Frankenstein engines. 2JZGE/GTE - 1.5JZ

[iwantablackrz]

Hi guys,

I posted this on the US Supraforums but they just told me to go NA-T which although might be a great idea in the US of A I think there are better options especially when I have half a built engine sitting here but then again we all know how much the Americans love their 2J NA-T's...

Sorry, I digress.

I figure you guys might have a good idea on some of the technical stuff relating to what I may be doing so here goes....

As some of you may know I have a JZA80 NA Supra. It's putting out decent power but like the story always goes I want more power. More than double actually. It'll be built with response over all out power as I still want to keep my NA ethos.

I was originally toying with bolting a 1JZ head to my 2JZGE bottom end for a 1.5JZ. Obviously the little turbo's on the 1JZ would run out of puff up top on a 3 litre so I was/am planning on bolting on a GT35R (.82 rear) straight up. It's not a huge turbo but I want an emphasis on response rather than all out power although I'm still aiming for what I believe to be an acheivable 320-340'ish rwkw.

So I was looking around at 1JZ heads when a built (re cut valve seats - new valve guides, crower springs and titanium retainers, ceramic coated valves and port/ polished) 2JZGTE head came up for a steal. Without any research I bought it on the thinking that if it doesn't work I can always get my money back anyway.

So, I suppose what I'm really wanting to know is can (or has) a 2JZGTE head bolted up to a 2JZGE bottom end. How does it go? What are the weakness's? What ancilleries will need replacing? Do I need a GTE waterpump or will the GE pump suffice? (I believe I need the GTE oil pump) What compression would I be looking at with an stock (new) HG? Will a 2JZGTE ECU/Loom work or should I just go with a full aftermarket ECU replacement (with GTE loom)? I'll be going straight to the GT35R so I'm aware the NA fuel system will need to be beefed up and will be upgrading both the pump and the injectors with a 2JZGTE intake plenum and fuel rail.

Has anyone done this? I know in theory everything bolts right up so it's just working out whether everything will work the way I want it too. I'm kind of planning not to touch the 2JZGE bottom end and only lowering the compression with a HG. That is if this can be done.

Opinions? Thoughts?

Any constructive help, thoughts, suggestions are welcome.

Dave


PS. I'm aware that my drivetrain will be in need of beefing up also.

[H1TMAN]

I believe that the 2jzgte head will bolt strait up, you will need a larger headgasket to lower compression.
What pistons are in the engine right now? You would need some that are made for high power turbo setups. You should get a aftermarket ecu if you want to be toying around with huge power.

Really a 2jz head is a lot better then the 1j, all in all if you are after bucketloads of power-
Buy a 2J power kit (they include pistons, rings ect) that are good for 1000hp plus, get better cams, choose between twin or high power single turbo, get a titanium exhaust and and parachute.

Because to me it sounds like you want a lot of power, and thats what I would do... minus the parachute.

[1JZ-Rolla]

^^^^ Is he for real?

[SeptemberSquall]

who, parachute man or the o.p.? can I be the first one to say get a turbo jza80 to start with and build from there? two of the most expensive and disappointing roads to walk in a build are "i'll just use this (engine/gearbox/car) cause it's what i've got" and "look at me, i'm doing my own thing".

[DrNick]

Hey Dave, With regard to the GTE head on the existing block, yes anything is possible. But its not feasible. You have to change so much stuff around that you would be better off just starting with the entire engine.

Yep you can decompress a little bit with a head gasket. A stock TT HG (1.3 mm) gives you about 9.2:1 compression ratio if you use the existing NA pistons. Your results may vary depending on how much the head has been decked to make it flat.

I'm sure you've seen the 10 million "na-t its not worth the cost" threads on supraforums so I wont drag that up. Its a good route to take if you are technically minded and want a project, if you are just looking for a power upgrade (and also if you are paying a workshop to do it) then transplant a GTE engine in and get it over with. I can see that you want something a bit different from everyone else (which is a plus) so I think the first option is more likely to be the one you are interested in though Pity you're not in WA or I'd be happy to show you what you need for that project (Meanwhile clubna-t.com is good for general information).

[1JZ-Rolla]

who, parachute man or the o.p.?

'chute man.....

how do you jump to recommendations of titanium exhausts, "2JZ power kits" (WTF is that anyway, and who makes them? can I get it in my cornflakes box?), "better cams", and a thicker head gasket?.

Give the guy some qualified and researched information, or as SeptSqualldude said, start with the car you are aiming for in the first place

And the yanks might not be so silly.... NA-T setups can be rediculously cost effective, have super response, and good reliability with realistic power figures in excess of 300wkw with good fuel and a reasonable ECU tuned well. Toyota didn't do such a bad job from the factory, with the GE motor being quite over-engineered....

But its still not a 2JZGTE

[iwantablackrz]

Thanks so much for your input guys.

SeptemberSquall your suggestion is certainly valid! Haha! It's not like I'm looking to buy a Supra though and what I do have I've put a lot of money into it that simply can't be transferred to a new (turbo) body. Paint etc. I'll be the first to admit aswell that there is a certain personal attachment I have to my car and as much as the logical choice is to sell up and start with anew it's something I'm just not prepared to do. I also know that the car I have is pretty mint and well looked after too.

I was planning on using the stock GE pistons and one of the reasons for me wanting to maintain the GE bottom end was that the engine wouldn't have be removed. As I plan on doing a lot of the work myself in theory (which is 101) it seemed like a pretty straightforward arrangement with just simply bolting off and swapping heads, a few ancilleries and paying for someone to do the wiring/tuning. Perhaps I'll need to find a turboless 2JZGTE somewhere instead.

1JZ-Rolla, I really don't want to do NA-T. Personally and on these shores all the NA-T's that I know never seem to run or perform like their 2JZGTE equals. I know it's not the case with all of them and I know it's a very popular thing in the states but I'm just not 100% sold on the idea. I also have a built 2JZGTE head sitting around that looks like it'll be a bucket load of fun.

[ed]

man, use a std gasket, take the added compression of the na pistons, add a fatter intake cam to drop the dynamic compression ratio ($40 per lobe weld grind @ waggot, and non intference pistons = heaps of scope for lift and duration) go your gt35, rev to 7.5k, shit your pants

[iwantablackrz]

man, use a std gasket, take the added compression of the na pistons, add a fatter intake cam to drop the dynamic compression ratio ($40 per lobe weld grind @ waggot, and non intference pistons = heaps of scope for lift and duration) go your gt35, rev to 7.5k, shit your pants

Haha! I'm hoping I'm crapping my pants because it's awesome and not because it went bang?
That's what I'm more or less hoping to do (the car being awesome and not blowing up). I should get some photo's of the head up but it will need some cams. I was thinking 264 which is pretty mild really but I'm not sure massive cams are needed. The car the head came out of was a built 2JZ Soarer and I know it used 272's but then I'm not aiming for the drag style performance that he had.

[H1TMAN]

'chute man.....

how do you jump to recommendations of titanium exhausts, "2JZ power kits" (WTF is that anyway, and who makes them? can I get it in my cornflakes box?), "better cams", and a thicker head gasket?.

I was joking about the chute, Just seems like his after a whole lot of power. Yes you can buy power kits. Just like a stroker kit for the 2j only the power contains everything bar the block itself pretty much, cant find the link but they do cost around 9k I believe.
Titanium exhausts are used for high power setups, I know quite a few Subaru STI's with them. I could carry the full length exhaust system in one hand with ease, great for weight reduction just damn expensive.
Bigger head gasket I was not so sure of, but my friend did somthing along those lines with his XT falcon when he got a typhoon turbo kit for it (cant quite remember).

Sorry didn't mean to give bad advice

[1JZ.747]

anyone comtemplating putting a titanium exhaust on a car with standard ge pistons would be considered a clown. there are far cheaper weight loss things to do on a car.

if it were me i would pull the bottom end out, put s set of forged pistons in it whilst eh dollar is good. standard head gasket and bolt the gte head on.

[Pimpin_1JZ]

Yep, 1JZ.747 is on the money. The only difference (in bottom ends) between the GE and GTE are the pistions and the oil squirters. Your compression ration may differ if you use the standard pistons which are fine but you will have more drivability off boost, but you just won't be able to run as much as you could with GTE pistons. But there are plenty of big NA-T setups going around to show that the pistons are not needed as such.

And titanium exhausts? You can make plenty power with normal exhausts even more than your mates STI is putting out.

[iwantablackrz]

Cheers guys. I plan on using the GE pistons and using a GTE's 1.3 headgasket to lower the compression enough to be able to safely dial in some boost. I'll need to do some measurements to find out how much as been shaved of my head and work out what sort of compression I'll be looking at but as mentioned the NA-T guys in the states seem to have no compression issues with a set up like this. I'll be running slightly higher comp off boost than a stock GTE but if anything (as long as it's safe) it suits what I want anyway as I do want something that is pretty responsive and have the low end driveability.

To answer some of my original questions does anybody knows what sort of ancilleries I'll be needing to obtain? Oil pump? water pump? etc.
Does anyone know of anyone who has mated a GE bottom end to a GTE head?

[Pimpin_1JZ]

From what I understand you can use everything the same.

[H1TMAN]

And titanium exhausts? You can make plenty power with normal exhausts even more than your mates STI is putting out.

You sure can, but when someone wants minimum weight thats what they do, It puts out somthing crazy like 615rwkw.