Are stock rods suitable for FI VQ engines?
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Originally posted by nis350ztt
Peter, did you see what 2jzfan said about the baffling? Just wondering what your thoughts on that is.
Peter, did you see what 2jzfan said about the baffling? Just wondering what your thoughts on that is.
Thanks
Peter
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Originally posted by overZealous1
one thing i have not seen anyone touch on yet is machining. what tolerances or process is the factory using. also aluminum going through that many heat cycles is going to shift, especially on a new block. there is the chance of core shift on the main bearings that would produce uneven bearing wear also. v type motors also do not have as much support on the crank shaft as inline motors and having longer distances between main bearings which can lead to crank flexing for guys putting down good power.
also what tolerances does nissan use for checking crank straightness when they build the motor. surely they have specs, but maybe not quite as tight of specs as would need to build a high hp motor. i have seen uneven bearing wear in quite a few of my v8 motors and most were due to core shift, crankout of tolerance for straightness, not giving a seasoned block a line bore or over rev which lead to crank flexing.
one thing i have not seen anyone touch on yet is machining. what tolerances or process is the factory using. also aluminum going through that many heat cycles is going to shift, especially on a new block. there is the chance of core shift on the main bearings that would produce uneven bearing wear also. v type motors also do not have as much support on the crank shaft as inline motors and having longer distances between main bearings which can lead to crank flexing for guys putting down good power.
also what tolerances does nissan use for checking crank straightness when they build the motor. surely they have specs, but maybe not quite as tight of specs as would need to build a high hp motor. i have seen uneven bearing wear in quite a few of my v8 motors and most were due to core shift, crankout of tolerance for straightness, not giving a seasoned block a line bore or over rev which lead to crank flexing.
Thanks
Peter
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Originally posted by jeffw
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.
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.
Originally posted by jeffw
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.
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.
Peter
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Originally posted by gq_626
Baffling wll not correct oil stavation issues under normal straight line driving conditions.
Baffling wll not correct oil stavation issues under normal straight line driving conditions.
Originally posted by gq_626
Believe me Peter, I really like the APS oil pan, and I putting one on my car for sure.
.
Believe me Peter, I really like the APS oil pan, and I putting one on my car for sure.
.
Originally posted by gq_626
Assuming your theory on the spun bearing is correct, its highly unlikely that a baffled oil pan will correct the problem for most people.
Assuming your theory on the spun bearing is correct, its highly unlikely that a baffled oil pan will correct the problem for most people.
It's my humble opinion if you starve the big end bearings of engine oil for even a short period that the chance of spinning the big end bearing in the con rod is dramatically increased, hence very bad damage to the crankshaft journal and con rod failure (bending or breaking the con rod).
Thanks and hope this helps.
Peter
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Originally posted by gq_626
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.
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.
Originally posted by gq_626
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.
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.
Originally posted by gq_626
In addition to an upgraded oil pan, I would be looking to add an upgraded radiator, and an oil cooler.
In addition to an upgraded oil pan, I would be looking to add an upgraded radiator, and an oil cooler.
Peter
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Originally posted by 350zDCalb
peter:
you are definately a good guy...i feel bad if i came across in the wrong way...
peter:
you are definately a good guy...i feel bad if i came across in the wrong way...
Originally posted by 350zDCalb
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
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
Only then did this rod/bearing issue start to make sense to me after viewing a good number of damaged crankshafts and con rods, I'm 99% sure from what I viewed that at least some of the engines have failed due to oil starvation. I certainly did not intend to panic any of the guys to run out and by a hi volume baffled oil pan.
Originally posted by 350zDCalb
...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.
...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.
Originally posted by 350zDCalb
...so, peter...please continue with your feedback, and like i said, i will be buying an APS oil pan too !
...so, peter...please continue with your feedback, and like i said, i will be buying an APS oil pan too !
Originally posted by 350zDCalb
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
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
I don't mind at all if forum guys make their own baffled high volume oil pan and save the $$$ rather than buying a brand name oil pan, promoting oil pans was never in my mind when I started the thread.
Thanks
Peter
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Originally posted by jcn30127
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.
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.
Peter
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Originally posted by 35ounces
APS: Do you guys sell that baffled oil pan seperately ?
APS: Do you guys sell that baffled oil pan seperately ?
Thanks
Peter
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Originally posted by turbo-maxima
what about designing a one piece upper and lower oil pan and you could probabl have a 7 quart one. Like they do for Chevy Small Blocks.
what about designing a one piece upper and lower oil pan and you could probabl have a 7 quart one. Like they do for Chevy Small Blocks.
Thanks
Peter
Man I love the ability of peter to keep his threads alive by answering older posts on the same thread, even ones that were before ones already answered. Nice product promotion, APS keeps popping up, paid sponsor yet?
Oh an we are so sorry for making you gunshy
Oh an we are so sorry for making you gunshy
Originally posted by westpak
Man I love the ability of peter to keep his threads alive by answering older posts on the same thread, even ones that were before ones already answered. Nice product promotion, APS keeps popping up, paid sponsor yet?
Oh an we are so sorry for making you gunshy
Man I love the ability of peter to keep his threads alive by answering older posts on the same thread, even ones that were before ones already answered. Nice product promotion, APS keeps popping up, paid sponsor yet?
Oh an we are so sorry for making you gunshy
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Well, if it's a good product and if it really solves the problem, I don't see a problem if he promotes his oil pan. But there are Maxima guys running nitrous and/or sc on their VQ35 for a while now. If it's a oil problem not a weak con rod problem, why didn't they find out about it first. If it's diagnosed by looking at the bearings, I'm sure some knowledgeable Maxima guys or their engine builder would point it out already.
Originally posted by APS
Of course I can, this thread has taught me a lot and will make me think long and hard before starting a thread like this again...............please be assured that I was not trying to sell oil pans, to the contrary I just got excited about the thought that I had stumbled across the technical possibility of this oil starvation problem.
Thanks
Peter [/B]
Of course I can, this thread has taught me a lot and will make me think long and hard before starting a thread like this again...............please be assured that I was not trying to sell oil pans, to the contrary I just got excited about the thought that I had stumbled across the technical possibility of this oil starvation problem.
Thanks
Peter [/B]
Please keep your thoughts and revelations coming!
Originally posted by jeffw
Could there be a problem of increased torque amplifying torsional vibrations and therefore hurting the bearings? The damping provided by the stock pulley may be insufficient. Also, I imagine engine balance might be an issue (and can only be solved with a rebuild).
Here's a crankshaft vibration damping alternative (don't know if the race series pulley can be used for a daily driver):
http://www.fluidampr.com/sport_compact.htm
--
Jeff
Could there be a problem of increased torque amplifying torsional vibrations and therefore hurting the bearings? The damping provided by the stock pulley may be insufficient. Also, I imagine engine balance might be an issue (and can only be solved with a rebuild).
Here's a crankshaft vibration damping alternative (don't know if the race series pulley can be used for a daily driver):
http://www.fluidampr.com/sport_compact.htm
--
Jeff
Jason