What EGT are you seeing at high speed?
#1
What EGT are you seeing at high speed?
Yesterday I went out on my favorite stretch of highway and got up to about 120 mph in fifth. I was monitoring EGT, and I got nervous and backed off at about 1500F. I was surprised it got that high, since I was at partial throttle and not boosting. At least I think I was not boosting - I never looked at the boost gauge, being fixated on the EGT. I was definitely at partial throttle though, so the ECU was in closed loop mode. This makes me wonder what temperature the ECU will allow when in closed loop operation.
For you guys that have checked, what EGT are you seeing at partial throttle, high speed?
On a side note, I did a compression check yesterday and my compression is unchanged from the last time I checked it, before I installed the SC. Plugs looked great, except the number two plug showed very slight indications of high temperature (tiny slivery deposits).
For you guys that have checked, what EGT are you seeing at partial throttle, high speed?
On a side note, I did a compression check yesterday and my compression is unchanged from the last time I checked it, before I installed the SC. Plugs looked great, except the number two plug showed very slight indications of high temperature (tiny slivery deposits).
#3
if I partial throttle to enter a freeway from 30mph to 80mph, it will hit my 780C limit. so that's 1430F. If I boost, from 65 to 100mph @ 10psi, it will go up to 720c....which is 1328F.
regarding the plugs.....where did you see the silver deposits? I thought high temperature usually mean white and melted insulators.
regarding the plugs.....where did you see the silver deposits? I thought high temperature usually mean white and melted insulators.
#4
Originally posted by [maxi-overdose]
if I partial throttle to enter a freeway from 30mph to 80mph, it will hit my 780C limit. so that's 1430F. If I boost, from 65 to 100mph @ 10psi, it will go up to 720c....which is 1328F.
regarding the plugs.....where did you see the silver deposits? I thought high temperature usually mean white and melted insulators.
if I partial throttle to enter a freeway from 30mph to 80mph, it will hit my 780C limit. so that's 1430F. If I boost, from 65 to 100mph @ 10psi, it will go up to 720c....which is 1328F.
regarding the plugs.....where did you see the silver deposits? I thought high temperature usually mean white and melted insulators.
The deposits are on the insulator and electrode.
#5
Originally posted by Stephen Max
When boosting I only get as high as you do, about 1430-1450F. But then the afr is being controlled by the fmu. It's only at partial throttle and at high speed that I see it go higher.
When boosting I only get as high as you do, about 1430-1450F. But then the afr is being controlled by the fmu. It's only at partial throttle and at high speed that I see it go higher.
same here...when I partial throttle it to 80mph....it hits my EGT limit.
#6
Originally posted by [maxi-overdose]
I remembered that I had this discussed with you....did we every figure out why partial throttle will increase EGT faster than boosting? I initially thought it was the FMU that's not able to detect small amount of boost (1 - 2 psi) but after I installed the fuel pressure gauge...seems a little tap of the gas pedal will push the fuel pressure. @ 1 - 2psi, my fuel pressure is about 49psi. either the FMU reacts to it....or it is just factory FPR.
same here...when I partial throttle it to 80mph....it hits my EGT limit.
I remembered that I had this discussed with you....did we every figure out why partial throttle will increase EGT faster than boosting? I initially thought it was the FMU that's not able to detect small amount of boost (1 - 2 psi) but after I installed the fuel pressure gauge...seems a little tap of the gas pedal will push the fuel pressure. @ 1 - 2psi, my fuel pressure is about 49psi. either the FMU reacts to it....or it is just factory FPR.
same here...when I partial throttle it to 80mph....it hits my EGT limit.
#9
Originally posted by bags533
i see about 700 C at 130 ish, but I am very rich... 11:1 at that point
i see about 700 C at 130 ish, but I am very rich... 11:1 at that point
#10
Originally posted by bags533
i see about 700 C at 130 ish, but I am very rich... 11:1 at that point
i see about 700 C at 130 ish, but I am very rich... 11:1 at that point
#13
EGT's at part throttle are going to be higher because the efficiency of the blower and the fact that above atmospheric pressures are inside the intake manifold giving more power without boosting enough for the fpr to come into the play with higher fuel pressure. As the throttle is applied boost will be sensed by the fpr and you will see a richer condition = lower egts. I was on a trip just last week to Destin with 4 passengers and 400lbs of luggage and my egts on a long uphill grade cruising at 85 with the a/c on would hit 790c. It would only get that high up a long constant uphill. I got a little nervous when I saw that but it mostly stayed around 720 cruising at 85. Stock injectors suck I wish we had an option for some side fed 320cc without having to get dramatic with 370cc and use an aftermarker regulator.
#14
Originally posted by AllGo
EGT's at part throttle are going to be higher because the efficiency of the blower and the fact that above atmospheric pressures are inside the intake manifold giving more power without boosting enough for the fpr to come into the play with higher fuel pressure.
EGT's at part throttle are going to be higher because the efficiency of the blower and the fact that above atmospheric pressures are inside the intake manifold giving more power without boosting enough for the fpr to come into the play with higher fuel pressure.
going uphill kicks the EGT up to 800c..same here.
#15
Originally posted by Stephen Max
In the y-pipe, just below the front bank O2 sensor, i.e. a couple of inches below the front header.
In the y-pipe, just below the front bank O2 sensor, i.e. a couple of inches below the front header.
#16
Originally posted by joaquink
Did you dyno-tune and watch the EGTs with the probe there? The absolute value can vary drastically. Someone seeing 1400F with the EGT probe near the junction in the Y would probably notice more like 1500-1500+ in the location you're at. I'm up real close to rear header with my EGT and have my fields checking the front bank - not perfect but it'll do for now. I haven't dynotuned but would expect my temps to be higher than the standards set by people who have their probes further downstream when I do.
Did you dyno-tune and watch the EGTs with the probe there? The absolute value can vary drastically. Someone seeing 1400F with the EGT probe near the junction in the Y would probably notice more like 1500-1500+ in the location you're at. I'm up real close to rear header with my EGT and have my fields checking the front bank - not perfect but it'll do for now. I haven't dynotuned but would expect my temps to be higher than the standards set by people who have their probes further downstream when I do.
I havent't dyno-tuned yet. My daughter enters UT in the fall, so there are all kinds of expenses that need to be taken care of first.
#17
Originally posted by joaquink
Did you dyno-tune and watch the EGTs with the probe there? The absolute value can vary drastically. Someone seeing 1400F with the EGT probe near the junction in the Y would probably notice more like 1500-1500+ in the location you're at. I'm up real close to rear header with my EGT and have my fields checking the front bank - not perfect but it'll do for now. I haven't dynotuned but would expect my temps to be higher than the standards set by people who have their probes further downstream when I do.
Did you dyno-tune and watch the EGTs with the probe there? The absolute value can vary drastically. Someone seeing 1400F with the EGT probe near the junction in the Y would probably notice more like 1500-1500+ in the location you're at. I'm up real close to rear header with my EGT and have my fields checking the front bank - not perfect but it'll do for now. I haven't dynotuned but would expect my temps to be higher than the standards set by people who have their probes further downstream when I do.
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