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For Sale Ported LSJ exhaust manifold
Ported LSJ exhaust manifold
Got another spare so this is the one I had ready for my car. Need money for parts for the Sonic 
Fully smoothed, collector opened up , flanges resurfaced, ready to go on the car and make more power than any other shorty setup with less noise and zero reliability problems. IMO the only way to go unless you're shelling out the cash for a big long-tube setup.
Looking to get $120 shipped. THIS ONE IS SOLD. SEE POST #14 for the second one.
Fully smoothed, collector opened up , flanges resurfaced, ready to go on the car and make more power than any other shorty setup with less noise and zero reliability problems. IMO the only way to go unless you're shelling out the cash for a big long-tube setup.
Looking to get $120 shipped. THIS ONE IS SOLD. SEE POST #14 for the second one.
Last edited by ItalianJoe1; Apr 28, 2014 at 08:31 PM.
Yeah Gennix has this one but i'm gonna see about getting his old one back. As of right now I still have another stocker that is destined for my car, it hasn't been touched but I'll start on it as long as I have time. If I know there is another one coming from a previous buyer or whatever, I can sell that one too when it's ready.
I started doing the other one I bought for myself today, if I have time this weekend I will probably be able to finish it, I should be able to stop by the machine shop tomorrow and i'll resurface the flanges when i'm there. Another one will be up for sale soon
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Sweet. Pm me when it's done and we can set up payment and shipping! I've been torn on a header for a while. I never even considered your ported stock one as an option. I'm an idiot lol.
https://www.cobaltss.net/forums/2-0l...nifold-278302/
This is probably the only real comparison that was ever done. I don't bother to measure it, it's too complex of an area to give a simple measurement and act like that's the difference. Point is, it flows way better than stock and according to him it outperformed his shorty header, which has been my experience also.
This is probably the only real comparison that was ever done. I don't bother to measure it, it's too complex of an area to give a simple measurement and act like that's the difference. Point is, it flows way better than stock and according to him it outperformed his shorty header, which has been my experience also.
Just wondering but...don't the stock manifolds crack all the time? I have mine and 2 other friends that i've swapped manifolds out and they've all been cracked. Also heard of many others who have had stock ones crack...
The GMPP is a stock casting that has been extrude honed. The link I posted was a GMPP originally. It makes them very smooth inside anywhere there are high spots, it pushes an abrasive material through them and works well for the most part. What I do removes all the casting flaws and markings, and actually re-shapes the area around the O2 sensor and removes some of the other larger restrictions. A ported manifold will move more air because there's just less material in the way/larger passages. The smoother manifold will flow better but will still be limited to pretty much the original inside diameter, it just takes on a nice polished finish inside.
Last edited by ItalianJoe1; May 1, 2014 at 07:17 PM.
Only one I've ever seen crack, was my original stock manifold. It was on my car for three years and was run lean to the point of being glowing red, had dozens of bottle of nitrous run though it, etc. It had started to develop a small crack around the inside of the collector, and when I removed it it spread pretty good. That's the only one i've personally handled that was cracked and the abuse I gave it would have cracked any manifold.
Well it's hot here in Miami so I doubt it's that.
Yeah, welding cast iron isn't worth it, they are very likely to crack again right next to the weld and they are cheap enough to just buy another used one for the cost of trying to repair it.
Usually, it's a stress thing and they may have a very small crack that expands greatly once you remove it from the engine. I always re-surface the flanges and they are nowhere near flat when I get to them usually. All that movement is from stress in the metal formed from repeated heat cycles.
Yeah, welding cast iron isn't worth it, they are very likely to crack again right next to the weld and they are cheap enough to just buy another used one for the cost of trying to repair it.
Usually, it's a stress thing and they may have a very small crack that expands greatly once you remove it from the engine. I always re-surface the flanges and they are nowhere near flat when I get to them usually. All that movement is from stress in the metal formed from repeated heat cycles.