1UZ vs. 3UZ Mix Block? (Searched)

The 1UZFE EGR Delete Kit is available for sale here.

rocked

New Member
Ok, from what i've read and seen, the 1uz has allot more meat between the sleeves. So wouldn't the best of both worlds be a 98+ VVTi 1UZ with a set of 3UZ Heads Ported for a big forged induction setup?

Also what does the oiling system look like for the 1UZ bottom vs. the 3uz. The 3UZ looks to be like it was designed from the 1U straight for a dry sumped setup IE In the gt500 cars. Is the oiling system on the bottom end the same on 98+ 1uz?

From what I can see, the 3uz Doesn't look like it has advtages for big forced induction and looks to me like it needs to be resleeved and a new set of pistons due to the iron coating? Also, I'd probably block off the VVTi because I have no need for it, so would it be more beneficial to just run a set of 1uz heads or is there that big of a difference to work with the 3uz setup. I hear the valves are bigger and I'm looking to rev to 10k and boost with something in the ball park of a 91-101mm.

Other than that the 1u setup looks pretty bullett proof at 4.0L, and they're readily available.

Am I correct so far or incorrect, someone let me know.
 
If you're going for the big gold, you want the big motor. The 2uz-fe iron block will spin up the large turbo, especially with on of these cranks punching it out to 5.65L... : )

crankshaft1.jpg
 
right but the question is, iron block is 80lbs heavier...2uz 2bolt mains, the v6 vq35 nissans are making 1500+ easily, no rocked block, at 3.5L...big displacement is great, but rods, pistons drop the motor in, forget it..

2U block is great, but 2bolt mains, all require mods, the 1uz looks to be great, i don't mind the 4.0L I can rev the piss out of it kinda like a 2jz, but without the problems of displacement. If I want a v8 I'd build a chevy no offense here, I want the displacement and revs. Revs are key..
 
I don't think the 2 bolt mains require modifications, I believe that's a myth. So far not one main has blown out due to failure. What street driven VQ35's are making 1500+ HP easily? Good luck with your project.

Eric
 
I know of several bebop, as I worked with building them ;) Ls1s can make upwards of 2000hp why can't 1u? With enough boost you can do it easily, yes big CU big blocks have 2 bolt mains and can live just fine I agree, but, I just don't see what's wrong with the 1U + 3U or ported 1U Heads? That seems to be like the ticket. Why spend 20k on a motor, when you can spend 5 and hold 15-1800hp which it appears, the 1U can do very easily, now the quesiton is the head,s I know the 2u heads are more boost friendly, but I mean the 3U heads look to be the ticket, so my question is, 3u heads, 1u block, best of both worlds?

Or I could just drop in a SBC and turbo that and call it a day lol. But, I see no reason why the 1u can't make 1500-1800 hp, Because I've worked with 1400+ on the 3.0L with a big frame turbo, that block never had an issue, and the vq is one bad ass block with no problems even though aluminum I think it can be just fine, just as the 1U has plenty of mean and support for big boost and big power. I see no reason why it can't support a 101 and rev to 9500 and make an absurd about of power. I want simplicity, not a huge envolved build. That's what I'm saying. Why overcomplicate, sure a big ass 5.5 liter would be great, but a 1u with rods, pistons, rocked block, ported heads and big cams, that sounds simpler, and more practical.
 
Thanks man, no info on the 1uz bottom w/ a 3uz top? ;) or maybe even 2u heads, ? Curious on the differences between 98+ 1u heads vs the 3u heads.

Also the 3u blocks have to be sleeved again ? Im under that impression? Due to the piston incomapabilities?
 
It depends on the info that you're looking for, we're just starting to experiment with the 1/2uz. Is this for a strictly race motor that needs to survive one trip down the way, or for a motor that will need to be driven daily? Are the water passages going to be filled with quick-crete, or left intact? What price range are you looking at because if it's around the 5K mark that was mentioned before, the VVt-I heads will soak up about half of that cost.
 
Personally I feel the 1u will surrvive just fine down the track and driven around at a good level of power before failure. The VVTi I'd probably even leave out, I'd be looking for bare heads maximum power, it's of no use to me on the street, one less thing to worry about. So I'm strictly talking about head/block combonations. I'm going to try the 98+ 1U Bottom w/ either a set of those heads, or a set of 3U heads I don't care about the VVTi because I will eliminate it as is.
 
honestly i'd just use a stock stroke 1UZFE with some of the custom pistons, rods and cams on offer by approved vendors on this site. the cams will improve airflow and spool any exhaust driven power adder quicker and have you on boost earlier.

you said revs are the key - and you're right. a 1UZ will rev harder than a 2UZ and more reliably.

the 1UZ is also a lot cheaper.
 
yep exactly, that's what im going to try, question is, 1uz or 3uz heads? and im just going to find myself a 98+ block to work with for bottom, but wondering on the heads...are the 3u heads worth it? I've already sourced my internals out, wondering on the heads, fully built, VVTI blocked off etc. dont need it, lag doesn't bother me, besides it's not a problem 9 times out of 10, motec m800 controlled. SO

Question of the hour, 1uz or 3uz heads, worth it to go 3uz or stick with 1uz 98+ heads...? And btw, I presume they will bolt up, anyone here have any comments on wether they will or not. I like the 1uz meat between the block better than the 3uz much more room to work with not to mention the stock sleeves look fine. But, will the 3uz heads bolt up to a 98+ block? that's the question..
 
personally - the 1UZ is a pretty good bit of gear. i would use the stock heads with aftermarket cams and COPs and be done with it.

all the power is in the turbo / wastegate / manifolds selection.

i know it sounds awesome to have this and that on your engine, and that you used different heads and stuff, but at the end of the day is it REALLY going to be worth all that effort, time and money?

people run 8s with the stock heads and valves with different cams - i really don;t see how they can be that much of a problem. i mean, i'm sure there's something better out there (there always is) but is it worth it in the long run?
 
eh true, i think a 98+ 1uz looks to be perfect, rock the block , port the heads, that'sit forget about it.. ;)
 
add a turbo and all flow figures go out the window so i wouldn;t even bother porting the head.

i'm single turboing a pre 1994 1UZFE and apart from and aftermarket computer, cams and COPs i won't be touching the engine at all.

my power goal is a minimum 450hp at the wheels at 1bar of boost. i'm confident it's achieveable on a stock motor with cool boost and good fuel.
 
If you going to do combination setup like 1u with 3u heads. Then u really need two different engines to make this work or at least a complete 1uz short block and a complete 3u upper. 3u upper means lower intake and upper intake and all other electronics and sensors. Please someone correct me if i am wrong. Pre and post 98 have different head configuration as far as the head/intake.

The best choice would be 98+ 1uzfe. However, the newer motors are very expensive.

1u is about $600
98+ 1uzfe is about 3000
3uzfe is about 4k
2uzfe is about 1500-2000

As for me I am using a 2uzfe iron block with 4 bolt conversion with H beam rod with custom forged pistons.
 
thanks for the info! I think the 1U looks to be the best bet, a 98+ 1U

basically everything on the block is the same on the 1u vs the 3u?

also anyone have any pictures of the bottom end of the 1u vs. the 3u, maybe lextreme can comment? ;) I want to see the oiling system see if it is indeed as good as people say.
 
1 UZ VVTI AND 3 UZ VVTI Share the same heads the 2 uz are almost the same but dont have vvti these heads flow alot better std than non vvti
supercharger manifold and or full kit available for these shortly with or without water too air intercooler to suit ls 400 / 430 landcruiser / lx470
all of the above heads are different to the non vvti 1uz heads
hope this helps
 


Back
Top