boost problems with a 2.8, need help.
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Joined: 10-12-11
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From: florida
iim guessing a vacuum, or boost leak too, but i dnt have the time stuff to even test for a leak, and i can definatly feel the loss of torque and power..but im gonna check my exhaust today for a leak.. but idk, but im with u cause my friend with same mods as me is hitting 18psi with his 2.8 and m62 with 60s...
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From: Blue Earth MN
problem is nothing u have told me i didn't already know, intake + exhaust = less boost more power because it is less restricted....duh i get that i'm telling u that with my intake and exhaust it was still at 17-18psi(at 65 degrees outside), now at any temp its 15-16psi, and a power loss, cause i have a leak or two, so i will re-due my intake cause the gasket is bad or backwards or not torqued right w/e, i heard the leak! and then i shall post pics if it get it squared away, i know for a fact my car is less powerful then it was when i installed my ****!
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From: Blue Earth MN
iim guessing a vacuum, or boost leak too, but i dnt have the time stuff to even test for a leak, and i can definatly feel the loss of torque and power..but im gonna check my exhaust today for a leak.. but idk, but im with u cause my friend with same mods as me is hitting 18psi with his 2.8 and m62 with 60s...
no he is not ur boost dropped becouse u got exhaust are u guys like 16 wtf
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Joined: 10-12-11
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From: florida
I was gonna check my exhaust for loose bolts, thought I had an exhaust leak, cuz it's been sounding raspy lately,.. Like airy.. Not cuz of the loss of boost.. As far as my loss of power and differences between me and my friends Balt, is he has the full 3" zzp exhaust, where I have the mixed up 2.5"-2.7" injen intake, so when I did the 3" exhaust, I lost alot of backpressure!..= loss of boost.. Duh I know.. I'm jus hoping when I get the zzp 3" intake next week, that thatll help the blower get more air and up the boost atleast to solid 16 cuz right now my "stage 3 sc cobalt w/2.8 pulley" runs like a stock ss with a cold air.. :/
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Joined: 10-12-11
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From: florida
And yea he is i watch him pull away from me while I'm boosting 14 psi... Plus I was with him when he walked an sti on the interstate at 120... And those go up to 20 psi depending on what they have it set too..
that and iam pretty sure i put my gasket on backwards, that could be my leak right there, cause now its down to 13-14psi, at 54 degrees.....now remember i still have a manifold not header, and a cat!
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Joined: 09-11-10
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From: Harrisburg Pa.
ya i bought two of the three lines, the two that are attached to the by-pass, and new gaskets, intake to block, and super to intake, new by-pass, and new super oil. so ya iam just going to re-due the intake cause i saw a pic of the way it was suppose to go on and i put it on backwards and hope that does the trick.
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From: Blue Earth MN
lol and you do i would ******* know i had a 2.8 for over a year my boost gauge read 18 my areoforce read 14 and HPTuners read 14 so u shut up cuz u dont know **** i make 18 with a 2.6 but whatever **** this thread u guys are stupid
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From: New Jersey then. Now Orlando Florida
you dont know what your talking about. Opening up the exhaust will equal less boost but in a good way. Also stock boost gauges are not very accurate. On a 2.8 your gettting 15psi
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Joined: 10-12-11
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From: florida
dang someone isnt getting butt hurt, nothing with a little debate 16 year old, through out your opinion, if what you said hes already done,then thats not the problem. trial and error, and eventually someone will point him in the right direction, and for the guy talking about gauges and hptuners.. thats fine if u had a gauge that said 18, but hptuners said 15 and aeroforce said 15.... BFD!... the point is correct or not, the gauge he is reading from stock or not?! used to say 18, now the weather is getting colder and his gauge is reading 13-14... same thing with me....-.- so even if we were doing 15 psi the whole time and our "boost gauge" was lying to me telling me 18. im still 4psi short! sooooo, maybe he really only doing 10 psi??? cuz i guess our gauges dont work, and mine is not the stock boost gauge. think someone has a big head and needs to help solve the problem instead of having a di#% measuring contest over email...
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Joined: 10-12-11
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From: florida
and zzp evens says i should be getting atleast 17 psi with a 2.8... oooooooooo someone should find out whats wrong with there car!!!! 80
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From: Harrisburg Pa.
Since I put full 3 in exhaust on my car after stage 3 kit and haven't lost no boost I would say YOUR wrong
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Joined: 10-12-11
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From: florida
K só i have a checo enfune light. P2610... New probability for me is that my Car is in a low power mode and thats why I'm not boosting 16-18psi... So I'll see what happens..
Check engine*
Check engine*
Last edited by stones07ss/sc; Oct 14, 2011 at 05:32 PM. Reason: Automerged Doublepost
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Joined: 10-12-11
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From: florida
K so, got, my car dyno, and tuned, 4th gear pull I did 266 whp, 241 ft lbs tq, @ 17.01 psi... That's on a 2.8" pulley... So the guy who said 15 psi on a 2.8, no more can suck it, and I have mid length headers with 3" cat back, and the zzp true 3" intake... Plus some other stuff. 
Joined: 05-18-11
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From: West Chicago, IL
subd. my car has .. well read my sig. been feelin kinda sluggish lately too, i think its due to having my exhaust too open, as u dont need a free flowing exhaust with s/cs.. i know u knew that. but yea def. get those leaks fixed, get retuned, u might b able to pull back
