2jz Bottom End 1jz Head

[annoyingrob]

Good pic mate, up-rep

Here are mine:

Bypass pipe length difference


Water outlet difference. Sorry for blurry pic, dodgy camera


Oil feed area of headgaskets. 1J on top, 2J on bottom


1J head, oil feed area


2J head, oil feed area


2J block, oil feed area


1J block, oil feed area



1JZ head with oil feed section welded up, and re-drilled at angle so the 2J feed hole in block is met.


Now, it may not be 100% required to do this as someone has already said they didnt and its running however, if you look at the block areas and the head etc it is highly likely that an oil feed issue will occur without doing this as the high pressure feed is very close to the edge if you do the swap and no changes. I looked at the water jacketing for a while prior to proceeding with the conversion and I couldn't see any reason as to why any other changes might need to occur.

Thats just my $0.02 worth anyway

Ok, this makes a lot more sense now. The 2JZ block has the oil feed closer to the outside of the block, so it doesn't line up quite right with the 1JZ head. I'm still under the impression that with a 1JZ head gasket, it will work fine, but if my 1.5JZ starts leaking, I'll make sure to let you guys know.

[lexsmaz]

Comparing both heads & gaskets, i would say if you didnt weld up the elongated oil feed hole in the head you would have major oil feed leaks ( internally ) if you used a 2jz gasket ... The other way ( maybe ) without welding the head would be to use a 1jz gasket & just drill another oil hole feed in the gasket which lines up with head & block ?, you can see that the 1jz gasket area around the outside of the oil feed hole is elongated already .... I also would think if you used a 1jz gasket without any mods you would have some pretty serious oil starvation problems to the head .....

[The Real Roadrunner]

when you compare gaskets the hole looks close enough to work without mods (but would be better with.

any chance of an overlay of both gaskets and shots from above both blocks ie 90deg to the block?

cheers
linden

[manny]

I removed the head off mine on Sunday but haven't got any pics as yet until I can get a working digital camera.
With my Japanese assembled combo of 1JZ head, 1JZ head gasket and 2JZ bottom end, I can confirm that there is no welding to head or block or drilling to head, gasket or block and despite it having run over 50,000 tough kms (20+psi, 8500rpm redline, 264/264 cams, GT35R), there were no evident oiling issues in any of the cam caps/bearings in the head or any leaks between head gasket mating surfaces.
Imho, there's much more of a chance of the head gasket blowing out between cylinders with the magnitudes of higher cylinder pressure during the normal combustion process or the occasional ping from poor fuel/ tune than the < 100 psi that the oil gallery and mating surface will see in operation.

[Enigma-Penguin]

Hmm I find that very very interesting, can't wait to see those pics. I'm on the tipping point of doing 1.5jz (Tried to buy the one from import bits but missed it ) but I'll probably wuss out and just get another 1j.

[Endless]

Very interesting Manny! Look forward to pics...

Sounds very promising though... something i will definitely be doing down the track if this is the case.

[Wildsupra]

I removed the head off mine on Sunday but haven't got any pics as yet until I can get a working digital camera.
With my Japanese assembled combo of 1JZ head, 1JZ head gasket and 2JZ bottom end, I can confirm that there is no welding to head or block or drilling to head, gasket or block and despite it having run over 50,000 tough kms (20+psi, 8500rpm redline, 264/264 cams, GT35R), there were no evident oiling issues in any of the cam caps/bearings in the head or any leaks between head gasket mating surfaces.
Imho, there's much more of a chance of the head gasket blowing out between cylinders with the magnitudes of higher cylinder pressure during the normal combustion process or the occasional ping from poor fuel/ tune than the < 100 psi that the oil gallery and mating surface will see in operation.

If this is the case it makes me smile
might have to start gettin my 2j bottom end rebuild under way, apparantly my 1j is about to blow.......14:1 AFR's anyone???

Cheers Manny

[big JON]

I removed the head off mine on Sunday but haven't got any pics as yet until I can get a working digital camera.
With my Japanese assembled combo of 1JZ head, 1JZ head gasket and 2JZ bottom end, I can confirm that there is no welding to head or block or drilling to head, gasket or block and despite it having run over 50,000 tough kms (20+psi, 8500rpm redline, 264/264 cams, GT35R), there were no evident oiling issues in any of the cam caps/bearings in the head or any leaks between head gasket mating surfaces.
Imho, there's much more of a chance of the head gasket blowing out between cylinders with the magnitudes of higher cylinder pressure during the normal combustion process or the occasional ping from poor fuel/ tune than the < 100 psi that the oil gallery and mating surface will see in operation.

I do quite like the sound of that too.

I've got a few questions, mostly A70 based:

* Can my 1JZ solid engine mounts be used with the 2JZ block? And will it still fit under the bonnet with the extra height of the 2J?

* What radiator hoses can be used? Am i able to retain the JZA70 1JZ hoses? I've got my name on a set of silicon JZA70 hoses and want to know if they'll fit before spending the money

* Will the stock 380cc injectors be enough to cope with the extra displacement? Or will they need replacing straight up?

* The water pump and hydro setup, the 2J pump is different so what can i do about the hydro setup? I think i read somewhere that the Aristo uses a hydro fan? Is that the go?

* Are there any other compatability issues that i may have missed?

Cheers,
Jon

[annoyingrob]

I do quite like the sound of that too.

I've got a few questions, mostly A70 based:

* Can my 1JZ solid engine mounts be used with the 2JZ block? And will it still fit under the bonnet with the extra height of the 2J?

* What radiator hoses can be used? Am i able to retain the JZA70 1JZ hoses? I've got my name on a set of silicon JZA70 hoses and want to know if they'll fit before spending the money

* Will the stock 380cc injectors be enough to cope with the extra displacement? Or will they need replacing straight up?

* The water pump and hydro setup, the 2J pump is different so what can i do about the hydro setup? I think i read somewhere that the Aristo uses a hydro fan? Is that the go?

* Are there any other compatability issues that i may have missed?

Cheers,
Jon

Yes your solid 1JZ mounts can be used on the 2JZ block. I run solid 1JZ mounts on mine. Yes it will clear the hood still.

Yes you can use JZA70 rad pipes. Again, that's what I use.

380cc injectors won't be enough. Try to find a set of JDM 2JZ 440cc injectors.

Yes the Aristo uses a hydro fan too. If you already have a 1JZ, just put the pump onto the 2JZ block. It fits.

[big JON]

yep, the 1J is already in, so i can use the 1J water pump and still keep the current hydro setup?

That's awesome. Now all i need to find is a 2J bottom end and im laughing!

[Wildsupra]

sweet that answers a few of my questions too
BIG JON i already got the 2jz bottom end, just needs a re ring and freshen up...race ya

Im gunna look at using the 1jz computer and harness and simply slot in the 2jz injectors to compensate for dispacement and see wot happens.

Matty

[annoyingrob]

Im gunna look at using the 1jz computer and harness and simply slot in the 2jz injectors to compensate for dispacement and see wot happens.

Matty

Assuming you're talking about the 440cc injectors (as opposed to 2JZ 550s), that would probably work quite well.

[big JON]

Want to sell it to me Matty? I found one last night for $1700 but i want one cheaper than that to make it viable.

Will the 1J ecu work with the 1.5J conversion?

[Wildsupra]

hehe nup dun wanna sell it
I assume the one you found for 1700 is prolly the first one i found but didnt want for that price hehe
I cant see why the 1jz ecu wont work, there isnt really anything on the 2jz block different as far as wiring goes and by using 2jz injectors that should sort fuel out on lowish boost.

Im just waiting for my 1jz to pop before i swap it over, i woulda thought running at 14:1 afr's for a few months woulda done it hehe ahh well the wait continues...to the drags again on higher boost

Matty

[SaabG]

Is there any way to view the pictures on page 4? I'm about to start my 1.5j conversion and I believe viewing these pictures would be very helpful to my cause.