put this on I could blow threw it when closed, it wasn't air tight. I have talked to a few about it and it seems thats the way they work, they don't get air tight. Next I went out later today for a ride, let the ole girl eat, ran it up to 6k, but before I made that run I messed with the bypass screw, so I dunno if it was that or just cause I ran up up in the rpm's but I seen 7 psi, but that was at the very very top of 5900-6k. So on the way back, had a lil tangle with a SS camaro(Another story) anyway I heard a noise. Turnd out my belt started to come apart. So now I am thinking that the belt that was on there was too loose, I might have been slipping it. Now that it has been mentioned, that pcv tube that goes from the TB to the pass side V cover is not connected, so there may be some more psi missing. I will plug that tom, I didn't even think about that. I went and purchased a new one the next size down, put it on, but havn't done any testing to see if that helped, that will be tom, when I get some logs. I am sure the psi is being puked off by cam overlap. So hopefully the smaller belt and a plug in that line will be where it is.
Again guys I really app your help.. I will report back..

Thanks again

John
John