GISguy

I've been searching the threads and haven't found much of a straight answer. I was wondering if it's possible to put a USDM 2JZ-GTE head onto a 1JZ-GTE block and thus retain an EGR system and pass smog? If so, would I have to use a 2JZ-GTE USDM ECU?

GISguy

Actually, this might sound stupid, but would a GE head work too? Could I pull the head from my stock 2JZ-GE and put it on the 1JZ-GTE, since its plumbed with EGR?

Or would it be easier to plumb EGR into a 1JZ-GTE?

One thing to note is that I'm running stock exhaust. It has two 3-way cats. Would I pass anyway? Or would it still not lower NoX enough?

Ali SC3

iTrader: (10)

the EGR cooler and passages are on the cylinder head, so that would probably work if you use a USDM ge or gte head. even if it didn't somehow it would all look like it was there and working anyways, that is all you really need you can generally have good numbers on the roller even without an egr system working.

My first EGR delete on a 2jzge head I simply unbolted that pipe that goes from the EGR to the lower intake runner, slipped a block off plate with RTV on both sides (if not you get a vacuum and exhaust leak) and bolted it back down. its pretty impossible to tell that its not actually flowing anything, but it does cause the check light to go off, but a resistor on the egr temp probe takes care of the light. so it looks like its there but it really isn't flowing. with a JDM ecu the check engine light does not go off, only with the US ecu.

if you want the EGR to actually function though you will need a USDM ecu so pretty much you will have to run a USDM 2jzgte ecu or a standalone that can control it.

you could really just also bolt on all the stuff to a JDM head but having a 1jz there are no egr parts to bolt on you would have to custom fabricate some pieces and use 2jzgte parts in the mix.
if you had a 2jz JDM head sure it doesnt have the egr cooler on the rear of the head so exhaust wont actually flow through it, but someone would have to know that and squeeze behind the firewall to notice that there is no egr cooler, and I think there are only a handfull of people on this forum that could actually tell a JDM head from a USDM head once installed with all the accessories. so if your plan is to install it and block it anyways, you don't need a USDM head for that necessarily, just install all the USDM pieces it and its already blocked.

generally no ones pulling off your lower runner to see if the hole in the head is milled out of not, but yeah if you wanted to do it right USDM head and the associated EGR stuff, and also the USDM lower runner has the hole milled out on it, which you could do to a JDM one yourself I guess.

it actually doesn't matter if you use GE or GTE EGR wise except the GTE would be better for the front facing intake and being able to run twin turbos if you want like on your 1jz. also the US 2jzgte ecu does not respond the kindest to na-t setups so going with a 2jzgte head and using stock twins would be your best bet. EGR parts are harder to find for a gte though than a GE they are practically everywhere. so it really depends on what you want.

You can use a 2jzge head and have working egr, you can use a 2jagte head and have working egr.
you can fabricate parts for you current 1jz that look like you have a working egr.

most of the SC's came with 2x 3 way cats, so if your 1jz has 2 then you are good, they simply count them.
I used to have 1 on the midpipe, but they said I needed 2 and now I have a midpipe with 2 cats on it (single turbo downpipe has no cats usually), and haven't has an issue since that.

the sticker on the hood says how many cats and o2 sensors the car came with, its usually 2 cats and 2 o2 sensors. the JDM ecu only uses 1 o2 sensor, so one time I had to go back and install my wideband into a spare spot to count as my second o2 sensor, really dumb but now they count 2 and its all good, so the wideband stays in permanently now, or at least the o2 sensor for it.

KahnBB6

iTrader: (5)

^^ That covers a LOT. I can only add a couple of things to this:

-Yes, USDM 2JZGTE EGR parts are getting harder to find. The valve itself may or may not still be available from Toyota but is sold aftermarket (reman?) by Airtex/Wells. The metal pipe that connects the valve to the head is discontinued. The pipe gaskets are available. The EGR VSV part is (unbelievably) discontinued by Toyota and there is currently no aftermarket VSV available. US 2JZ-GE nonturbo EGR parts are indeed readily available.

-By the book emissions compliance also requires an EVAP VSV and Charcoal canister from a USDM 2JZGTE. You'd need a GTE OBD1 or OBD2 ECU as well.

-At least in Cali, they do a full EGR function test for any vehicles that were supposed to be equipped with it or any USDM engine you've legally swapped in. Obviously not every locale does this after verifying that you have the components present.

But in reality, it's draconian visual inspection compliance in California or any locale that goes to the same lengths that would make going all USDM EGR 2JZGTE fully necessary regardless of how well or poorly your tailpipe numbers come out.

Also, usually a 1.5JZ means taking a cheap 1JZGTE head, turbos and electronics and installing them onto a 2JZ-GE block. For mid-96+ it only requires an oil feed and oil return tap. For 92-95 and early 96 it requires a 96+ oil pump change for the crank-sensor provision. Starting out with a 1JZ-GTE and switching to a USDM 2JZGTE EGR head seems like a lot more added expense just to avoid the oil feed tap, return tap and possibly an oil pump change in addition to the drop in displacement.

Believe me, I also wish there were an easier way to switch a GTE over to by-the-book emissions compliance but if visual inspections are not inflexible where you are you can probably set the engine up to put out acceptable tailpipe numbers very easily.

Ali SC3

iTrader: (10)

Kahn brought up some good points, at the end of the day if I was you I would not do all that work to save the 1jz bottom end and end up with a 2.5L reverse 1.5jz, taking apart 2 good motors, and then the 1j jarness is useless cause you need to use a 2j ecu to actually control egr.

What I would do is sell the 1jz swap as is, and find a stock 2jzge swap bolt that in and na-t it. then you get the egr and everything you are looking for, and the larger displacement.
as Kahn said it only needs a oil tap, return and for na-t obviously a single turbo setup. your funds from selling a 1jz swap with a harness that plugs in should cover most of it.

I would't take off a 1jz head for egr, you may be the first person to ever do that. The 1jz bottom end is what you are normally trying to get rid of, so just sell that swap and get yourself a usdm 2jzge motor, or if you can find the full usdm gte swap (be prepared to fork over an arm and a leg), then of course that would work as well but you will end up spending even more on the 2jzgte harness, whereas the 2jzge harness is just plug and play on our cars. NA-t!!!!

GISguy

I see. Thanks a bunch, Ali. That was very informative.

So would a non-VVTi 2JZ-GTE USDM ECU be able to control a non-VVTi 1JZ-GTE then? So if I were to have a shop drill an exhaust output and make some brackets to hold the 2JZ-GE EGR hardware (cooler, pump, pipes), and then take the 2JZ-GTE ECU and make a harness/adapter from my stock 2JZ-GE harness, it would work? Assuming the 1JZ-GTE ECU doesn't have any EGR functionaliy in it.

GISguy

Are the 2JZ-GTE EGR parts different from the 2JZ-GE parts? Also, does the 1JZ-GTE ECU support EGR or would I have to buy a 2JZ-GTE ECU? (and somehow wire it in)

Ali SC3

iTrader: (10)

Yes a 2jzgte ecu can run a 1jzgte engine but you need to buy an expensive patch harness to make it plug and play with your 1jz harness, or you need to completely rewire your 1jz harnesses ecu plugs to work with the 2jz ecu, how good are you at wiring?

the 1jz ecu and engine do not have egr. period. nada. nope.

the 2jzge egr only bolts on the 2jzge head and stock intake, it wont even come close to fitting on your 1jz with a front facing intake, thats why I said completely custom and you would be better off using 2jzgte egr parts to start from as the 2jzgte has a front intake at the least, still it wont bolt on you will have to do fab for the egr metal pipes at the least and on the lower runner but then the 2jzgte usdm egr parts are like unicorns to find some of the parts, see what kahn said above.

you cannot do anything to your 1jz to make it have a "working" egr without a very involved amount of machine work with the head removed, and thats not only cost prohibitive but no one would actually do that, its a blessing egr is deleted on those factory. you can only make it appear from the front like it had it but being a 1jz its sort of a red flag to anyone that knows toyota's, but most people don't, I wouldn't walk in hoping to get a bar like that.

this is why I suggested selling your whole 1jz engine and harness, without destroying it, and just getting a 2jzge harness and motor for like $500-$800 used prices will vary also. you can plug a 2jzgte ecu into it then, be able to do the tt ecu mod, have working egr, and all that ja

unless you pay more for a patch harness that takes no cutting, you will be messing up your expensive 1jz harness, so either way it costs $$ to do it that way.


vastly different shapes of all the pieces. they have the same types of pieces, but they look different and have different routing for everything.

to get a wroking egr on a 1jz block, what you are proposing is changing every single part of the entirety of the setup and the worst part is you will end up with 2.5L still after spending an insane amount of money doing custom stuff and harness work to fit a 2jz head, ecu, wire it up, all the stuff said above.

the most reasonable route to go would be to buy a used GE motor and harness, drop it in, na-t it, has egr, no harness work, no custom stuff, but you will have to live with the stock intake.
or the next reasonable thing to do would be to swap a USDM 2jzgte head on there and 2jzgte swap harness and find all the USDM egr parts, but thats $$ and time.
ultimately it comes down to preference but I wouldn't replace every part but the block just for egr, at that point just sell it and buy the motor you need, a USDM 2jzgte would actually make more sense then.


when you said your 2jzge, are you saying you have a 2jzge lying around, your stock one?
just use that whole engine then, you don't even have to find one!!

KahnBB6

iTrader: (5)

^^ Again, extremely thorough explanations of the pros and cons from Ali.

GISguy, being in California I have been collecting EGR parts for a USDM 2JZGTE swap. This includes all the parts mentioned above (some, including the crucial VSV solenoid are only available used now), the USDM cylinder head, USDM GTE ECU, USDM upper intake manifold, USDM throttle body, a custom wiring harness, etc. It can be done but without having several thousand to drop on a mostly complete USDM GTE long block when one shows up on SupraForums (which will always be missing lots of parts btw) you will need to be patient and collect all the parts piecemeal.

I'm in agreement with Ali that you should use your original 2JZ-GE engine if you still have it. Other than the oil feed line needing to be routed from the oil filter side of the block (with an IS300 "Union" bolt) and by using a thicker head gasket you can almost identically convert a GE block to a USDM GTE with EGR. With a LOT of parts.

But I'd like to ask, are you required by law to retain EGR where you are registered? What kind of visual inspection are you subject to?

*Edit: Even with my question to you, unless your visual inspection will be a difficult hurdle, Ali's suggestions for using a USDM 2JZ-GE NA-T setup which retains the GE style EGR function can probably do about the same thing at the tailpipe (with both cats retained).

Now the only thing I am not clear on with an NA-T setup and which I have to defer to Ali SC3 about is the GE EGR control when switching from a USDM 2JZ-GE non-vvt ECU to a 2JZGTE ECU. I have to assume that a USDM OBD1 2JZGTE ECU is what you'd need since EGR control isn't part of a JDM Aristo 2JZGTE ECU's programming.... but with the USDM GTE ECU even if the crank sensor signal can be re-rigged to key off of the GE distributor you'll also need to wire for low-impedence 550cc injectors and a resistor pack (correct, Ali?). If all of that sounds right it's very similar to the standard TT ECU mod with just a few more wiring steps.

I don't want to overcomplicate what is already a complicated explanation of choices available but I think that's a good one to cover if EGR function on a reliable NA-T setup is another possible alternative for you. If VA is nearly as strict as Cali, well... then the full USDM GTE conversion route is probably what you'd need to do.

GISguy

Thanks for the advice, guys.

I might actually be moving down to a county without emissions, so this may all be a moot point. Are there any specific turbo kits or anything recommended to make NA-Ting easier, rather than having to custom-measure piping and whatnot?

I have an extra 1JZ-GTE around and a 2JZ-GE currently in my car. If I don't end up moving, I'll just sell the 1JZ to someone else and use the funds for NA-T or something.

KahnBB6

iTrader: (5)

^^ Ali's thread detailing how to wire in an inexpensive Aristo 2JZGTE ECU with your existing 2JZ-GE engine is definitely one of the best budget solutions for a smooth and reliable engine that understands boost. Your GE ECU cannot read boost and an Aristo GTE ECU will be far cheaper than an aftermarket ECU solution.

I have seen premade piping kits available before. Try seeing if Driftmotion or Boostlogic have SC300 specific intercooler pipes available in their catalogs. Other than that you'll find a lot of NA-T kits for the GE engine that take the guesswork out of the very basics like a manifold, basic turbo, BOV, oil lines, etc.

As for moving to a non-emissions county, that would certainly take the pressure off. You can still have generally semi-clean emissions with a simpler single cat system and not sacrifice horsepower. Also, (and be forewarned that this isn't in any way backed by hard evidence) it's been theorized that the 1JZ-GTE VVT-i (1996+) is one of the cleaner emitting JZ turbo engines in stock form. No one has ever definitively posted what kind of emission numbers they put out with a US-spec catalytic convertor but the inclusion of VVT-i and much improved efficiency over the older twin turbo 1JZ probably eliminate the need for EGR the same way the USDM 1998-2005 2JZ-GE VVT-i engines dropped EGR because variable valve timing was able to produce the same or better emission numbers on its own.

Again, no one with a 1JZ VVT-i has posted emission numbers for comparison but in theory it should be much cleaner than a non-EGR non-VVT factory GTE engine from Japan. Clean enough for a US emissions test for your year car is anyone's guess, plus even though it can look "like a stock factory engine" it's still might fail a visual inspection if someone knows what they're looking at depending on how they do things where you live.

mikef

iTrader: (3)

As long as you have your cats on and a good working O2 sensor you will pass federal emissions. for me I dont let anyone drive my car so why would I let a stranger get behind the wheel at a testing station, just keep it registered in a none emissions state. I know cali is to much of a pain.

Ali SC3

iTrader: (10)

My car actually went through emissions in VA when it was na-t you just have to have all thr right components on there generally speaking.
ge egr control and gte egr control are the same ecu wise and wiring wise, there is a 2 wire temp probe that tells the ecu what the exhuast temp is so it knows its working, and there is a 2 wire vsv that modulates the EGR which is controlled by the ecu. toyota uses a standard system for setting up egr but the shapes of the pipes and routing of vacuum hoses vary due to the intake position, on a jz its always starts behind the lower runner by the firewall and then ends up on the intake manifold.
so egr working when using a USDM gte ecu is actually plug and play, now will the temps seen on an na-t always keep the gte ecu happy, not quite sure but you can always do the resistor on the temp probe and the ecu stays happy and it will still work more or less.

the problem is though is that the usdm ecu does not seem to run the na-t properly, well at least the obd2 ecu. the obd1 ecu might work better and run egr if you have a 95 or older car, but no one has tried the obd1 ecu cause people have been looking for obd2 plugin for 96+.
The Jdm ecu which runs the car well has no egr control, but it also wont set off any lights if you are 95 or older its not a huge issue for some.

injectors are plug and play when using a 2jzge harness.
All toyota ecu's need to see a high impedance injector including GE and GTE.
so a GTE had low impedance injectors and a resistor pack on its harness to make the ecu think they are high impedance, and.. A GE just has high impedance injectors with no resistor pack on it so the ecu is happy plug and play with the right size high impedance injectors.

if you have like an aristo non vvti 2jzgte they come with no resistor pack and high impedance 440cc injectors, and later models like the 1jz vvti are the same with high impedance injectors, very similar to the 2jzge. the USDM 2jzgte's and the non vvti 1jz were the ones older motors the did the resistor pack thing so they could use low impedance injectors on a ecu that wants high impedance. they do this not only on our cars but across all the toyota model lines.

its actually more desirable to have the 2jzge type fuel rail and injectors because factory it uses a top feed high impedance setup with a rail as large as a gte. there are tons more injector options for this type of setup. on a gte you have to get an aftermarket top feed rail and usually a aftermarket fuel pressure regulator if you can't score the side feed injectors which are getting harder to find.

The distributor already puts out the exact same signals as a 2jzgte ecu plug and play, there is no need to mess with that, literally to put a gte ecu on a 2jzge harness you just need to upgrade the ignitor and connect 6 wires together at the ecu for the extra 5 gte ignition channels to the stock ignition wire, its so easy its actually weird to explain it in such detail sometimes.
you install your injectors, your map sensor ant IAT like you would on a standalone anyways.
then you pretty much have a well running turbo car if you used the JDM ecu, if you used the USDM ecu then well you will need some luck, which is why this whole egr thing is a bust anyways, cause what good is a fully functioning egr at any cost if your car runs terrible on the ecu that runs the egr.

its a tough choice, maybe if we knew more info like the year of the car and stuff like that it would be helpful.

the just use the jdm ecu and na-t it and rip off the egr. na-t has been a bolt on affair for quite a while now except for intercooler piping, and you have to do that with a gte swap normally unless you use the stock sidemount but those are restrictive. our cars have so much space its easy to cut and clamp together a universal piping kit. you can even get it welded onc eyou have it mocked up but mine have been clamped for years now and doing fine.