Only seeing 2lbs on the 2.4
Only seeing 2lbs on the 2.4
If the bypass valve is good, and there is no leak, what else is there to check? The dyno numbers aren't lying either (176tq).
Is a slight growl at idle normal? You can barely hear the s/c whine at WOT.
Is a slight growl at idle normal? You can barely hear the s/c whine at WOT.
More Boostage! Drop that pulley!
If you aren't making boost or hearing it... that would be your problem... or not an open enough Intake. I REALLY doubt it is belt slip... unless you have a really large belt on there. And if it was a leak... you'd still hear the S/C loud and clear.
At least I think...
If you aren't making boost or hearing it... that would be your problem... or not an open enough Intake. I REALLY doubt it is belt slip... unless you have a really large belt on there. And if it was a leak... you'd still hear the S/C loud and clear.
At least I think...
More Boostage! Drop that pulley!
If you aren't making boost or hearing it... that would be your problem... or not an open enough Intake. I REALLY doubt it is belt slip... unless you have a really large belt on there. And if it was a leak... you'd still hear the S/C loud and clear.
At least I think...
If you aren't making boost or hearing it... that would be your problem... or not an open enough Intake. I REALLY doubt it is belt slip... unless you have a really large belt on there. And if it was a leak... you'd still hear the S/C loud and clear.
At least I think...
how do you know that your bypass valve is good? It probably wouldn't wine much if the bypass was open, but it may still put in some pressure at WOT due to the small bypass opening. I'd bet the the engines have around the same crank pulley sizes and what not, so i'd think that 3.34 would boost significantly for the 2.4. 10lbs of boost is plenty
With the vehicle off... you can start by opening and closing the By-Pass manually. It should be relatively smooth... and should return by itself to its original position.
is the belt hot right after the dyno run... thats a good indicator that the belt is slipping. how much boost is it running? you never told us.
also these blowers are pretty quiet unless you have a loud cai intake on them. and also most guys are revving the 2.0 to at least 7k rpms what is your 2.4 revving to?
also these blowers are pretty quiet unless you have a loud cai intake on them. and also most guys are revving the 2.0 to at least 7k rpms what is your 2.4 revving to?
is the belt hot right after the dyno run... thats a good indicator that the belt is slipping. how much boost is it running? you never told us.
also these blowers are pretty quiet unless you have a loud cai intake on them. and also most guys are revving the 2.0 to at least 7k rpms what is your 2.4 revving to?
also these blowers are pretty quiet unless you have a loud cai intake on them. and also most guys are revving the 2.0 to at least 7k rpms what is your 2.4 revving to?
is the belt hot right after the dyno run... thats a good indicator that the belt is slipping. how much boost is it running? you never told us.
also these blowers are pretty quiet unless you have a loud cai intake on them. and also most guys are revving the 2.0 to at least 7k rpms what is your 2.4 revving to?
also these blowers are pretty quiet unless you have a loud cai intake on them. and also most guys are revving the 2.0 to at least 7k rpms what is your 2.4 revving to?
It says, " Only seeing 2lbs on the 2.4"
So are you running the stock S/C pully from a cobalt? The 3.4"
Last edited by M-Dub; Sep 28, 2007 at 03:18 PM. Reason: Automerged Doublepost
Yeah that's all I'm seeing. I'm with the car right now, we are going to adjust the belt on the pulley to see if it helps any but that's all I can do.
Switched the bypass valve with another ss/sc bypass valve and the same thing happens.
We also sprayed all the connections, manifold and what not to check for leaks and we have no leaks. Stumped.
Switched the bypass valve with another ss/sc bypass valve and the same thing happens.
We also sprayed all the connections, manifold and what not to check for leaks and we have no leaks. Stumped.
Last edited by pjk91; Sep 28, 2007 at 04:17 PM. Reason: Automerged Doublepost
Well a bigger displacement engine will make less boost then a smaller one running the same blower but I would have thought the stock pulley from the 2.0 should have been good for more then 2 pounds of boost. Like said above check the belt since you already checked the bov. If you still got nothing looks like your gonna need a pulley swap.
Why does everyone think that just because it's larger it will show less on the gauge? If the head flow's a significant amount more air then YES it would show less but his numbers blow so it's belt slippage.
less will show on the gauge because theres more room in the cylinders and more vaccuum created by them t suck the boosted air in, lowering manifold PSI, but it would only be lowered 1-2 PSI, not 8PSI, so thats definitely not the reason its not working
guys... rebel did this swap and they showed 8lbs i believe with the stock pulley (like he has).. boosting 2lbs is horrible, obviously something is wrong..
checking belt slip would be my first guess
checking belt slip would be my first guess
I guarantee the bypass valve actuator is good. I'll let you know why. I went down to SMG autosports today to try to help this cause, to drop off my Turbo manifold to get ported, and to get a touch up on my tune.
In the search for the problem We switched my working bypass valve actuator off my car and put it on his, Same results, I ended up taking his bypass valve actuator and sticking it on my car so we didn't have to take it off his again, call us lazy but at least we know that its not that piece. And it works find on my car now.
To see if it was the belt or the SC (early suspicions were that the SC was junk) we undid the valve (plugged the vac line), so it was in the closed position all the time and revved it, where it showed 5lbs of boost.
SO..... the real question is, why doesn't the bypass valve close when the actuator is hooked up??
Thats what we need an answer to to solve the problems.
Bet you didn't know that did you PJK?
In the search for the problem We switched my working bypass valve actuator off my car and put it on his, Same results, I ended up taking his bypass valve actuator and sticking it on my car so we didn't have to take it off his again, call us lazy but at least we know that its not that piece. And it works find on my car now.
To see if it was the belt or the SC (early suspicions were that the SC was junk) we undid the valve (plugged the vac line), so it was in the closed position all the time and revved it, where it showed 5lbs of boost.
SO..... the real question is, why doesn't the bypass valve close when the actuator is hooked up??
Thats what we need an answer to to solve the problems.
Bet you didn't know that did you PJK?
I'm guessing that the air solenoid that switches to open/close the bypass vavle.. Either its not hooked up right, or its not functioning correctly, keeping the bypass valve slightly/open mostly closed




