The thick 1uz rods are indeed weak
#16
Driver School Candidate
I am not judging or doubting Arnout's experience and ability, but twisting bare metal on a vice doesn't impress me.
1uz rod is more brittle than the others, that's the fact, but weak? that's more a relative term than an absolute statement.
I mean com'on, throw some hard number out instead of just plain saying 1uz rod is weak. You mentioned that failed 1uz engine has shatter ring land, it is obvious that the piston design of application was not intend of high boost(shallow ring land), and it doesn't have much tolerance to detonation; Another sign of abrupt cylinder pressure due to tuning error/limit, therefore it has nothing to do with a "weak" rod.
It is misleading to say 1uz rod is weaker than 2jz rod base on torsional strength. You will NOT see that much of torsional load apply to the rod, they are design for compression and tension, so their fatigue strength is what's important, NOT torsional. 1uz failed under torsional "test" proof nothing, because connecting rod are not design to do such job.
ps. you might have to pay attention to the grain flow of the metal too, who knows how the 1uz rod was being manufacture? How many 1uz rods you guys put through in this type of "destructive testing"? What is the trend line of the result? I've seen 2jz throw a rod with just 500rwhp before, does it mean they are weak? I don't think so. I need to see some repeatable data to convince me to accept this "fact"
1uz rod is more brittle than the others, that's the fact, but weak? that's more a relative term than an absolute statement.
I mean com'on, throw some hard number out instead of just plain saying 1uz rod is weak. You mentioned that failed 1uz engine has shatter ring land, it is obvious that the piston design of application was not intend of high boost(shallow ring land), and it doesn't have much tolerance to detonation; Another sign of abrupt cylinder pressure due to tuning error/limit, therefore it has nothing to do with a "weak" rod.
It is misleading to say 1uz rod is weaker than 2jz rod base on torsional strength. You will NOT see that much of torsional load apply to the rod, they are design for compression and tension, so their fatigue strength is what's important, NOT torsional. 1uz failed under torsional "test" proof nothing, because connecting rod are not design to do such job.
ps. you might have to pay attention to the grain flow of the metal too, who knows how the 1uz rod was being manufacture? How many 1uz rods you guys put through in this type of "destructive testing"? What is the trend line of the result? I've seen 2jz throw a rod with just 500rwhp before, does it mean they are weak? I don't think so. I need to see some repeatable data to convince me to accept this "fact"
#17
Banned
Thread Starter
I am not judging or doubting Arnout's experience and ability, but twisting bare metal on a vice doesn't impress me.
1uz rod is more brittle than the others, that's the fact, but weak? that's more a relative term than an absolute statement.
I mean com'on, throw some hard number out instead of just plain saying 1uz rod is weak. You mentioned that failed 1uz engine has shatter ring land, it is obvious that the piston design of application was not intend of high boost(shallow ring land), and it doesn't have much tolerance to detonation; Another sign of abrupt cylinder pressure due to tuning error/limit, therefore it has nothing to do with a "weak" rod.
It is misleading to say 1uz rod is weaker than 2jz rod base on torsional strength. You will NOT see that much of torsional load apply to the rod, they are design for compression and tension, so their fatigue strength is what's important, NOT torsional. 1uz failed under torsional "test" proof nothing, because connecting rod are not design to do such job.
ps. you might have to pay attention to the grain flow of the metal too, who knows how the 1uz rod was being manufacture? How many 1uz rods you guys put through in this type of "destructive testing"? What is the trend line of the result? I've seen 2jz throw a rod with just 500rwhp before, does it mean they are weak? I don't think so. I need to see some repeatable data to convince me to accept this "fact"
1uz rod is more brittle than the others, that's the fact, but weak? that's more a relative term than an absolute statement.
I mean com'on, throw some hard number out instead of just plain saying 1uz rod is weak. You mentioned that failed 1uz engine has shatter ring land, it is obvious that the piston design of application was not intend of high boost(shallow ring land), and it doesn't have much tolerance to detonation; Another sign of abrupt cylinder pressure due to tuning error/limit, therefore it has nothing to do with a "weak" rod.
It is misleading to say 1uz rod is weaker than 2jz rod base on torsional strength. You will NOT see that much of torsional load apply to the rod, they are design for compression and tension, so their fatigue strength is what's important, NOT torsional. 1uz failed under torsional "test" proof nothing, because connecting rod are not design to do such job.
ps. you might have to pay attention to the grain flow of the metal too, who knows how the 1uz rod was being manufacture? How many 1uz rods you guys put through in this type of "destructive testing"? What is the trend line of the result? I've seen 2jz throw a rod with just 500rwhp before, does it mean they are weak? I don't think so. I need to see some repeatable data to convince me to accept this "fact"
This thead was simply for GP, but if you'd like to embark on destructive testing, then I'll help if I can. I beleive you'll confirm the same results however.
Thanks again!
Eric
#19
BahHumBug
iTrader: (10)
Who? Who threw a 2jz rod at 500HP? Was is directly attributed to the rod itself? Stock twins approach that figure. All I'm saying is that todays tuner standards, the 1uz rod doesn't seem up to snuff. The rod failures documented seem to support that. 500-600rwhp sounds like a lot, but by todays tuner standards, it's really not. Respectable but hardly the upper limt. There is no hard number as you say, but you can figure at somewhere between ~550rwhp it's on the ragged edge.
This thead was simply for GP, but if you'd like to embark on destructive testing, then I'll help if I can. I beleive you'll confirm the same results however.
Thanks again!
Eric
This thead was simply for GP, but if you'd like to embark on destructive testing, then I'll help if I can. I beleive you'll confirm the same results however.
Thanks again!
Eric
#21
Driver School Candidate
Who? Who threw a 2jz rod at 500HP? Was is directly attributed to the rod itself? Stock twins approach that figure. All I'm saying is that todays tuner standards, the 1uz rod doesn't seem up to snuff. The rod failures documented seem to support that. 500-600rwhp sounds like a lot, but by todays tuner standards, it's really not. Respectable but hardly the upper limt. There is no hard number as you say, but you can figure at somewhere between ~550rwhp it's on the ragged edge.
This thead was simply for GP, but if you'd like to embark on destructive testing, then I'll help if I can. I beleive you'll confirm the same results however.
Thanks again!
Eric
This thead was simply for GP, but if you'd like to embark on destructive testing, then I'll help if I can. I beleive you'll confirm the same results however.
Thanks again!
Eric
j/k I see what you are trying to say.
I think you have missed my point. What I said earlier is, doing this "test" with torsional load is a misleading way to judge and say 1uz rod is WEAK (a relative term). And I mentioned, by doing it only ONCE doesn't mean anything at all, the result means nothing.
I made an example about a 500rwp 2jz threw a rod, chit happened, and our only guess is a defected rod. But does it mean all 2jz rod are bad? NO.
So there are a few 500rwhp 1uz failed due to rod failure, you can't really tell everyone all 1uz rod are weak and not "up to snuff"
no doubt, 2jz internal is stout and has been proven by many many successful case, no argue about it. I just want to stand up for the 1uz rod a little bit because I don't think the torsional "test" is a fair test.
Its been fun guys
#22
Driver School Candidate
how about this... since i have time this weekend.
Can anyone of you give me or direct me to find the exact dimension and geometry of the 2jz, 3S, and 1uz rod?
I can do FEA(Finite element analysis) on it and the model can tell us which rod is "the best" by making an assumption with - they all have the same modulus of elasticity, Poisson's ratio, and same amount of load applied to it.
But then again, that will only prove which design/geometry is the best, it has nothing to do with the alloy formula and the dynamic loading (Fatigue) from the real world.
It still fun to find out. BTW, I use ProE and ANSYS
Can anyone of you give me or direct me to find the exact dimension and geometry of the 2jz, 3S, and 1uz rod?
I can do FEA(Finite element analysis) on it and the model can tell us which rod is "the best" by making an assumption with - they all have the same modulus of elasticity, Poisson's ratio, and same amount of load applied to it.
But then again, that will only prove which design/geometry is the best, it has nothing to do with the alloy formula and the dynamic loading (Fatigue) from the real world.
It still fun to find out. BTW, I use ProE and ANSYS
#23
Banned
Thread Starter
Good debate man. I very much think the crucible is in the motor, and it's been shown that they crap out early. What's meant by tuner standard is what's come to be the norm for the 2jz since the 2jz seems to be the top of the mountain in the tests.
Also if you like, I'm sure we could arrange for a dozen of so 1uz rods to be tested, however again I very much feel the result will be the same. I also realize that this is CL and the 1uz has a small but devoted following. My point in the post is to bring to light the fact that when FI is applied to the motor, after a certain point, it's a bomb waiting to go off. I've heard folks say that the stock rods top out at ~600-650rwhp, and if the motor survives that blast then fine, it just won't for long.
The way I see it, we can send all the rods out for testing and they might come back in a few months [if that] and give us a load of random numbers that frankly don't mean jack in the real world. They also might ask for a load of cash which someone will need to front. Or........ we can affix the rods in a vice and find out exactly what they're made of, and have the test done by a very qualified engine builder / tuner right there on the spot.
If you like I can ask Arnout to affix new rods back into the vice and use a giant breaker bar to bend them over. Wanna take bets as to those results?
Edit in repsonse to the post above: The FEA would indeed give a result but it would be based on the geometry of the rod [as you said], and not the construction. I know the 1uz rod is made from sintered iron, but I'm not sure what the 2jz exactly is made from or how it's constructed. It's tough as a coffin nail though so my assumption would be that it's made in a different way than the 1uz.
Thanks!
Eric
Also if you like, I'm sure we could arrange for a dozen of so 1uz rods to be tested, however again I very much feel the result will be the same. I also realize that this is CL and the 1uz has a small but devoted following. My point in the post is to bring to light the fact that when FI is applied to the motor, after a certain point, it's a bomb waiting to go off. I've heard folks say that the stock rods top out at ~600-650rwhp, and if the motor survives that blast then fine, it just won't for long.
The way I see it, we can send all the rods out for testing and they might come back in a few months [if that] and give us a load of random numbers that frankly don't mean jack in the real world. They also might ask for a load of cash which someone will need to front. Or........ we can affix the rods in a vice and find out exactly what they're made of, and have the test done by a very qualified engine builder / tuner right there on the spot.
If you like I can ask Arnout to affix new rods back into the vice and use a giant breaker bar to bend them over. Wanna take bets as to those results?
Edit in repsonse to the post above: The FEA would indeed give a result but it would be based on the geometry of the rod [as you said], and not the construction. I know the 1uz rod is made from sintered iron, but I'm not sure what the 2jz exactly is made from or how it's constructed. It's tough as a coffin nail though so my assumption would be that it's made in a different way than the 1uz.
Thanks!
Eric
Last edited by c0wboy; 02-01-08 at 01:04 PM.
#24
Lexus Champion
iTrader: (-1)
I am also not surprised that the 7M, 3S, and 2JZ rods held up like they did. There is no doubt that those motors were more purpose built for performance than the 1UZ, which was for all intents meant to be solely a passenger car engine.
I know most of the guys going FI on the 1UZ have the integrity of the bottom end at the forefront of their mind when making their build. I know I do. Anything more than 400whp, and you start playing with fire.
That being said, there is a Twin Turbo 1UZ Celica owner from Australia on Lextreme who is pushing 400+rwkw on a stock 1UZ bottom end. I think good tuning and the health of the motor can make all the difference in the world when you exceed 400whp and do start playing with fire.
#25
Lexus Champion
iTrader: (4)
Wow, this is a wonderful diatribe going back and forth on this one...I especially love all the color adjectives being thrown back and forth, right on Eric...I see your points, all of you. I certainly understand being "scientific", and also being in the "real world". Each has its merit. But I also have to agree that to state that the 1UZ rods are weak from these tests is not highly accurate. Nothing against you, Eric, or Arnout...
Bringing up Chris Mantes and the TT 1UZ he bent that rod from, if you remember, Chris did imply there was a tuning issue, and I did personally discuss this with him, the cylinder ran lean, not a condition that is conduscive to the longevity to any rod, ring land, or piston...Especially in a boosted application.
I also agree that if anyone plans to boost their 1UZ, they should seriously consider swapping in forged internals, and a completre engine rebuild if they are interested in longevity. But, that needs to be coupled with proper tuning. Improper tuning, and the best parts will not hold up.
Remember this as well, the 1UZ was never intended for boost in its design from Toyota. So, why would anyone who is serious about boosting one not add forged internals?
Ryan
Bringing up Chris Mantes and the TT 1UZ he bent that rod from, if you remember, Chris did imply there was a tuning issue, and I did personally discuss this with him, the cylinder ran lean, not a condition that is conduscive to the longevity to any rod, ring land, or piston...Especially in a boosted application.
I also agree that if anyone plans to boost their 1UZ, they should seriously consider swapping in forged internals, and a completre engine rebuild if they are interested in longevity. But, that needs to be coupled with proper tuning. Improper tuning, and the best parts will not hold up.
Remember this as well, the 1UZ was never intended for boost in its design from Toyota. So, why would anyone who is serious about boosting one not add forged internals?
Ryan
#26
Banned
Thread Starter
Wow, this is a wonderful diatribe going back and forth on this one...I especially love all the color adjectives being thrown back and forth, right on Eric...I see your points, all of you. I certainly understand being "scientific", and also being in the "real world". Each has its merit. But I also have to agree that to state that the 1UZ rods are weak from these tests is not highly accurate. Nothing against you, Eric, or Arnout...
Bringing up Chris Mantes and the TT 1UZ he bent that rod from, if you remember, Chris did imply there was a tuning issue, and I did personally discuss this with him, the cylinder ran lean, not a condition that is conduscive to the longevity to any rod, ring land, or piston...Especially in a boosted application.
I also agree that if anyone plans to boost their 1UZ, they should seriously consider swapping in forged internals, and a completre engine rebuild if they are interested in longevity. But, that needs to be coupled with proper tuning. Improper tuning, and the best parts will not hold up.
Remember this as well, the 1UZ was never intended for boost in its design from Toyota. So, why would anyone who is serious about boosting one not add forged internals?
Ryan
Bringing up Chris Mantes and the TT 1UZ he bent that rod from, if you remember, Chris did imply there was a tuning issue, and I did personally discuss this with him, the cylinder ran lean, not a condition that is conduscive to the longevity to any rod, ring land, or piston...Especially in a boosted application.
I also agree that if anyone plans to boost their 1UZ, they should seriously consider swapping in forged internals, and a completre engine rebuild if they are interested in longevity. But, that needs to be coupled with proper tuning. Improper tuning, and the best parts will not hold up.
Remember this as well, the 1UZ was never intended for boost in its design from Toyota. So, why would anyone who is serious about boosting one not add forged internals?
Ryan
Eric
#29
Not only was this not scientific, but the fact that you are selling turbo kits and are a direct contact for someone building up 1UZs for customers removes all legitimacy from your post.
No offense, Eric, but this post is as clear as glass.
No offense, Eric, but this post is as clear as glass.
#30
Banned
Thread Starter
http://www.v-eight.com/tech_forum/vi....php?f=5&t=599
I hope this sheds some light. Next time find out the truth before throwing stones, please.
Eric