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Discussion Starter · #1 ·
I am considering buying a 7mge crate engine off of ebay that is jdm with block off plates, they say 25-35k miles which sounds like b.s but has anyone bought a jdm engine with a bad experience? I am considering dropping like 600 dollars and would like to hear some input, please point me in the right direction if it is needed (a place to buy a used 7mge or reason not to get an ebay jdm).
I also plan on using my usdm intake and egr accessories if that will keep temps lower (will be using pacesetter 2.25", 295's and and 1 piece tb sized intake FYI). Anyone see a reason too keep the block off plates or jdm intake? Also the engine appears to be mid sump anyone know what cars had them? I remember hearing 91+ jdm cressies had higher comp pistons maybe I can get lucky. Are there any ways to tell the year by looking at a crap pic, assuming it is out of a cressida idk what oil pan they used.
 

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wooooo dylan
get rid of the egr because it puts hot air in the rear of the head resulting in bhg
 

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Discussion Starter · #4 ·
^ If that was the case they would have recalled and redesigned or removed it. It was poor torque values from the factory that caused BHG. I have heard that an egr equiped 7m runs 100 degrees cooler, and it is only engaged at idle. But I am looking for input from people running their engines with egr removed to get their take on it, is yours blocked off? If so is their any benifits you can point out, like cleaner intake, more engine bay space, ect. I am open to opinions and facts. Also would an egr deleted 7m need the jdm ecu for the afr tune?
 

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Discussion Starter · #6 ·
Yea I was, but I am still open to opinions about it. I did realize I polluted my thread asking about imported engines with egr talk lol.. oh well live and learn. And that thread was the one I was thinking of when I said it has temp benefits.
Anyways anyone here have experience with jdm motors?
 

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sorry david but your wrong
look up temp reading for egr on the backside of the head
then look up where the head gaskets tend to blow and you will notice that they are more towards the back!
I have read the post at supramania and do not agree with it
heck me and jake abkmk2 just had this discussion

HE IS GOING 7M NA
the egts are always going to be lower on a NA motor compared to a force inducted motor
I still stand by my post
I have found a a degree difference on my 7m this was temp difference by a few degrees
i tapped a temp probe into the egr
one not blocked off and then one blocked off
now this was 2-3 years ago as i to thought egts would be different but unless your shoving ice cold air into the na motor the egt's will be lower withought it.
mind you this is also a ported head so im flowing some air and i also was running a few degrees on the intake i believe maybe negative because i was trying to achieve my 8k rpm. this is before i knew that you needed a daughterboard in the ecu to change the 6500 redline.

so my advice to you is to lose the egr
gordon (Gofastgeorge) has a 7mge NA and is pushing i believe it was 250hp he has dyno sheets anyways he told me to remove it a really long time ago. but also when you change cams and flow more air through the head it changes EGT's and cooler egts are not always a good thing


also dylan the poor head TQ was also a factor in blowing hg but so is the freaking hot air in the rear of the head. so put two and two together.

also want to lower egts run a higher octane fuel!
this will compensater for the removal and you can run more degrees in timing
get all the power you can out of the NA motor
 

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Discussion Starter · #8 ·
Could you show me a link? And that makes me wonder if their head bolts were torqued properly. Moonpie are you running without egr? If so what are you opinions on the benefits?
 

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i am running without egr
im running high comp pistons
heavly ported head, os valves
and then 15 degrees on the crank at tdc
then a few degrees on the cams
but im running with valve overlap
and the i run 93 octane
headers and then the special ecu

Get rid of it, you can run a higher octane and still achieve lower chamber temps without detonation.
 

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moonpie33, I have to disagree with you on this one. The whole purpose of the EGR is to reduce NOx by REDUCING combustion chamber temps.

Yes, it is forcing hot exhaust gasses into the combustion chamber, but it is also inert gas, meaning it takes up space and doesn't combust. Another one of it's benefits is that it pre-warms the A/F mixture, allowing more energy to be transferred into mechanical movement, rather than heat. It also drastically lengthens the live of the valves (particularly exhaust valves).

And it doesn't heat up the back of the head only, EGR injects into the intake manifold, dispersing evenly among the cylinders.

The ERG system has it's downsides as well, like reduced power (when open), acceleration (when open), etc... but the EGR should only come on at cruise, so you should not notice any difference anyway.

All the cons of the EGR have been solved in modern cars via VVT.
We can now close the exhaust valves a little sooner upon request to "trap" some of the inert exhaust gasses in the cylinder, so the EGR is no longer needed.
 

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though the egr is closed at WOT
and opened at half throttle
yes the egr does transfer heat evenly it is still hot air
somthing we dont want. Now the egr itsle wraps around the M series head.
 

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Bit it's the fact that it delivers hot air, that cools things down in return. And the EGR plumbing will always wrap around the M series head even if you block it off before it exits the head at the rear of the engine.
You know... The ECU accounts for EGR gasses entering the engine under certain driving conditions too. Without a functional EGR system, you won't have an optimum mixture in your combustion chamber, and valve life will be reduced.

I don't think people properly understand the operation of the EGR completely, and just remove it because it's an emissions device. Everyone has this image in their head that emissions devices lug down an engine, and while some may, it's ALL taken account for by the ECU. Removing all emissions devices on a factory ECU won't always net you HP numbers, but give you a warm feeling inside. And again I say most, not all. There are always exceptions.
 

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I'm going to have to agree with Moonpie on this one. The only reason Toyota put the EGR on these engines is to comply with emissions standards in the country the cars are being sold in. That is why in countries that don't require it, they come factory with block off plates (as in JDM engines). They (Toyota) as a company would not add addtional parts (and cost) if they didn't have to. I do know how an EGR system operates and the economy and emissions benefits, but performance-wise there is no benefit to keeping an egr if you can tune without it. They are very well known to carbon up the intake manifold and create excess heat around the #6 cylinder. The JDM block off plates plug it at the back of the head, not at the exit of the cooler, so there is no flow at the back of the head.
 

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Yeah they came with block off plates. That would be the cheaper route if emissions wasn't enforced over there. But the main difference was the JDM ECU mapped for no EGR.
I'm not backing up the EGR system and saying it gives you more power or anything, but USDM engines were tuned with the EGR system in place from the factory.
 

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JDM ECU mapped for no EGR.
I'm not backing up the EGR system and saying it gives you more power or anything, but USDM engines were tuned with the EGR system in place from the factory.
please show proof of this because i do not believe this.
fuel maps would all be the same im talking 86-88 NA and then 87-88 turbo

egr does not give any hp results!
 

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please show proof of this because i do not believe this.
fuel maps would all be the same im talking 86-88 NA and then 87-88 turbo

egr does not give any hp results!
Show you results of what exactly?

How do you know fuel maps would be the same on say... A 6m ECU compared to a 5m?

And I know the EGR renders no HP results... I said that already.
It's for combustion chamber temperture & NOx reduction...
 

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FWIW there are lots of JDM 7M's (no EGR) here in Australia and there's no indication they are less prone to the dreaded BHG than the locally-delivered EGR-equipped versions. I have personally seen a few low-mileage versions blow the gasket not long after being installed.
 
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