Mysterious Lack of Boost
Mysterious Lack of Boost Here's the deal. I can only make 5-6 psi on my supercharger for some reason. Called Procharger directly and they can't figure out why. Figured I'd ask you guys...
specs on the car:
2000 camaro SS ls1
STOCK motor
long tubes and true duals
badass fuel system
specs on the system:
procharger D1sc
3.7 pulley (supposedly 8-9# pulley)
6 rib
NLP extra idler pulley
dual intercoolers
used kit
things i've tried:
obviously checked for leaks. unless its a pinhole or something, i'd have seen it.
notice very little, if any, dusting of the blower belt. belt is new, tightened down to spec, and is a good belt (forgot the brand, sorry) so I really dont think it's slipping anymore. especially since Mike Norris at Next Level installed an additional idler pulley to help with slippage.
tried taking the vacuum line off the bypass valve as suggested in another thread. still only made 5#s
tried eliminating the bypass completely by plugging both holes. still only made 5#s, so i don't think its the bypass valve at this point, even though the unit is very used and i don't think the butterfly valve seals properly. i'll probably replace it anyway.
at this point i'm thinking it's either a leaky intercooler or something or possibly the head unit itself? does anyone have any suggestions? i'm at my wit's end here.... sorry the post was too long!
specs on the car:
2000 camaro SS ls1
STOCK motor
long tubes and true duals
badass fuel system
specs on the system:
procharger D1sc
3.7 pulley (supposedly 8-9# pulley)
6 rib
NLP extra idler pulley
dual intercoolers
used kit
things i've tried:
obviously checked for leaks. unless its a pinhole or something, i'd have seen it.
notice very little, if any, dusting of the blower belt. belt is new, tightened down to spec, and is a good belt (forgot the brand, sorry) so I really dont think it's slipping anymore. especially since Mike Norris at Next Level installed an additional idler pulley to help with slippage.
tried taking the vacuum line off the bypass valve as suggested in another thread. still only made 5#s
tried eliminating the bypass completely by plugging both holes. still only made 5#s, so i don't think its the bypass valve at this point, even though the unit is very used and i don't think the butterfly valve seals properly. i'll probably replace it anyway.
at this point i'm thinking it's either a leaky intercooler or something or possibly the head unit itself? does anyone have any suggestions? i'm at my wit's end here.... sorry the post was too long!
At what point did you notice that it wasn't making the amount of boost that it was supposed to??? I'm thinking that the headers are allowing the engine to flow better so it's not so restrictive...
The older D-1SC's came with 6 rib belts until 2004 or so. It is still an option as you can order a P-1SC kit with it's thinner 3.5" intercoolers and six rib belt and upgrade the blower to a D-1SC. Some places are quoting D-1SC kits this way, which of course makes it cheaper, but the customer gets screwed if they think they are getting the best kit that ATI offers.
My older D-1SC kit is the six rib belt. With a 4.00" pulley on the stock LS1 engine, with Hooker headers, Hooker Off road pipe, and Hooker cat back, the engine produced seven pounds of boost.
The first question that comes to mind, and has already been asked. Are you sure it is not a P-1SC? If you are sure that it is a P-1SC, take a good look at the plenum box, to make sure it does not leak. I have heard of one case where one guys box had a pinhole on the bottom side of it. The six rib belt also needs to be tight enough that you can strum it like a guitar string, you might try tightening it up to see if that takes care of it. I'd go over every square inch of the plumbing, if all else fails, intercoolers also. Good luck! Bob
My older D-1SC kit is the six rib belt. With a 4.00" pulley on the stock LS1 engine, with Hooker headers, Hooker Off road pipe, and Hooker cat back, the engine produced seven pounds of boost.
The first question that comes to mind, and has already been asked. Are you sure it is not a P-1SC? If you are sure that it is a P-1SC, take a good look at the plenum box, to make sure it does not leak. I have heard of one case where one guys box had a pinhole on the bottom side of it. The six rib belt also needs to be tight enough that you can strum it like a guitar string, you might try tightening it up to see if that takes care of it. I'd go over every square inch of the plumbing, if all else fails, intercoolers also. Good luck! Bob
well... its never really made more than 5-6#s... I always thought this was odd since I posted earlier asking how much it was supposed to make and got estimates at high at 10#s... either way, according to everyone i've asked about it, I should have at least 7.... even with the engine flowing more... I know the exhaust will help a bit, but is it worth 3#s of boost? it's not like I have a cam or heads or anything...
i'm 100% sure it's a D1, I will check though, just in case... I bought the kit used so it's one of the older style i'm sure...
see, that's what makes me think something's wrong with my ****... I have a little better flowing exhaust, but a lot smaller pulley than you... and I only have 5?!?!? ARGH!
edit: ok just got back from the garage... the head unit IS a D1... for sure... i checked the intake box and intake pipe for leaks and found none... everything else in the system checks out ok as well, no hoses off, etc...
does anyone have an easy way to check the intercoolers for leaks?
i'm 100% sure it's a D1, I will check though, just in case... I bought the kit used so it's one of the older style i'm sure...
My older D-1SC kit is the six rib belt. With a 4.00" pulley on the stock LS1 engine, with Hooker headers, Hooker Off road pipe, and Hooker cat back, the engine produced seven pounds of boost.
edit: ok just got back from the garage... the head unit IS a D1... for sure... i checked the intake box and intake pipe for leaks and found none... everything else in the system checks out ok as well, no hoses off, etc...
does anyone have an easy way to check the intercoolers for leaks?
Last edited by sslow2000; Sep 4, 2006 at 12:56 PM.
10 Second Club
Joined: Dec 2002
Posts: 315
Likes: 0
From: Baton Rouge,LA
Are you sure the bypass valve is getting boost? If you have it hooked up at the wrong spot(downstream of the check valve) it will never close. That will keep it open and you wont build boost, i ran mine like that for a while until I could get it tuned.
the bypass valve is in the stock procharger location and IS installed correctly. i've checked it numerous times... 
I did inspect the valve and it should probably be replaced... (doesn't look like it seals as well as it should) but i tried all the procedures to check that it works (used the search button! ) and ruled out the valve as the problem. I don't really know at this point. i think im going to somehow get a guage installed before the intercoolers to see if i'm losing boost through them...
I did inspect the valve and it should probably be replaced... (doesn't look like it seals as well as it should) but i tried all the procedures to check that it works (used the search button! ) and ruled out the valve as the problem. I don't really know at this point. i think im going to somehow get a guage installed before the intercoolers to see if i'm losing boost through them... 
