I plan on taking the exhaust off my blazer in favor of straight headers. How long of an exhaust pipe do I need to have after the collectors so that the O2s don't go crazy?
I plan on taking the exhaust off my blazer in favor of straight headers. How long of an exhaust pipe do I need to have after the collectors so that the O2s don't go crazy?
99 Silverado 4.8l : Soon to be 80E swapped, then 6.0 swapped, ......
05 Yukon Denali 6.0l : Nelson Performance Tune, ......
8X S10 Blazer on a 8X 3/4 ton frame : 5.3l swapped, Nelson Performance tune, Schoenfeld LT's, 226/226 .598/.598 112, TH350, planetary doubler, NP 205, locker, spool, 38's, ......
I have 6" cats on mine. The o2's are happy. Hope your truck isn't a DD though, drone is insane between 1500 and 2000 RPM. Which is cruise for me in 5th gear. I'll drop to 4th just to avoid the drone.
Last edited by Frenchy; 07-23-2013 at 04:05 PM.
2006 SilveradoLittle Black Bitch
No, it's not a daily driver. It's my mud truck/blazer. I was planning on running a foot of pipe off the collectors and was wondering if it would be enough. Seems like it may be if you're running a 6" cat.
99 Silverado 4.8l : Soon to be 80E swapped, then 6.0 swapped, ......
05 Yukon Denali 6.0l : Nelson Performance Tune, ......
8X S10 Blazer on a 8X 3/4 ton frame : 5.3l swapped, Nelson Performance tune, Schoenfeld LT's, 226/226 .598/.598 112, TH350, planetary doubler, NP 205, locker, spool, 38's, ......
to be honest im not sure if this will help you any. i just thought id throw this in the mix. especially sinced you helped me out alot with the flexplate ordeal. lol! anway, i fabbed up this temp exhaust until the 80e is in and im getting an o2 code "out of range" i havnt really checked too much into it but i dont see any other problems on the truck other than the massive exhaust leak i have on these pipes. (there is an identicle one for the other side)
the flange and both sides of the cat i fully welded on. but both sides of the muffler, i only put 4 tacks on it which hold it together. lol the extension between the cat and muffler is no more than 8" so the o2 is prolly about 6" from the leak....
like i said idk for sure if the leak is my problem but im guessing it is..... if i was you to be on the safe side, id go at least a foot like you were saying. then you dont have to worry about it. like i said, this prolly doesnt help too much but i figure id let you know.
and in case your wondering, YES!!!! IT IS EXTREMELY DRONY INSIDE THE CAB!! lol but it being so short along with the slight leak, it sounds badass outside the cab.....
Last edited by kewljay223; 07-24-2013 at 08:23 PM.
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I decided on keeping the exhaust on and not running straight pipes. My exhaust is exactly like yours except for the cat and rear o2. It sounds damn good too which is one reason I decided to leave it alone. Another reason is on the passenger side the pipe has a couple bends to get around the transfer case. Forgot about that and don't want to cut up my exhaust just to make it work.
99 Silverado 4.8l : Soon to be 80E swapped, then 6.0 swapped, ......
05 Yukon Denali 6.0l : Nelson Performance Tune, ......
8X S10 Blazer on a 8X 3/4 ton frame : 5.3l swapped, Nelson Performance tune, Schoenfeld LT's, 226/226 .598/.598 112, TH350, planetary doubler, NP 205, locker, spool, 38's, ......
You are correct. About a foot of pipe after the front o2 sensors is needed to keep you from tripping codes and the truck running like crap
2000 GMC Sierra 1500 RCSB 2wd - 454 LSX powered drag truck...