hmm, you know I think you're right. Dunno where I got the 18ga from, but yeah Summit's site says 16ga too. My bad.

 

on my way home from work today, the truck was running horrible and even thought I heard a knocking. Right after the knocking, started running good again. Service engine soon light came on and I got it scanned. Trouble codes are p0152, p0154, and p1153. First two are O2 sensor codes. One said high voltage and the other said basically that it wasn't there. The p1153 code is something to do with air metering. I changed the plug wires today, so I can rule that out. Called allen today, and the 160 stat program wouldn't affect it he said. So the only thing left is the o2's. I know they are heated o2's. Could the no muffler thing make them not heat up enough? My previous exhaust had no mufflers either, but that was with stock manifolds and cats. Let me know what you guys think. I'd rather not hurt this engine this soon.

 

Hey, you said you basically don't have mufflers, do you have cats? Are you having O2 sensor problems also? Mine worked before the headers, it would be hard to believe they died right then. Too much of a coincidence. Let me know how your muffler install goes for ya.

 

This is not exactly the same, but just for info. I did a cat back MBRP exhaust and lost some low end power, and 2 MPG's. But revs and has much more power on the top end.
This was really surprising to me since I still have factory cats and manifolds. And no I am not driving with my foot in it all the time to hear the exhaust.

 

I'm not so sure that the headers are really to blame on the power loss other than the fact that they flow better. Something is going on with them o2 sensors. When I unplug the front o2's it drives ok (but just ok). When I plug them in, it must just flood the engine. I couldn't even get up to the 30 mph speed limit today. Once I unplugged them, instantly cleared up. I've been told by a couple people that when they are unplugged, the computer goes into a safe mode, which isn't optimum for power, but keeps ya going. Anybody heard of this said safe mode?

 

install a or some mufflers,and youlle be good ,i had the same thing happen to me.put dyanomax straight throughs on and wollaa ,got my low end back.ii tink youre geting too much flow.thus losing low end due 2 no backpressure.try it i bet itll work out for ya.it only takes 15 min too put a muff on.cant hurt anything.you can get some pretty abnoxious mufflers if its the noise you like.i also took off my x pipe and lost power,then i threw a set of hi flow cats and regained my power again.i do have pacesetters also.

 

I had gutted cats before the long tubes, now its longtubes and ory pipe, no cats. I havn't had any lights or o2 problems. I ran it the other day from a stop, and it seemed to do pretty good. The only difference is I filled up at a place that didn't have that damn corn in its gas, so that may help. My muffler just came in today, so I won't be able to get it done until Monday possibly. I will update as soon as I can.

 

Not sure if your muffler is the problem or not.....but i can run my cutout open all the time and not get any ses lights from my stock cam 5.3?
Now it does have a little pipe after the y to get to the cutout but if it's open then it's like having the y-pipe maybe 2foot of piping then free exhaust and i gain power everywhere when it's open....
maybe get some new o2 in there and if it doesn't fix the problem just bring em back?

 

I'm definately going to have to try that. The way the exhaust is routed, I'm going to have to just get a couple glasspacks or something. Wouldn't be able to put anything too bulky on. My dad's camaro has some odd looking glasspacks. He calls them chambered mufflers. They are a straight thru glasspack, but they have dents all over them. They came stock on his 69 camaro, and they sound pretty good. I thought about trying them.

 

I'm thinking that has something to do with you having the y pipe into one. I didn't put the pacesetters into one, I am running duals, which I'm finding might not be the best way. Having the y pipe might have enough backpressure to give you good o2 reading. I never figured that having no mufflers would be a problem, but with the duals, it seems to be.

The driver side o2 sensor is reading fine (i'm thinking because there are more bends in the pipe and longer length of pipe). The passenger side basically goes straight out of the header and takes one 45 degree turn in front of the rear tire. Which, what everybody seems to think, including me now, not enough backpressure on that side.