EGT safe condition!
- Thread starter CarlosPTR210
- Start date
The sole purpose of EGR is to suppress the formation of NOx. Recirculated exhaust gas is composed mainly of CO2 and water vapor. It may be hot but it results in lower combustion temps because these gases are inert to the combustion process. Since they displace atmospheric oxygen in the charge the resulting combustion is cooler. The balance of the atmosphere is 80% nitrogen so exhaust gas not only cools combustion but also results in less nitrogen to bond with oxygen. Nitrogen bonded with oxygen results in oxides of nitrogen (NOx).
EGR's ability to supress detonation comes from it's cooling effect. In fact EGR was first studied for this purpose. The discovery of it's ability to suppress NOx was serendipitous. Removing EGR not only defeats it's ability to suppress detonation but to make matters worse most ECUs advance ignition timing whenever EGR is flowing.
edit: the others beat me to it
EGR's ability to supress detonation comes from it's cooling effect. In fact EGR was first studied for this purpose. The discovery of it's ability to suppress NOx was serendipitous. Removing EGR not only defeats it's ability to suppress detonation but to make matters worse most ECUs advance ignition timing whenever EGR is flowing.
edit: the others beat me to it
.....and BHGs
EGR can be active at times other than steady state cruise but never at WOT or idle. During a heavy load like climbing a hill at less than 4200 rpm (it's cut out point) for example. That's when not having it can bite but as long as knock control is working everything should be OK. Myself, I prefer detonation not occur in the first place.
EGR can be active at times other than steady state cruise but never at WOT or idle. During a heavy load like climbing a hill at less than 4200 rpm (it's cut out point) for example. That's when not having it can bite but as long as knock control is working everything should be OK. Myself, I prefer detonation not occur in the first place.
Ric said:
He does have a wideband
Yep...very old school. A wideband and EGT gauge combo tells you an awful lot about that's happening in your cylinders.
I know of one other that put a hole in the piston without losing the gasket' He was running a composite OEM style.
Good to see you planned ahead though.
Good to see you planned ahead though.
2900rpm, 70-75mph in my auto today did about 2 hours of driving, my EGT's were a constant 1400 sometime going to 1450ish on an uphill, seems a bit high to me, i dont quite have a wideband yet but last time i dynoed my AFR's were off the chart rich, and i have the sender mounted in the 6th runner of the exhaust mani. Im concerened and where should i start looking first?
Your speedometer is wrong or your tach is wrong... unless you custom installed super long gearing.CarlosPTR210 said:
To add to this seeing how I now run an EGT Probe I see mid 400c at low speed cruise 550c at highway cruise and 720c during hard 23psi pulls.
Mine is in the Downpipe about 12" down from the flame front.CarlosPTR210 said:
My DP is Ceramic coated and I run a blankie on the turbine housing so there's isn't much of a temp drop at the probe.
A couple of reasons I didn't install in the collector.
a) PITA to remove the header to weld in a bung
b) The probe is 1/8" stainless steel so not all that sturdy considering the heat involved if the motor does lean out for any reason and the thought of a failure and having the probe go through the Turbine didn't make for happy thoughts.
c) As I posted the temp drop is negligible and I use the EGT to track trends not for tuning.
a) PITA to remove the header to weld in a bung
b) The probe is 1/8" stainless steel so not all that sturdy considering the heat involved if the motor does lean out for any reason and the thought of a failure and having the probe go through the Turbine didn't make for happy thoughts.
c) As I posted the temp drop is negligible and I use the EGT to track trends not for tuning.