Longtube header/O2 sensor question
Thread Starter
Burning Brakes
Joined: Jun 2006
Posts: 1,096
Likes: 28
From: Baltimore MD
Longtube header/O2 sensor question
Guys that have swapped to longtubes, what are you doing about the O2 sensor? Assuming, obviously, the headers didn't have an O2 bung already in place. Example: Hedman Elite 68448
Thread Starter
Burning Brakes
Joined: Jun 2006
Posts: 1,096
Likes: 28
From: Baltimore MD
hmmm. I saw Hedman makes a collector with a bung already in it, but have to wonder if that puts the sensor too far away? Hot Rod 90, how close to the collector was your bung welded in?
Racer
Joined: Dec 2005
Posts: 384
Likes: 0
From: Chicago IL
I have modified hooker 2149 headers. The air fittings are removed and I have o2 bungs in each collector and the headers are jet hot coated inside and out by a local place called lo-ko coatings. I also run a 4 wire heated o2 from a buick roadmaster. you can pick up the o2 from any parts store.
No problems at all.
No problems at all.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Racer
Joined: Dec 2005
Posts: 384
Likes: 0
From: Chicago IL
aside from the sensor, you just need to wire it up. The 4 wire has 4 wires.
I forget so double check:
1 wire goes to ecm
1 wire goes to switched 12 (can tap into wiper motor and put small fues on there)
2 wires are grounds
The buick roadmaster (which has a 350 v8) heated o2 is proabbly the best option.
I forget so double check:
1 wire goes to ecm
1 wire goes to switched 12 (can tap into wiper motor and put small fues on there)
2 wires are grounds
The buick roadmaster (which has a 350 v8) heated o2 is proabbly the best option.
Last edited by tntcorvette; Dec 30, 2006 at 01:14 PM.
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
http://forums.corvetteforum.com/show....php?t=1401956
I run a 3 wire heated O2 with my stock manifolds.
I run a 3 wire heated O2 with my stock manifolds.
Safety Car
Joined: May 2003
Posts: 4,283
Likes: 0
From: Houston Texas
I am also running a 3 wire sensor with my TPIS long tubes. Made all the difference in the world with my 92. Black wires is sensor wire. Pick one white wire to go to a switched ignition source so it is only on with key on and ground the other white wire. I think the 4 wires are only for the 96's and OBD2.
Drifting
Joined: May 2003
Posts: 1,979
Likes: 48
From: Lakeport CA
TPIS LT has a bung on drivers side collector. I ran stock non-heated for a number of years with no issues but upgraded to heated a few years back. Switched 12V source (same one I used for my Accel ignition box) & a ground.
Last one I installed was from listed as stock for a '94 vette. Any online parts place you can look it up for a price match at your local dealer.
I now have also purchased a wide band, I installed a bung in the passenger side collector, same area as the one TPIS did on the other header. It also works great, readings matched what I got from the dyno shop who had a sniffer in the tail pipe.
Le Mans Master
Joined: Jun 2001
Posts: 6,694
Likes: 3
From: Less Talk, More WOT | Houston TX
Thread Starter
Burning Brakes
Joined: Jun 2006
Posts: 1,096
Likes: 28
From: Baltimore MD
I actually went my own route on this...I welded an O2 bung 10" from the header flange, on cylinder/primary tube #7. It works fine, and eliminates need for heated O2 sensor. I used a stock replacement oxygen sensor.
Hedman offers the collectors with the bungs already welded in...but you'll need the heated O2's with them...
http://www.hedman.com/pages/reducers.html#2
Hedman offers the collectors with the bungs already welded in...but you'll need the heated O2's with them...
http://www.hedman.com/pages/reducers.html#2
Safety Car
Joined: May 2003
Posts: 4,283
Likes: 0
From: Houston Texas
A 1 wire non heated o2 sensor has to wait to be heated to a certain temperature by the exhaust to start reading. The 3 and 4 wire sensors have a heating element in them to preheat them in order start reading the exhaust gases sooner. Long tube headers have the sensors down in the collector farther away from the heads, so they have a tendency to take longer to heat up or at idle, like mine, would start to cool off due to low exhaust volume and heat. Until the sensor reads the gases the car is in open loop.
Instructor
Joined: Nov 2006
Posts: 207
Likes: 0
From: Duluth Georgia
A 1 wire non heated o2 sensor has to wait to be heated to a certain temperature by the exhaust to start reading. The 3 and 4 wire sensors have a heating element in them to preheat them in order start reading the exhaust gases sooner. Long tube headers have the sensors down in the collector farther away from the heads, so they have a tendency to take longer to heat up or at idle, like mine, would start to cool off due to low exhaust volume and heat. Until the sensor reads the gases the car is in open loop.
