Interesting discussion. Re-reading post #19 shows a quote supposedly lifted verbatim from the toyo tech manual by Jetjock which states that an inop EGR will cause severe detonation. With all due respect, were these engineers wrong or am I misunderstanding these latest posts?
7MGTE egr or no egr
- Thread starter IndigoMKII
- Start date
Supposedly?
http://tinyurl.com/4ta5g
Technical article #61. Pay particular attention to pages 1 and 5.
It's doubtful "serious" detonation will occur. It *can* though. In my experience having the car instrumented sans EGR mild detonation does under certain part throttle conditions. Sure, the knock control system steps in but is that how you really want to operate your car?
Google "egr and detonation". Nobody who understands how engines work needs to be told this by Toyota or anyone else. Why people continue to argue what is such common knowledge is beyond me.
All that said it can be avoided by simply running more octane. You'll still be spewing NOx and as such should have your car seized, crushed, and melted down for tuna cans but that's an argument for another time...
http://tinyurl.com/4ta5g
Technical article #61. Pay particular attention to pages 1 and 5.
It's doubtful "serious" detonation will occur. It *can* though. In my experience having the car instrumented sans EGR mild detonation does under certain part throttle conditions. Sure, the knock control system steps in but is that how you really want to operate your car?
Google "egr and detonation". Nobody who understands how engines work needs to be told this by Toyota or anyone else. Why people continue to argue what is such common knowledge is beyond me.
All that said it can be avoided by simply running more octane. You'll still be spewing NOx and as such should have your car seized, crushed, and melted down for tuna cans but that's an argument for another time...
Your point about pollution is well taken. My problem is I built a JDM engine which came to me without the EGR system and its in the car and runs well (although has not been to a shop with tools to check state of tune). I'm not sure if I can retrofit the old EGR parts from the na engine without pulling the engine back out and just want to be sure its safe to run as is. How difficult is it to ad the EGR in the car? PS: sorry about the "supposedly" but so much contrary information has been related on this thread its hard to know what to trust. I do have a "tuner" shop in my area that has one partner who has built and raced several Supras, so I'll try to collect enough funds to let him run basic testing, but in the meantime don't want to frag an engine cause I was dumb enough to omit the EGR.
Did they send you the JDM ECU when you got the engine? If so you're good to go, as the JDM ECU's were programmed without an EGR system being installed on the engine in the first place. As for retrofitting an EGR to your existing engine, it's not very expensive to do so but some components can be a cast iron bitch to put on with the engine installed, the EGR cooler for example.
The ECU and harness that came with my engine were for an 89 or newer car. My car is an 87 so I bought a turbo USA harness and the ECU was probably USA as well, although I have been unable to find any clear method of identifying ECU's by numbers. I now have 3, the original 87 na/automatic, the JDM unit with the wrong plugs for my early harness and the one I bought and am using which is for turbo/automatic (although I have converted to R154) and is most likely USA. Would it be possible to install EGR system in other than stock location?
What ECU part number do you have? Post 89 GTE A/Ts in the US were 89661-14270 / 271 / 460 (excluding California).
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Does anyone have a list of ECU's by application, or at least what would be correct # for JDM 1987 turbo vs: US 1987 turbo? Also, anyone got the JDM unit for sale or swap? (I will also post in parts for sale/wanted)
Well it seems I never responded to my thread.. And sorry for making such a horrid thread topic at that. I decided to go with my egr but I cannot find charcoal canister and holding items for the charcoal canister and the BVSV. My BVSV has broken tips like most that I have seen. I don't have emissions where I live but I would enjoy the 'least possible chance' for detonation. Will I need the BVSV and the charcoal canister for my EGR to properly help prevent it? I do have the other pieces for it like vacuum manifold, EGR valve, EGR cooler plate and the EGR vacuum modulator along with the EGR VSV.
Evap system is a different system entirely. It traps gas vapors and releases them into the engine once the engine is warm, and it also keeps 2psi of pressure in the gas tank.
To conclude my post going egrless with an adjustable resistor, it has worked out great. Fuel mixture hasnt ran lean yet and after cleaning intake manifold from 23 years of soot from exhaust, it purrs like cat. Which in comparison to before, it was more like a sick cat
Tony;1742501 said:
It can get nasty in there. I have seen a few where the carbon was thick enough, the valve wouldn't set all the way closed. Not common, but it happens.
Hi all,
I've gone EGRless since 15000km (about 9320 miles).
I've didn't made any mod except:
- silicon hose (the engine temp is cooler than before)
- runing Unleaded 95 + 10% ethanol (called SP95-E10 here in France).
I never get any ECU Fault Code, and it's runing really fine, except a rough idle with missfire. I think my ignitions spark are good to replacement, and maybe my ignition timing is not well set, but I don't have a strobelight.
I think it's good for me.
I've gone EGRless since 15000km (about 9320 miles).
I've didn't made any mod except:
- silicon hose (the engine temp is cooler than before)
- runing Unleaded 95 + 10% ethanol (called SP95-E10 here in France).
I never get any ECU Fault Code, and it's runing really fine, except a rough idle with missfire. I think my ignitions spark are good to replacement, and maybe my ignition timing is not well set, but I don't have a strobelight.
I think it's good for me.
Rollus;1811910 said:
thats great info, i still plan on going erg less in my car once its back together, but I'm still very curious as to how everything looks under the head. after my build i will be running a lot of test on egts,cylinder temps and overall health of the motor, i just wanna put down some hard evidence of the pros and cons of running without out the egr system. i know a lot of guys just choose to leave what works alone but a lot of people like the cleaner look or have acquired a car that already had if removed. I'm not out to prove anyone wrong, and I'm sure the only person ill prove wrong is myself.
nofx230;1812021 said:
Hard evidence has been provided, higher EGT's and it'll run lean at cruise/slight loads because the EGR is not recirculating the gases back into the cylinder. This is not a myth but a fact.
nofx230;1812021 said:
Haha. You have hard evidence. You have scientific proof. I'm not sure what else you are looking for... ?
If you choose to take it out or not run EGR or whatever, just be sure to use a JDM ECU or run a piggyback so you dont fry your engine...
IndigoMKII;1812323 said:
This never clicked for me before. I get why it would run lean.. but if it runs lean at slight loads and cruise.. then wouldn't you get better gas mileage without an egr, as opposed to with one?
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I have about 20% more gas mileage since I've removed EGR.
I should have a look to piston heads when my headgasket will blow out, but it don't want from now
Maybee my spark plugs can tell me some things...
I should have a look to piston heads when my headgasket will blow out, but it don't want from now
Maybee my spark plugs can tell me some things...
Backlash2032;1812338 said:
You would think that running lean would give you better gas mileage but on a properly functioning egr system it won't pull as much timing due to seeing detonation from the lean condition.