O2 operating temp-question??
O2 operating temp-question?? Just received a new set of Hookers with O2. The sensors will install in a 3" to 2 1/2 pipe to the rear of the collectors.
I used to own a Holley fuel injec setup with O2 sensor installed in the 3 in collector. At this, the operating temp of the collector barely reached the required 600 deg F(proven by me) at idle per Holley directive. Because of this, I ran very rich at idle, until engine speed produced enough heat for proper closed loop operation. Wrapping the collectors created enough insulation so that closed loop could operate normally.
Here's my question...the new headers will mount the O2 even farther back than my old set. Do you think this could cause an issue at low engine speeds w/closed loop?
Edit: Forgot to mention that the old Holley setup was a Chevy 350, and the new setup is a 98 LS1.
Thanks.
I used to own a Holley fuel injec setup with O2 sensor installed in the 3 in collector. At this, the operating temp of the collector barely reached the required 600 deg F(proven by me) at idle per Holley directive. Because of this, I ran very rich at idle, until engine speed produced enough heat for proper closed loop operation. Wrapping the collectors created enough insulation so that closed loop could operate normally.
Here's my question...the new headers will mount the O2 even farther back than my old set. Do you think this could cause an issue at low engine speeds w/closed loop?
Edit: Forgot to mention that the old Holley setup was a Chevy 350, and the new setup is a 98 LS1.
Thanks.
Last edited by gMAG; Dec 18, 2007 at 11:18 AM.
yes our cars definitely suffer from the same problem; some worse than others. It is particularly worrisome with larger cams as well. Fuel trims wander positive trying to get the voltage up but the heat just isn't there for the sensor to work properly. It's usually liveable, but definitely happens. If you are a proactive person, wrapping before the sensor and just after helps, but no one seems to want to do this. I am told that a side effect of wrapping coated headers is early coating demise, but I'd rather replace headers every 3-4 years and have my car fueled right at idle personally.
The Holley fuel inj sys had the ability to adjust closed/open loop to any speed desirable.
Do you know if the LS1 computer can be programmed the same way, for instance, to run open loop until the engine hits, say, 1600 RPM...then, run closed to higher speeds?
This ability might make for a smoother running engine, rather than an engine which hunts looking for closed lp at low RPM.
Thanks!
Do you know if the LS1 computer can be programmed the same way, for instance, to run open loop until the engine hits, say, 1600 RPM...then, run closed to higher speeds?
This ability might make for a smoother running engine, rather than an engine which hunts looking for closed lp at low RPM.
Thanks!
