Questions about the 1uz rods?

[The Flea]

I just took down my 92 1UZ and was blown away by how incredibly weak the rods appeared. I know appearances aren't everything. The manual says the rods are forged, which to my understanding is common among most high end Japanese engines. I compared them to a N/A VQ30 rod and it made the 1UZ look like something out of a lawnmower. The TT VQ30 was even more impressive. In comparison, the rods looked closer to a single cam Honda than the beefy Nissan parts.

So.. I read about how much some of you guys are throwing at them with no problems. Am I to believe what I read without a doubt? I don't think that I've read about any rod failures among us?? Knock on wood.

I've only seen a few dyno runs actually documented, everything else has been heresay. What gives?

 

[Pro]

there's a 9sec celica here in west oz that run 20psi boost on an internally std engine with no decompression.

he only blew the engine trying to stuff in 25psi - until then it had over 20 full noise passes under it's belt and made over 600kw on methanol.

considering that all he did was replace the bearings, the 2 cracked pistons, re-ringed it and put it back together after a light hone i think is testament to the engine's bottom end strength, rods and all.

he's still running this engine while he builds a decompressed engine for more boost and more methanol using only custom pistons for the moment.

last i heard it ran a flat 9 in a "street reg" car - but that was with the old 20psi setup and a powerglide.

 

[quadcam boat]

I am told that the rods are good for 600hp but won't make 650hp. Thats from a guy drag racing a supercharged one.

 

[R-Jay]

didnt know there was such an engine from the factory... VQ30 TT that is. From what i know about nissans (i use to be a nissan loving guy)... the only forced induction VQ30's came in the Y33 chassis such as the leopards and other JDM only cars.

maybe you mean the VG30dett from the 300zx... then again, i could be wrong, hehe

i too am interested to know about the rods... so they are forged??? i was under the impression that only the crank was forged....

 

[Pro]

i'm pretty sure the rods are forged too.

 

[Dreamkiller]

From the zoom magazine that celica was making 522hp @ wheels and ran a 9.2.

 

[Lextreme II]

Thanks to www.tmengineering.net. Todd donated a custom set of Forged Cumming Rods to our site. They can handle about 900 rwhp as stated by TME. I will try to find some pictures.

Those forged rods will accompany by the upcoming forged pistons from Larry Edynn along with MLS and ARP studs....... You know what it means? SICK!!!!

 

[R-Jay]

holy crap... aftermarket parts? FINALLY!!!!!!!

so are these businesses actually going to start manufacturing rods, pistons, gaskets, and studds for aftermarket mods????

 

[Lextreme II]

Rods = Custom
Pistons = Custom (you still can jump in for a set)
Gaskets = Available now
Studs = Available now

 

[R-Jay]

so what are the prices on the studs and MLS???

 

[Lextreme II]

Here are the Cumming Rods http://www.lextreme.com/forums/showthread.php?t=1529

 

[Pro]

i was looking at the rods in tech section and they don't look weak at all...

they might be thin, but the areas around the main bearing have a nice exponential transition into the rod, and the rod has a nice exponential transition into the wrist pin area.

it's not all about meat.

 

[Dreamkiller]

Only thing left now are cams!

 

[Zuffen]

Kelfords in NZ are working on them. They hope for more news in November

I stay in tough with Tony to see how they are going.

 

[The Flea]

Here are a few pics of the differences in the >VG30< (oops R-jay) non-turbo rod vs. the 1UZ-FE rod.
The first thing is the size. The Nissan rod is considerably bigger, but quite a bit heavier. With the Nissan rod, the scalloping in the beam isn't as deep or narrow. The taper on the beam isn't as drastic either. The big end has more meat and the rod bolts have nuts.
The side profile scares me the most. The forging marks are easily identifiable on the Nissan rod, where our rod looks cast--having no punch marks. I've read where the manual states the rods are forged. Have they ever used "forged" to mean "pressed metal" like the pressed powdered rods?

I know some of you might say, "size isn't everything". Maybe so. Lighter reciprocating parts place less load on the rod and the bolts (where most failures begin). The 1UZ piston is incredibly light compared to the VG30. As the assembly is brought down from TDC during the overlap, the tensile load placed on the rod is at it's greatest. But if the sled (piston) is light, then the ropes needed to pull the sled can be less too.

The last picture is from a mild 428 Pontiac with 650bhp. The Brooks 7075 T6 aluminum rod looks like it just broke in the middle. The failure actually started with a rod bolt. In this case it was improperly torqued.

 

[cars noddy]

getting back to the subject of how small the rods are, you have to remember how many cubes are sitting on top of each one. this is a high reving small displacment engine, just like 2 4cyl engine of which is what you should be comparing these rods to. based on what i have uncovered through reading, its not an area that you need not worry about. just get one rev it and fined out for your self they are a freak engine in disguise.

after i put on in my boat, i am going to look at a drag car.
Paul

 

[Zuffen]

Whilst my dog may disagree "nuts aren't everything"! Toyota didn't put long bolts plus nits as they clearly were not needed.

Cars Noddy hit the nail on the head.

These engines are so cheap give them a rev and wait for the bang. You may surprised how long it takes to kill one of these.

I would not upgrade rods unless I thought I would see more than 700HP. Lots of people say 650 is the limit but how many of us have a transmission that can handle 650+ HP on the street?

 

[R-Jay]

i do, hehe.... well, it isnt in use yet... but soon will be... Getrag v160 if you're curious.

 

[Zuffen]

R-Jay,

You had better bring that thing along to the Sydney Meet in December.

Very interested in anything that can handle that sort of grunt.

 

[Red Supra]

I found out a few days ago from a Toyota powertrain division employee that a stock 1uz will handle 1000hp with ease with a proper tune.

I send out a stock 1uz connecting rod to ARP yesterday for some better rod bolts, once they do come up with a part number i'll be sure to post it here.
I found one aftermarket company that makes bearings for the 1uz. King Bearings is the name and i've heard good thing of them. I'm hoping that Cleavite will be able to put a bearing kit for street and race applications.