from what i have heard from some on here. running no egr on a us ecu will make you run a little lean at mid throttle to about 3/4 throttle. it this true.
running no egr question
- Thread starter Supraboy89
- Start date
Not really "lean" but EGR raises the knock threshhold. The ECU is tuned for the EGR to be there...
I'm thinking timing map is what is different, but I could be wrong...
I'm thinking timing map is what is different, but I could be wrong...
And where does one find a JDM ECU...? I started a thread in the TCCS subforum to discuss this, but it hasn't been approved....that was about 3 days ago, too....*sigh*
Removing the EGR i think is a good idea if you want to run the car hotter under normal conditions witch is favorable because it will run with in temp spec better and revent carbon buildup much better, because after all the EGR is meant to reduce operating temp and prevent NOx (smog). And of course no more crap on your intake vales!
And I agree.. You will need a JDM ECU. I would guess it runs lean because exhaust gases have a lot of unburnt fuel, the best new cars only burn up to ~30% of the fuel in the cylinder.
And I agree.. You will need a JDM ECU. I would guess it runs lean because exhaust gases have a lot of unburnt fuel, the best new cars only burn up to ~30% of the fuel in the cylinder.
NeatOman;1095963 said:
NeatO - If you are going to post in Tech, you really need to know what you're talking about and stop speculating.
Your entire post is full of misinformation.
The EGR reduces combustion cylinder temps to reduce NOx...it also suppresses detonation. Higher cylinder temps are not a good thing...the combustion process is meant to be a burn, not an explosion. High temps will not remove carbon, in fact, carbon can cause hot spots and pre-ignition of a mixture. Carbon is caused by an exhaust restriction, a rich mixture, timing, or oil blow-by...basically incomplete combustion or oil contamination. High temps will not do a thing to help.
Not too sure where you came up with the unburned fuel idea in exhaust gas, but that is pure BS. If a car engine only burned 30% of the fuel in a tank to make power, we all would be in a heck of a lot more trouble MPG wise considering the price of gas...it defies common sense.
From what I know, a JDM ECU has different timing/fuel maps programmed to account for the missing EGR. It's that simple.
Next time you post in Tech, I suggest you think about what you are going to say. This type of crap is getting very, very old.
Jdub, I have never seen you post anything about fuel mileage when you talk about this subject. I would assume the JDM would increase fuel a bit, and thus have slightly less fuel economy.
That's a good question Scott...I don't know how it would affect MPG.
I am sure timing is different. Dean Marcum posted this on the SOGI mailing list a while back:
http://www.supras.com/pipermail/supras_supras.com/2004-February/002466.html
What is interesting is that it looks like timing is advanced on the JDM ECU...with no EGR, that would make pinging more likely. Dean saw this, but he was also running well above stock boost and it was above 4000 RPM where the EGR is cut off on USDM ECUs.
I am sure timing is different. Dean Marcum posted this on the SOGI mailing list a while back:
http://www.supras.com/pipermail/supras_supras.com/2004-February/002466.html
What is interesting is that it looks like timing is advanced on the JDM ECU...with no EGR, that would make pinging more likely. Dean saw this, but he was also running well above stock boost and it was above 4000 RPM where the EGR is cut off on USDM ECUs.
i know everyone here is missing me arent they :naughty: so i guess another way of fixing this suposive lean issue maybe getting a piggy bank system like a apexi safc/II/neo or a map ecu, timing wise a adjustable timing gears might do the trick, oh and btw as for my build its almost finished its going to the machinest in about a week and need to get a oil return line and restrictor for the turbo. 
wish me luck and make your life easy and get the JDM ecu
wish me luck and make your life easy and get the JDM ecu
the reason i asked this question is because with my jdm motor with timing set to 12 i get some pinging at about mid throttle when the motor is already warm. it didnt do that with the us motor. i just figured it was because i wasnt running a egr. i would get a jdm ecu but i need to pass emissions.
Set your timing at 10 deg BDTC...that should help with the mid throttle ping. Might need to back off the boost as well. Concerning emissions, did you have an EGR cooler on the back of the head?
when you say egr cooler do you mean the rectangular bolt on plate or coolant lines running to something else
The rectangular bolt on plate...if it's there, it's a heck of a lot easier to install an EGR to pass emissions.
yeah i installed it on the jdm motor when i put it in. i also installed the egr to. i just block off the vaccume line to keep it shut. and plug it in when i take it to have emissions done. but for some odd reason when it is plugged up when i am driving under normal conditions i get some slight hesitation on excelleration. block it off and no hesitation. it didnt do this with the us motor. all vacc reads the same from us motor to jdm on boost gauge. it just has me puzzled a little? other than that it runs fine
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ForcedTorque;1095990 said:
well I will adress this as jdub has not
EGR in all actuallity helps in increasing gas mileage when the tune accounts for it.
Honda knows this so much so that they tend to run 30% egr at light throttle to do a couple of things.
1. Detonation supresession
2. Decrease pumping losses
3. Effectivly DECREASE the displacement of the engine by the 30% that motor is reinjesting.
on the Honda Insight.
That comes with a 1.0L engine. Decrease the effective displacement by 30% and you are now at a paultry 700cc engine.
The same DOES apply to the supra
3.0L engine that has been tuned with light load/cruise EGR useage in mind and you are talking a 2098 cc engine (2.1L) with pumping losses minimized (using a higher VE).
Remember
Exhaust gases are inert.
jdub;1095999 said:
jdub
check this out
http://www.autospeed.com/cms/A_110577/article.html
those aussies know thier stuff!
and finally
mahle
http://www.mahle.com/C125713200619F8F/CurrentBaseLink/W276SEUW250MARSEN
notice the title of the article.
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figgie;1096994 said:well I will adress this as jdub has not
EGR in all actuallity helps in increasing gas mileage when the tune accounts for it.
Honda knows this so much so that they tend to run 30% egr at light throttle to do a couple of things.
1. Detonation supresession
2. Decrease pumping losses
3. Effectivly DECREASE the displacement of the engine by the 30% that motor is reinjesting.
on the Honda Insight.
That comes with a 1.0L engine. Decrease the effective displacement by 30% and you are now at a paultry 700cc engine.
The same DOES apply to the supra
3.0L engine that has been tuned with light load/cruise EGR useage in mind and you are talking a 2098 cc engine (2.1L) with pumping losses minimized (using a higher VE).
Remember
Exhaust gases are inert.
jdub
check this out
http://www.autospeed.com/cms/A_110577/article.html
those aussies know thier stuff!
and finally
mahle
http://www.mahle.com/C125713200619F8F/CurrentBaseLink/W276SEUW250MARSEN
notice the title of the article.
cool. good info man.
jdub;1097107 said:Damn good info Figgie...confirms a lot of the other aspects of what the EGR does too
we have come full circle!
I am still trying to figure out how the "block EGR" was ever a good idea.
Though I would not use the OEM setup if attempting to do what the company, Mahle, describes. That would require a bigger "pipe" than OEM for sure.