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Old 07-01-2003, 08:28 PM   #31
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dbtk2 - What do you say to this comment by one of the Moderators, JR's3800.??

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Because this will cause the combustion temps to rise causing burnt valves and or cracked exahust manifolds in the long run, much in the same manner as the 92 bonneville without the EGR valve.... This is why it was reintroduced into the 93 and later models...
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Old 07-02-2003, 02:33 AM   #32
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dbtk2 - What do you say to this comment by one of the Moderators, JR's3800.??
Quote:
Because this will cause the combustion temps to rise causing burnt valves and or cracked exahust manifolds in the long run, much in the same manner as the 92 bonneville without the EGR valve.... This is why it was reintroduced into the 93 and later models...
I am assuming they are saying why the EGR valve is there??? If that is what they are saying, it doesn't seem to make any sense to me. Why would not having that hot air pour in all the time increase combustion temps? I have never heard anything like that before, the ONLY reason for the EGR is for emissions. That is ALL.

I will tell you that our '92 Olds 88, I am assuming doesn't have the EGR since it is the same as a '92 Bonneville, ran as good as the day we bought it with 10k on it when we sold it at 193k. I didn't see any negative effects of not having EGR. It actually ran a LOT better than our current '93 Olds 88 with 112k on it, which does have EGR.
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Old 07-02-2003, 04:31 AM   #33
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I am assuming they are saying why the EGR valve is there??? If that is what they are saying, it doesn't seem to make any sense to me. Why would not having that hot air pour in all the time increase combustion temps? I have never heard anything like that before, the ONLY reason for the EGR is for emissions. That is ALL.

I will tell you that our '92 Olds 88, I am assuming doesn't have the EGR since it is the same as a '92 Bonneville, ran as good as the day we bought it with 10k on it when we sold it at 193k. I didn't see any negative effects of not having EGR. It actually ran a LOT better than our current '93 Olds 88 with 112k on it, which does have EGR.
I agree with you based on my own experience with removing EGR....even though it is an older carburated engine.
I'm still going to do it. I'm still wondering if the intercooler is necessary to do it to lower the combustion temps to acceptable levels with this more modern engine.....JR's3800 point about air to fuel ratios....but it still seems to be a reasonable risk because I don't run that hot for that long....lots of short trips in a cool climate.
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Old 07-02-2003, 12:03 PM   #34
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Old 07-02-2003, 12:24 PM   #35
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Thanks Alan.
It'* always a good idea to venture into the unknown with both eyes wide open.
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Old 07-02-2003, 03:06 PM   #36
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OK, after reading those posts I still don't understand why you would get higher combustion temps?? Would someone like to fill me in on this? It doesn't seem to make any sense to me that if you stop hot exhaust air from entering that it would lower combustion temps, hot air lowering combustion temps doesn't make any sense to me.

I think the fact that Zooomer (owner of ZZPerformance) has been doing this on his car for at least a year, along with many other GTP owners, including me, without any problems at all shows that it doesn't hurt anything, besides the fact that it doesn't make any sense why it would.
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Old 07-02-2003, 03:46 PM   #37
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Originally Posted by dbtk2
OK, after reading those posts I still don't understand why you would get higher combustion temps?? Would someone like to fill me in on this? It doesn't seem to make any sense to me that if you stop hot exhaust air from entering that it would lower combustion temps, hot air lowering combustion temps doesn't make any sense to me.

I think the fact that Zooomer (owner of ZZPerformance) has been doing this on his car for at least a year, along with many other GTP owners, including me, without any problems at all shows that it doesn't hurt anything, besides the fact that it doesn't make any sense why it would.
I'm just speaking from my own personal experiences with my OWN EGRless engine! I can tell you that this engine runs way hotter than any other 3800 I've come across! I've got the Cracked LH Exhaust Manifold & Burnt #6 Exhaust Valve to prove it too! This may also be the reason I can safely run a Bosch O2 Sensor w/o any ill effects too.

Actually you're not stopping the Hot Exhaust Gases, you're just redirecting them with the EGR Valve! So therefore, if you have no EGR Valve, the gases have no real place to go except by the Exhaust Valves & Exhaust Manifolds, hence eventually burning the Valves & Cracking the Manifolds! Remember EGR stands for "Exhaust Gases Recirculation"
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Old 07-02-2003, 09:50 PM   #38
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OK, after reading those posts I still don't understand why you would get higher combustion temps?? Would someone like to fill me in on this? It doesn't seem to make any sense to me that if you stop hot exhaust air from entering that it would lower combustion temps, hot air lowering combustion temps doesn't make any sense to me.
Well it probably has something to do with the exhaust gases diluting the oxygen content so the mixture burns at a slightly lower temperature. You know, the old enthalpy triangle, fuel - oxygen - heat.

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Actually you're not stopping the Hot Exhaust Gases, you're just redirecting them with the EGR Valve! So therefore, if you have no EGR Valve, the gases have no real place to go except by the Exhaust Valves & Exhaust Manifolds, hence eventually burning the Valves & Cracking the Manifolds! Remember EGR stands for "Exhaust Gases Recirculation"
But...the Exhaust Gas on our Series II engines recirculates AFTER the exhaust valves from the rear exhaust manifold.
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Old 07-02-2003, 10:36 PM   #39
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I'm just speaking from my own personal experiences with my OWN EGRless engine! I can tell you that this engine runs way hotter than any other 3800 I've come across! I've got the Cracked LH Exhaust Manifold & Burnt #6 Exhaust Valve to prove it too! This may also be the reason I can safely run a Bosch O2 Sensor w/o any ill effects too.

Actually you're not stopping the Hot Exhaust Gases, you're just redirecting them with the EGR Valve! So therefore, if you have no EGR Valve, the gases have no real place to go except by the Exhaust Valves & Exhaust Manifolds, hence eventually burning the Valves & Cracking the Manifolds! Remember EGR stands for "Exhaust Gases Recirculation"
I don't know what is wrong with your egr-less engine, but our '92 Olds 88 ran usually no hotter than 200 degrees, and it was completely stock the whole time we owned it. We had no problems with anything cracking, or burnt exhaust valves or anything, and as I said we sold it with 193,000 miles on it and it ran as good, if not better, than when we bought it with 10,000 on it. My suggestion to you is to run a colder thermostat and your problems should be solved. Maybe a drilled 160.

[/quote]But...the Exhaust Gas on our Series II engines recirculates AFTER the exhaust valves from the rear exhaust manifold.
Quote:

Yes, exactly, so it not passing by the valves doesn't make any sense. Since it exits from the exhaust manifold, it would've already passed through the exhaust valve and into the exhaust manifold. The only problem I can see with removing the EGR is maybe getting a lean condition because the computer is assuming it is getting back some of that unused fuel in the exhaust, but I am pretty sure that doesn't happen, because I don't think the computer is that advanced in it fuel system, and it is the only thing I can halfway understand happening as a negative with EGR blockoff.
Actually you're not stopping the Hot Exhaust Gases, you're just redirecting them with the EGR Valve!
Quote:

I know you aren't stopping the hot exhaust gases, you can't because that is how an engine works, it uses a spark to ignite fuel to make an explosion to push the pistons, then the gasses from this process exit through the exhaust valves. You have to have hot exhaust gasses, because when fuel is ignited it is hot. The EGR valve then takes these hot exhaust gasses from the rear exhaust manifold, and directs it back into the air intake, what good can it do for anything except re-use gas for better gas mileage? If you remove it from the rear exhaust manifold and put a filter on it, it will only be letting in clean air. Unless I am mis-understanding what you are saying, I don't see how this is a problem. You keep saying that EGR "combats heat" and you need to find other ways to combat heat if you remove it. I guess what I don't understand is how it is "combating heat" since basically all it is is heat with exhaust gasses in it. Please explain, I don't understand?!?!?!
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Old 07-03-2003, 12:34 AM   #40
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Quote:
Originally Posted by dbtk2
I don't know what is wrong with your egr-less engine, but our '92 Olds 88 ran usually no hotter than 200 degrees, and it was completely stock the whole time we owned it. We had no problems with anything cracking, or burnt exhaust valves or anything, and as I said we sold it with 193,000 miles on it and it ran as good, if not better, than when we bought it with 10,000 on it. My suggestion to you is to run a colder thermostat and your problems should be solved. Maybe a drilled 160.
I've already solved the heat problem though, by running a drilled 180 (2 - 1/16" holes at 180 degrees apart) & switching from Mobil 1 to Amsoil synthetic 10W30 Oil & Amsoil Super Duty Oil Filter too.
I base my experience from other EGRless 3800'* (including my own). Maybe it'* the combined EGRless 3800 & the varied Temperature up here that causes it then, as I've seen quite a few now going through our GM Shop at work too.
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