1GZ Rod Strength

bahaimus

New Member
Not much as it turns out.



This is a cross sectional piece of the rod that came out the side of my block during dyno tuning yesterday. Boosted engine, 12psi, only making about 345rwhp at the time.

For players outside of Australia, that 5 cent piece is 20mm in diameter.
 

cribbj

"Supra" Moderator
Staff member
Eyouch!!! Sorry for your troubles, but thanks for the heads up. Very good for the community to know that this motor has such a weak bottom end.

Any pics of your setup?
 
hmmmmm 1gz rods are very similar to late 1uz rods i'm putting out 288rwhp through 8 rods! what are you spinning the thing too and to you have the ecu logs from the dyno?
 

bahaimus

New Member
My setup looks like this:



Stock (unknown history) engine with a GT4088R and a T56 gearbox.

This failure happened while the boost controller was being setup at 345rwhp and 4500rpm. Everything was safe - rich mixtures, minimal timing, no cam advance and E85 fuel.
 

JustenGT8

New Member
That should be well past peak torque too, but it's not a high rpm rod failure.

Weird as based on what the UZ skinny rod can take, these things should be good for 500ish rwhp?

Tear down and see if there was any obvious cause i guess. Blows that it holed the block :(

Built engine or new stock one running 8psi max?
 

bahaimus

New Member
That should be well past peak torque too, but it's not a high rpm rod failure.

Weird as based on what the UZ skinny rod can take, these things should be good for 500ish rwhp?

Tear down and see if there was any obvious cause i guess. Blows that it holed the block :(

Built engine or new stock one running 8psi max?
Yeah, as you said, we figured 500rwhp on E85 over 12 rods should have been "safe".

Tear down will happen. Could have been a rod bolt failure too. Time will tell.

No money for a forged build at this time. Likely outcome is another stock engine in NA form with some basic headers for aural pleasure and still a reasonably quick 190E.
 

JustenGT8

New Member
n/a would still go good based on how Norbies Century goes once up and moving...and that pig is well over 2 tonne :)
 

redrocco

Member
I was wondering if I could buy a pair of the rods and pistons from your dead engine and maby the crank? I have been researching the posablity of useing the rods and pistons from the Honda B16A1 engine in my 1GZ-FE. I would post up everything I figure out on lextreme so every one would benefit. I would be able to use a pair of your rods to get proper dimentions useing the CMM machine where I work and might be able to figure out how to use master cam to make a drawing of them. Plus I could conduct the B16 rod swap with out having to take my 1GZ apart. The B16A1 rod piston swap would require the crank to be ground and to have a crank in hand to study that would be very helpful.

Thanks
 

bahaimus

New Member
Sorry, I'd forgotten I'd posted this thread. Y'all deserve an update!

Some more pics of the destruction.

Offending rod. Other half and piston are firmly jammed into the bore.



Rod journal is perfect.



Block is not perfect.



I was able to source another engine quite quickly. The decision was taken to move forward NA with a nice set of headers.

Here's the headers in kit form LOL! :D



There's been a few hiccups with this engine, but finally some results!

So, this:



+ this:



+ this:



= this!

Putting it away for the night - YouTube

Trying to capture the sound - YouTube

I was wondering if I could buy a pair of the rods and pistons from your dead engine and maby the crank? I have been researching the posablity of useing the rods and pistons from the Honda B16A1 engine in my 1GZ-FE. I would post up everything I figure out on lextreme so every one would benefit. I would be able to use a pair of your rods to get proper dimentions useing the CMM machine where I work and might be able to figure out how to use master cam to make a drawing of them. Plus I could conduct the B16 rod swap with out having to take my 1GZ apart. The B16A1 rod piston swap would require the crank to be ground and to have a crank in hand to study that would be very helpful.

Thanks
Hey there, I haven't got the engine at home yet, but when I do, I'm happy to send a couple of intact rods and pistons to you if you'd just be happy to cover the shipping (I'm in Australia).

I'm planning to hang on to the crank for a future potential build though.

So what will you do with the block?
Can you source a new motor?
Is it repairable?
This is a big surprise...:confused::mad:
I'm going to get the block home and show it to a local engineering company to see if they can weld it up. If they can, it is planned to form the basis of a future more i performance NA build. If they can't, a UK Top Gear style V12 coffee table.
 

hungryforinfo

New Member
Would love to hear how they go with welding it up.
P.s. I can give you pointers on how to get the best out of your coffee table, have made a few 1UZ ones.

Also, where did you source the engine from and roughly how much??
Was it Qld??
 

redrocco

Member
A pair of rods and pistons would be ausome, thank you in advance. When your ready to ship them let me know the cost and how you would like me to send the money to you. I will PM you my full address. I am also planning on getting my 1GZ running NA to start off and work the bugs out. Have you found any reason for the rod failure other then them being week/under sized? I would love to go twin turbo with this engine but with how hard it is to get parts I don't want to take any more risks then nessasary.
 

bahaimus

New Member
Would love to hear how they go with welding it up.
P.s. I can give you pointers on how to get the best out of your coffee table, have made a few 1UZ ones.

Also, where did you source the engine from and roughly how much??
Was it Qld??
Apparently they've done quite a few race motors in the past, so they are well versed in the process.

Another guy in Kingaroy had one for his project that he is not using yet. We did a deal. The going rate seems to be about $3500. I know where there is one that might be available in QLD if you want one.

A pair of rods and pistons would be ausome, thank you in advance. When your ready to ship them let me know the cost and how you would like me to send the money to you. I will PM you my full address. I am also planning on getting my 1GZ running NA to start off and work the bugs out. Have you found any reason for the rod failure other then them being week/under sized? I would love to go twin turbo with this engine but with how hard it is to get parts I don't want to take any more risks then nessasary.
No problem.

As I said above, I think it was a combination of too weak, plus the amount of torque it was making low in the rev range. The guy who built this for me also built another turbo 1GZ car, but it was auto with a big stall, so it couldn't make the down low torque mine was making and hasn't broken. With decent rods and pistons, it should be fine.

I saw your thread asking about custom cams as well. This is relevant to my interests as well. I'll give Kelford Cams in New Zealand a call next week if you like. Let me know if there are any specific questions you want to know the answer to. There's a couple of other cam grinding places here in Australia too.
 
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