I accidently knocked off the vac line to the egr valve and noticed the car ran poorly. Later, i found i some how "melted" my cat converter down. Related maybe? That was after a long drive.
Installed EGR...Interesting Effect on EGT
- Thread starter jdub
- Start date
KILLERMK3 said:
having a vac leak will cause to car to run lean and it may even miss fire. about the converter a lean condition may cause a problem but i have not heard of it mealting one down, ther must have been some other problem running rich for a short time will cause melt down in the converter.
i know im resurrecting an old thread here but it would seem to me that if you remove the egr and keep the usdm ecu, even without a piggyback or standalone system, you should be fine if you run premium all the time with a slight mix of race fuel, right? because jdm engines, at least from what i have heard, in the 80s-90s typically ran on 100 octane fuel. so if you have mostly 93 octane premium fuel mixed with some 110 octane race fuel in small quantities, it should get the octane back up to jdm specs and there should be no detonation without the egr. and another thing, if the recirculated exhaust gases are routed back into the combustion chamber(even though it cools the mixture i can understand that), it is still taking up room in the combustion chamber that COULD have been used otherwise for more fuel, right? so in that case, egr and water/meth injection keep things cool, but you do sacrifice some part-throttle power with egr. am i right? if u haven't noticed, i am an egr hater and im looking for any excuse i can to get rid of it!
No... you've left out the fact that the JDM ecus are specifically coded to run without it on that level of fuel. Without the JDM ecu, you're missing a critical part of the puzzle.
This may be a stupid question but has it been proven that the JDM ecu is tuned differently solely for the fact that it has no EGR, or is it all just assumption? If so who looked into the issue and what exactly is different? I have heard timing maps are different but never seen any proof.
CyFi6 those are some nice looking wheels! what kind are they and what are the offset if u dont mind telling me?
I can say that that I have looked at the 7MGE ECU code and there are separate maps for EGR and EGR-less operation, which can be selected using a resistor in the ECU. Said resistor will also eliminate the EGR output signal.
I do not have a EGR-less 7M-GTE ECU so I cannot say what the differences are, but I would expect to see similar variations as for the GE. The GTE ECU *cannot* be switched between EGR and EGR-less operation like the GE ECU can with a resistor. If anyone can supply a 7M-GTE JDM ECU I would be happy to pull out the code and share it.
I do not have a EGR-less 7M-GTE ECU so I cannot say what the differences are, but I would expect to see similar variations as for the GE. The GTE ECU *cannot* be switched between EGR and EGR-less operation like the GE ECU can with a resistor. If anyone can supply a 7M-GTE JDM ECU I would be happy to pull out the code and share it.
CyFi6;1637357 said:
i'm building my top end and when i pulled my egr it had a vaccum line dangling off it that doesn't appear to go anywhere =S its a motor that has had many idiots such as myself and a previous owner tear it apart in their driveways, so someone probably forgot to hook it up. if anyone were to tell me where the lines from the egr run that would be great. new to the form and trying to re-build a head. my motor has some after market bits and will hopefully push 350 wheel on 15 psi boost rc 550ccs lexus maf and an apexi safc.
http://www.cygnusx1.net/Supra/Library/EPC/291420/catalog.aspx?F=1708&P=3
You have no idea how much these EGR threads amuse me. They're pure gold.
Edit: beaten by 3p. Better pic too!
You have no idea how much these EGR threads amuse me. They're pure gold.
Edit: beaten by 3p. Better pic too!
CyFi6;1637357 said:
I realize this is old, but there are some here that do this proffessionaly and are paid well. Paid well comes with knowing how it works and why. Toyota, as well as others, have publications available on this subject and many others.
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I have my engine rebuilded. Will let you see pics of 15000km egrless operation with stock eudm ecu and E10 fuel.
No problem so far (I think), a bhg due to overheating next to a broken line. I will see if any sign of overheating of piston head due to EGT
I have my engine rebuilded. Will let you see pics of 15000km egrless operation with stock eudm ecu and E10 fuel.
No problem so far (I think), a bhg due to overheating next to a broken line. I will see if any sign of overheating of piston head due to EGT
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