Stock manifold pic
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Junior Member
Joined: 12-02-05
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From: Wichita Kansas
Stock manifold pic
Anyone else's stock manifold look like a half moon like mine where the DP connects???
http://i3.photobucket.com/albums/y56...aderpix021.jpg
http://i3.photobucket.com/albums/y56...aderpix021.jpg
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Joined: 11-24-04
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From: newark, DE
so that is the air injection manfold? its a new emiision setup from what i just learned on 06+ ls cobalts and such.... did you put on a aftermarket header? and are you having and CELs?
if not this is good!
(good meanign you can remove air injection manifolds
if not this is good!
(good meanign you can remove air injection manifolds
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Joined: 08-18-06
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From: Visalia, CA
Yeah I took mine off just to see and it looks Exactly like that... what in the hell were them people smoking? what a waste of freakin metal! Im eyeballing the cobaltaddiction's exaughst header just because the way ours are designed.
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Joined: 09-08-06
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From: *
My 06 2.2 LS had the "D" shaped exhaust manifold too. It is 1 15/16" at the largest area. GM probably did it to get as much of the exhaust to the O2 sensor for emissions control. Hurts performance without a doubt.
I replaced it with the GMPP extrude honed exhaust manifold -- which has a 2.25" round hole. Exhaust flow must have increased by more than 20 percent! Imagine how much air must be passing through there at 4-6000 RPM.
How much better is the extrude honed manifold over the stock 2.4 and SC versions???
I replaced it with the GMPP extrude honed exhaust manifold -- which has a 2.25" round hole. Exhaust flow must have increased by more than 20 percent! Imagine how much air must be passing through there at 4-6000 RPM.
How much better is the extrude honed manifold over the stock 2.4 and SC versions???
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Joined: 12-02-05
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From: Wichita Kansas
No I do NOT have the air injection on my 2.2, thank god. I was doing a shorty header install, ran into a snag, so the stocker is back on for now. I just took this pic when I pulled it off. Seems like the GMPP would yield some good gains on the 2.2 since this manifold is so damn restrictive.
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Joined: 09-08-06
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From: *
GM finally fesses up as to what the extrude honed exhaust manifold is -- found at: http://www.Chevrolet.com/cobalt/accessories
We've taken the production LSJ exhaust manifold and had it etrude honed. The result? Larger and smoother paths and a 7% airflow improvement for more power. Combine it with the Cat-Back Exhaust (sold separately) for an even better performance exhaust.
For those of you with the 2.2, who don't want a header, this manifold provides a greater increase in performance than it does on the LSJ engine by replacing the more restrictive stock 2.2 manifold pictured at the start of this thread. Still don't know what the stock 2.4 manifold is yet.
We've taken the production LSJ exhaust manifold and had it etrude honed. The result? Larger and smoother paths and a 7% airflow improvement for more power. Combine it with the Cat-Back Exhaust (sold separately) for an even better performance exhaust.
For those of you with the 2.2, who don't want a header, this manifold provides a greater increase in performance than it does on the LSJ engine by replacing the more restrictive stock 2.2 manifold pictured at the start of this thread. Still don't know what the stock 2.4 manifold is yet.
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Joined: 02-22-06
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From: Colorado
Originally Posted by Cobalter LS
GM finally fesses up as to what the extrude honed exhaust manifold is -- found at: http://www.Chevrolet.com/cobalt/accessories
We've taken the production LSJ exhaust manifold and had it etrude honed. The result? Larger and smoother paths and a 7% airflow improvement for more power. Combine it with the Cat-Back Exhaust (sold separately) for an even better performance exhaust.
For those of you with the 2.2, who don't want a header, this manifold provides a greater increase in performance than it does on the LSJ engine by replacing the more restrictive stock 2.2 manifold pictured at the start of this thread. Still don't know what the stock 2.4 manifold is yet.
We've taken the production LSJ exhaust manifold and had it etrude honed. The result? Larger and smoother paths and a 7% airflow improvement for more power. Combine it with the Cat-Back Exhaust (sold separately) for an even better performance exhaust.
For those of you with the 2.2, who don't want a header, this manifold provides a greater increase in performance than it does on the LSJ engine by replacing the more restrictive stock 2.2 manifold pictured at the start of this thread. Still don't know what the stock 2.4 manifold is yet.
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Joined: 11-16-05
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From: Central NY
I see alot of people have been screwing around with thier 2.2 exhaust manifolds, How long does it take to get one of these damn things off the engine? How did you do it, and Do you have any tips on preparing to get it off?
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Joined: 08-07-06
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From: New York
Whats the best manifold out at the moment, if the GMPP gives 7% more air flow- what do the others promise? does anyone know, and is a high percentage better or do the effects of higher air flow tapper off atlike 15% more then stock? Basically if its going to effect toque - when does it start causing a major loss.
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From: *
I have all 3 GMPP mods -- I/M/E. I can't say how much more the performance is over stock because I put them all on with less than 1000 miles on my car and had not "floored" it before the mods. I am VERY pleased with the get-up-and go now. The hardest part of the manifold remove/install was getting the three nuts holding the down pipe on. Best method is to get under the car and use 1/2" drive 15 MM deep socket setup. All the nuts on top (three heatshield bolts too) use a 13MM deep socket -- these were no problem. Make sure to get the manifold-to-head gasket, three new studs for the Down pipe connection, and the manifold-to-down pipe gasket. Took all of 45 minutes to do, and I took my time.
The original listing for the GMPP manifold was that it was for the LSJ engine with no other information. It is a basically a polished LSJ manifold -- LS owners will actually get the most benefit/gain out of it because they're replacing a more restrictive manifold.
The original listing for the GMPP manifold was that it was for the LSJ engine with no other information. It is a basically a polished LSJ manifold -- LS owners will actually get the most benefit/gain out of it because they're replacing a more restrictive manifold.
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Joined: 03-23-06
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From: Orlando, FL
exactly.
I swapped the stock LSJ manifold in place of my stock 2.2 and noticed a huge difference in where power delivery was, smoother pull up top, and better milage. once I actually sprayed on it I realized how much better it flows. I can actually get traction in 2nd now because the LSJ unit flows enough to move my peak torque up a bit, as opposed to landing right in the crest of it on my 1-2 shift. sounds a bit deeper and slightly louder now too. you can also find them relatively cheap from SS/SC or Redline owners. I'd definitely suggest it for anyone looking for a cheap upgrade but want to keep oem durability. if you run a sleeper game like me you definitely will benefit from it.
I swapped the stock LSJ manifold in place of my stock 2.2 and noticed a huge difference in where power delivery was, smoother pull up top, and better milage. once I actually sprayed on it I realized how much better it flows. I can actually get traction in 2nd now because the LSJ unit flows enough to move my peak torque up a bit, as opposed to landing right in the crest of it on my 1-2 shift. sounds a bit deeper and slightly louder now too. you can also find them relatively cheap from SS/SC or Redline owners. I'd definitely suggest it for anyone looking for a cheap upgrade but want to keep oem durability. if you run a sleeper game like me you definitely will benefit from it.