Are stock rods suitable for FI VQ engines?
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From: Nuclear Power
Originally posted by nis350ztt
Ok...the real question is what do the bearings look like with the stock turbo/supercharger system after quite a bit of miles?
IF they look like they are far too worn for only a certain amount of power, then the solution may be to get:
Larger oil pan and better (pumps more at a faster rate and has a larger capacity) oil pump.
or
enlargen the oil holes (not feasible)
or
switch to a dry-sump system (not feasible for the price).
So what we have weighing against us is:
Weak rods
Unshielded crankshaft and camshaft angle sensor wire may produce scattered ignition timing
Potential oil starvation problem which can be solved for the cheapest amount is a larger oil pan and larger capacity, quicker flow rate at a larger pace.
Stock fuel system is inadequate over 400rwhp.
Ok...the real question is what do the bearings look like with the stock turbo/supercharger system after quite a bit of miles?
IF they look like they are far too worn for only a certain amount of power, then the solution may be to get:
Larger oil pan and better (pumps more at a faster rate and has a larger capacity) oil pump.
or
enlargen the oil holes (not feasible)
or
switch to a dry-sump system (not feasible for the price).
So what we have weighing against us is:
Weak rods
Unshielded crankshaft and camshaft angle sensor wire may produce scattered ignition timing
Potential oil starvation problem which can be solved for the cheapest amount is a larger oil pan and larger capacity, quicker flow rate at a larger pace.
Stock fuel system is inadequate over 400rwhp.
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From: Atlanta
There is the option of adding a secondary electric oil boost pump (with regulator).
(This product isn't really for individual consumers, but should relate the idea)
http://www.dana.com/technology/intelligentLub.shtm
An added bonus is that you get oil pressure before you crank your car. And the secondary oil pickup could be placed in such a way that it's likely to pump oil when the other pickup is starving. Also, oil pressure is much more constant and less dependent on RPM. You could even put in a less powerful mechanical oil pump (if available) and you'd have less parasitic HP loss.
That said, if the simple approach of a better oil pan for baffles and cooling solves any oil-related issues, then there is no point in doing the electric oil boost pump.
--
Jeff
(This product isn't really for individual consumers, but should relate the idea)
http://www.dana.com/technology/intelligentLub.shtm
An added bonus is that you get oil pressure before you crank your car. And the secondary oil pickup could be placed in such a way that it's likely to pump oil when the other pickup is starving. Also, oil pressure is much more constant and less dependent on RPM. You could even put in a less powerful mechanical oil pump (if available) and you'd have less parasitic HP loss.
That said, if the simple approach of a better oil pan for baffles and cooling solves any oil-related issues, then there is no point in doing the electric oil boost pump.
--
Jeff
I saw this one and was wondering if it would work.
http://www.emp-corp.com/html/product...c_oil_pump.htm
http://www.emp-corp.com/html/product...c_oil_pump.htm
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From: Houston
Originally posted by 2JZfan
You guys really should calm down a bit. This whole platform is so new that everybody is just DYING to jump on some kind of bandwagon. "What? This is the magic solution? Just buy part X and everything will be ok?!" It's hardly ever that simple... But at the same time, I don't take any offense to Peter's comments and I think it's insulting to him to say his intent was to play anyone like a puppet. He opened a discussion asking for other people's input and feedback and he simply stated his theory. He did not make any sort of crazy marketing claim. If in fact no APS customers have lost a motor, then the only "sales pitch" he threw out there was actually just a statement of fact. I am happy to see anyone that is willing to share information that was gained after many hours of testing and dollars spent. MANY companies would be much more inclined to say "don't worry about why it is, just buy our kit, we have secret mojo built in, etc.". Hell, you could argue that Peter is risking LOSING sales with his statements because now people could do a cheaper Greddy kit and just add the APS pan, if in fact that is a solution to this problem.
A few comments/questions come to my mind:
Has anyone lost a motor on the dyno? In this environment you take g-forces out of the equation and even a stock pan should be able to keep up with the oil consumption. If motors have blown in this environment, it somewhat rules out being a purely baffling related problem. Heat issues may still exist, but doing a few pulls on the dyno should not cause any kind of fatal breakdown on a decent oil.
In my experience, spun bearings are often caused by the rod distorting under load (usually high rpm), this "pinches" the bearing enough that it cuts through the oil layer and makes contact with the spinning crank. When the two surfaces contact, the bearing "spins" in the rod. Bearing wear will be rapid after this. The increased clearance caused by bearing material being scraped away causes "rod knock" and shortly thereafter you can expect the rod bolts to break. Of course, losing oil pressure would have this same result of allowing metal on metal contact, but as someone else pointed out: if it's just based on oil pressure and pan baffling, and not the extra strains from the increased HP, there should be more NA road racers losing motors than FI street guys.
It hardly seems that enough evidence has been presented on either side of this issue a) to buy into 100% or b) to ignore it.
And for those that think it's just "insane" to think you can make 400+rwhp reliably on a stock motor, just remember there was a time when the 2JZ was thought to max out around that power level. Did somebody from Toyota sneak back into all of our garages and add forged internals? Nope, in fact, our motors are even older and in theory weaker now than they were back then. And yet 600-800rwhp on STOCK motors is so commonplace now that you don't even get credit for hitting these marks. So don't rule out the VQ in stock form just yet. (Of course my money is on the '05 motors being even stronger, especially in the rod department
)
It all remains to be seen!!
You guys really should calm down a bit. This whole platform is so new that everybody is just DYING to jump on some kind of bandwagon. "What? This is the magic solution? Just buy part X and everything will be ok?!" It's hardly ever that simple... But at the same time, I don't take any offense to Peter's comments and I think it's insulting to him to say his intent was to play anyone like a puppet. He opened a discussion asking for other people's input and feedback and he simply stated his theory. He did not make any sort of crazy marketing claim. If in fact no APS customers have lost a motor, then the only "sales pitch" he threw out there was actually just a statement of fact. I am happy to see anyone that is willing to share information that was gained after many hours of testing and dollars spent. MANY companies would be much more inclined to say "don't worry about why it is, just buy our kit, we have secret mojo built in, etc.". Hell, you could argue that Peter is risking LOSING sales with his statements because now people could do a cheaper Greddy kit and just add the APS pan, if in fact that is a solution to this problem.
A few comments/questions come to my mind:
Has anyone lost a motor on the dyno? In this environment you take g-forces out of the equation and even a stock pan should be able to keep up with the oil consumption. If motors have blown in this environment, it somewhat rules out being a purely baffling related problem. Heat issues may still exist, but doing a few pulls on the dyno should not cause any kind of fatal breakdown on a decent oil.
In my experience, spun bearings are often caused by the rod distorting under load (usually high rpm), this "pinches" the bearing enough that it cuts through the oil layer and makes contact with the spinning crank. When the two surfaces contact, the bearing "spins" in the rod. Bearing wear will be rapid after this. The increased clearance caused by bearing material being scraped away causes "rod knock" and shortly thereafter you can expect the rod bolts to break. Of course, losing oil pressure would have this same result of allowing metal on metal contact, but as someone else pointed out: if it's just based on oil pressure and pan baffling, and not the extra strains from the increased HP, there should be more NA road racers losing motors than FI street guys.
It hardly seems that enough evidence has been presented on either side of this issue a) to buy into 100% or b) to ignore it.
And for those that think it's just "insane" to think you can make 400+rwhp reliably on a stock motor, just remember there was a time when the 2JZ was thought to max out around that power level. Did somebody from Toyota sneak back into all of our garages and add forged internals? Nope, in fact, our motors are even older and in theory weaker now than they were back then. And yet 600-800rwhp on STOCK motors is so commonplace now that you don't even get credit for hitting these marks. So don't rule out the VQ in stock form just yet. (Of course my money is on the '05 motors being even stronger, especially in the rod department
)It all remains to be seen!!
Very well put. I just want to reiterate your point of "Just buy part X and everything will be ok?!" It's hardly ever that simple... " I think car magazines and movies somewhat depict modding as slapping on a turbo kit and you will make X amount of power and everything will be just copacetic. What in fact we're doing is reengineering a car. Not easy w/o schooling, the tools, the parts, or years of expierence. The FI VQ35DE community will have to mature like any other and the cost will be paid in motors.
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From: Australia
Originally posted by nis350ztt
His car is the perfect example. He has the APS oil pan, and the kit has the shielded wires, and apparently he can tune fairly well. So if his motor lasts a long time under extreme stress, this will start to show us what is really wrong with the VQ35DE.
His car is the perfect example. He has the APS oil pan, and the kit has the shielded wires, and apparently he can tune fairly well.
So if his motor lasts a long time under extreme stress, this will start to show us what is really wrong with the VQ35DE.
Let's not confuse these two seperate issues here, one issue is con rod failure caused via a big end bearing failure/lack of oil supply via oil starvation, (no con rod will survive big end bearing failure) the other issue is the con rods absolute mechanical strength.
Peter
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From: Australia
Originally posted by barthelb
440rwhp with stock internals on an APS TT kit should be pretty safe. (Plus if oil temp is part of the issue, you have the cooler for added protection) Yes, worse case i have cool running oil which makes since anyway. For a layman like myself I figured a hot running engine lets address that. Cooler oil and better radiator!
440rwhp with stock internals on an APS TT kit should be pretty safe. (Plus if oil temp is part of the issue, you have the cooler for added protection) Yes, worse case i have cool running oil which makes since anyway. For a layman like myself I figured a hot running engine lets address that. Cooler oil and better radiator!
Peter
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From: Australia
Originally posted by 350zDCalb
my advise, don't push it...stay below 400rwhp...take the additional precautions (upgrade fuel system even further)..and plan on a rebuild w/in a year at the most!
boohoo
my advise, don't push it...stay below 400rwhp...take the additional precautions (upgrade fuel system even further)..and plan on a rebuild w/in a year at the most!
boohoo
To date everyone has assumed that the stock con rod is mechanically weak and can't support high power safely (I don't think this is absolutely true), in addition I'm sure that even a high quality con rod won't survive if oil starvation hence big end bearing failure is a reality under certain road/engine conditions.
Peter
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From: Atlanta
Different types of bearing damage:
http://www.dana.com/Automotive_Syste...age%20rev.aspx
With enough examples, it looks like bearing damage could be evaluated in a fairly straightforward manner.
--
Jeff
http://www.dana.com/Automotive_Syste...age%20rev.aspx
With enough examples, it looks like bearing damage could be evaluated in a fairly straightforward manner.
--
Jeff
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From: Australia
Originally posted by 350zDCalb
nothing against aps, but it seems coincidental that as more time passes, every new "discovery" is addressed by APS
nothing against aps, but it seems coincidental that as more time passes, every new "discovery" is addressed by APS
Originally posted by 350zDCalb
maybe they are just that good, or maybe they like to promote their kits and try to calm down any of those who may be leary to go FI after all of the engien failures (i know there are no reported aps tt 350z failures as of YET)
maybe they are just that good, or maybe they like to promote their kits and try to calm down any of those who may be leary to go FI after all of the engien failures (i know there are no reported aps tt 350z failures as of YET)
Originally posted by 350zDCalb
first...crank angle sensor prob---they have it covered...
first...crank angle sensor prob---they have it covered...
Originally posted by 350zDCalb
now, the new oil THEORY (capitalized because no one knows for sure)..well, hmmm, ain't that special, they already had the huge-a$$ oil pain that has that base covered as well..
now, the new oil THEORY (capitalized because no one knows for sure)..well, hmmm, ain't that special, they already had the huge-a$$ oil pain that has that base covered as well..
Peter
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From: Australia
Originally posted by kosmic
I'm not saying "They've found the holy grail" but the theory makes sense and is fairly well supported by the experiences of others so far. Only time will tell...
I'm not saying "They've found the holy grail" but the theory makes sense and is fairly well supported by the experiences of others so far. Only time will tell...
Once the big end bearing has spun it's all over for the con rod very quickly, the con rod will either bend or break and the crankshaft journal will be badly damaged...........this is a basic fact that I learnt in the first year of my trade.
Seems to me that if this engine oil starvation problem is sorted by a well baffled oil pan, the problem will be resolved and many engines will be protected from premature big end/con rod failure, certainly worth looking into this issue thoroughly.
Given the thousands of $$$$ that some guys are investing into their engines surely a little time and effort on this issue could pay high dividends. Food for thought.
Thanks
Peter
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From: Atlanta
I don't know how likely this is to occur on stock rods under boost, but it looks like fretting of the big end bearings is a possible cause of bearing wear. If the bearing housing of the con rod is flexing under the new found torque, then the bearing will not be properly supported and result in bearing damage.
http://www.dana.com/Automotive_Syste...ing%20rev.aspx
How likely are bearings to be damaged after a con rod snaps, assuming the bearing was not the cause of the damage and the bearing housing does not rip apart? Can anything be determined from the carnage after the fact, or is there so much damage you can no longer tell?
--
Jeff
http://www.dana.com/Automotive_Syste...ing%20rev.aspx
How likely are bearings to be damaged after a con rod snaps, assuming the bearing was not the cause of the damage and the bearing housing does not rip apart? Can anything be determined from the carnage after the fact, or is there so much damage you can no longer tell?
--
Jeff
Baffling wll not correct oil stavation issues under normal straight line driving conditions.
Believe me Peter, I really like the APS oil pan, and I putting one on my car for sure.
Assuming your theory on the spun bearing is correct, its highly unlikely that a baffled oil pan will correct the problem for most people.
Believe me Peter, I really like the APS oil pan, and I putting one on my car for sure.
Assuming your theory on the spun bearing is correct, its highly unlikely that a baffled oil pan will correct the problem for most people.
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From: Australia
Originally posted by westpak
I agree with Todd, it just seems convenient that the Theory is that oil is the problem and now he has people clamoring for an oil pan group buy, he is good, playing people here like puppets.
I agree with Todd, it just seems convenient that the Theory is that oil is the problem and now he has people clamoring for an oil pan group buy, he is good, playing people here like puppets.
I have no interest in this other than trying to help some forum guys save their engine from unnecessary damage, this high rate of engine failure/rod failure is not good for the entire industry and certainly a real shame for the owner of the car.
Originally posted by westpak
It is hard to put a finger on such a theory with so many variables.
It is hard to put a finger on such a theory with so many variables.
Either way it's your choice to consider the facts and then make your own decision to invest in a APS (or other brand) of oil pan.
Thanks
Peter
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From: Australia
Originally posted by 350zDCalb
and again, this is not anti-aps or anti-peter...sounds like a great guy to me- just interesting, that's all...
and again, this is not anti-aps or anti-peter...sounds like a great guy to me- just interesting, that's all...
I just hope that this thread raises the awareness of the potential engine damage that can be caused through oil starvation, I may be wrong and if I am no harm done.
I still believe that the entire oil starvation issue is worth some serious investigation.
Thanks
Peter
Peter, myself, and my machinist examined my con rod bearings closely, and there were no signs of oil starvation or detonation. I'll try to post some pics later when I get a chance to snap off some good photos. And I had the crappy basic greddy oil pan...first generation version which was a stock pan with fittings welded onto it.
What would cause my bearings to be perfect, and others to be ruined? And I ran my car at 8.5psi for about 14,000 miles....pretty aggressively to boot.
In addition to an upgraded oil pan, I would be looking to add an upgraded radiator, and an oil cooler.
What would cause my bearings to be perfect, and others to be ruined? And I ran my car at 8.5psi for about 14,000 miles....pretty aggressively to boot.
In addition to an upgraded oil pan, I would be looking to add an upgraded radiator, and an oil cooler.
Originally posted by APS
Thanks and I believe that you're not anti APS and I can understand you being a little sceptical on this con rod/bearing failure issue.
I just hope that this thread raises the awareness of the potential engine damage that can be caused through oil starvation, I may be wrong and if I am no harm done.
I still believe that the entire oil starvation issue is worth some serious investigation.
Thanks
Peter
Thanks and I believe that you're not anti APS and I can understand you being a little sceptical on this con rod/bearing failure issue.
I just hope that this thread raises the awareness of the potential engine damage that can be caused through oil starvation, I may be wrong and if I am no harm done.
I still believe that the entire oil starvation issue is worth some serious investigation.
Thanks
Peter
you are definately a good guy...i feel bad if i came across in the wrong way...
it's just, finally, i spend a ton of money, plan a build up very carefully, think i have taken the most important safety precautions...anf then..BOOm, another theory comes out..and now i have to shuffle to get another part...on one side..i am greatful to all of you guys always thinking, always planning for future problems so they can be prevented...and on the other hand..it is frustrating in that now after thinking i could sleep at night with my current setup-not worrying about another failure, this again is not the case...i am just venting in that this is a neverending process...but i knew that when i got into this whole project.
so, peter...please continue with your feedback, and like i said, i will be buying an APS oil pan too !
you can probably appreciate some of the skepticism though, right? anybody can come on this board and start a scare and get all of us who are doing big rebuild projects to purchase additional products- at this point i get the feeling that you are really just being genuine.
TODD
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From: Australia
Originally posted by going deep
As far as the Oil theory is concerned....
I am confident that the engineers at APS are some of the best in the world when it comes to R and D of engines. But it seems to me to make such bold statements about peoples engines blowing without seeing all the evidence. Its kind of like being a airplane crash investigator and being at home watching the news and seeing a 1 min reel of some footage of a crash site. Then, boldly pointing out the flaw that caused this plane to crash. That is exactly whats happening here.
Everyone that goes FI needs to remember that this is YOUR Z and don't let anyone try to put your worst fears to rest. You need to be informed and hope for the best, but make sure you plan for the worst.
As far as the Oil theory is concerned....
I am confident that the engineers at APS are some of the best in the world when it comes to R and D of engines. But it seems to me to make such bold statements about peoples engines blowing without seeing all the evidence. Its kind of like being a airplane crash investigator and being at home watching the news and seeing a 1 min reel of some footage of a crash site. Then, boldly pointing out the flaw that caused this plane to crash. That is exactly whats happening here.
Everyone that goes FI needs to remember that this is YOUR Z and don't let anyone try to put your worst fears to rest. You need to be informed and hope for the best, but make sure you plan for the worst.
I think it's great that guys like yourself are building some lovely engines with forged internals and pushing the power boundaries, more power to you.
I guess my point is (if I'm correct with the oil starvation theory) the very best engine with a billet crankshaft and titanium con rods, etc, etc, will fail if these components are starved for engine oil.
A stock Nissan con rod or the very best forged con rod both require a reliable oil supply system, a baffled oil pan can reduce or eliminate oil starvation under high G forces, a small investment when you consider the total cost of a built engine.
Thanks
Peter
Nissan specifications allow from .001 to .0025 inch clearance between the crank journal and rod bearing.
Possibilities:
1. Manufacturing and assembly did not make it that way.
2. Bearing composition might vary.
3. Those engines that have the .001" clearance might be more prone to failure than those at .0025.
This problem was common on Ford 351M and 400M engines. Their bottom ends were notorious for failure. The cause was low oil pressure under certain circumstances. The solution was a oil restrictor that limited how much oil went up to the heads, valves, and camshaft.
There are a lot of big V8 racing engines that utilize oil (passage) restrictors because of this problem.
Possibilities:
1. Manufacturing and assembly did not make it that way.
2. Bearing composition might vary.
3. Those engines that have the .001" clearance might be more prone to failure than those at .0025.
This problem was common on Ford 351M and 400M engines. Their bottom ends were notorious for failure. The cause was low oil pressure under certain circumstances. The solution was a oil restrictor that limited how much oil went up to the heads, valves, and camshaft.
There are a lot of big V8 racing engines that utilize oil (passage) restrictors because of this problem.
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From: Australia
Originally posted by gq_626
But as stated by several memebers, there are a myriad of different variables that can contribute to engine failure.
But as stated by several memebers, there are a myriad of different variables that can contribute to engine failure.
Originally posted by gq_626
Is oil temp and starvation one of the them? Certainly could be.
Is oil temp and starvation one of the them? Certainly could be.
That said I agree there are many issues that can cause rod failure other than oil starvation (like high engine rpm as only one example) and I believe that pointing out this issue (oil starvation) will help many of the guys who have invested lots of dollars into forged engines and also for the guys running stock engines.
Originally posted by gq_626
Is bad tuning one of the them?
Is bad tuning one of the them?
Bottom line this issue of oil starvation is just another important issue to understand and avoid if long term engine operation is to be expected, hope this helps the guys.
Thanks
Peter