That's what I use when building or overhaul. Half a thousand per inch.
The effects of 5W30 through small passages
- Thread starter ARB1977
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I'm good with an idiot proof 3.5 hths, 10cSt @100c, ect.
We know 10,000 to 30,000 mile oci don't immediately kill engines, plenty of Nissans out there with 100,000 to 200,000 mile engines with not nearly enough oil changes.
I only change my Nissans oil about every 30,000 miles lol.
Good point, but I'd think a big engineering house within Toyota would model that and see how it would impact the bearing clearance as it went from extreme cold start to extreme full operating engine temperatures. With today's super computers and modeling tools, I'd think it could be done pretty easily to see how an assembly like that changes as it goes through temperature swings.
That bottom end is about as stiff as you'll ever see. I doubt it.
I agree
The swarf is needing more actual root cause for us 5 WHY? Eng-gah-neeres.
Because swarf could be a direct cause but not the root cause
Really? Hmm. The tear downs I’ve seen it seems smallish.
Four bolts per main cap. Full girdle construction. inserted main caps.
Those inserts are cast into the girdle.
This is racing block technology in a production engine. Note how the oil drainback is routed around the crank to reduce windage.
The windage tray design contributes a non-trivial amount of bottom end stiffness also.
On Cummins engines, we use a "bedplate" which looks like a windage tray. But its purpose is structural for bottom end stiffening, not for oil control per se.
This toyota engine has a similar approach however the shape and thickness of the plate suggest it's more for windage and the structural contribution is secondary. It's just not very stiff by itself. But when you add that to the girdle design and such, it's a really really beefy bottom end, far more so than even the best of the classic muscle car engines.
As it should be, it's making a lot more power per liter.
This is table stakes for a company like Toyota. They have a very robust ALD/FEA workup before a single part ever exists outside the computer. They analysis will include major temperature swings, temperature swings with spec-limit dimensions, temperature swings with spec-limit dimensions at the worst case of possibly assembly, etc.
IN other words, like Cummins does, they are designing to protect for a statistically impossible combination of things like you have the one part in 10,000 with the largest clearance holes, assembled in the worse possible orientation and position on the engine, and then cold started at -40.
It's the engineering version of budgeting for how you will spend the winnings from the lottery ticket you bought that won after buying one ticket in a decade from a randomly chosen state or national lottery.
Other comments on the bottom end design-- note that each crank journal carries only one rod. The crank webs are quite thick, about as wide as the connecting rod. The stroke and crank journal diameter appear to be chosen with significant overlap between rod journal and main journal-- this is an important aspect of crank stiffness and fatigue. Combine a good bit of overlap with thick webs bolted into a really stiff girdle bottom end and you have a recipe for a really robust bottom end.
I appreciate your point, and explaining this. Do you think it’s swarf, then?
I’m trying to find the pix that led me to think it was the block. The crank looks good, though.
I personally think debris is likely to be the most significant contributor, but by no means the sole cause. There’s certainly a design aspect. Because you have to design something you can clean effectively. You have to design some robustness into the manufacturing process.
I think Toyota built the equivalent of an anti-anti-missile missile that shoots itself down sometimes.
You can’t draw from the well of tolerance indefinitely.
All contributory but root cause is not public
^^^ And to add, for a new design after all that kind of computer design and simulation effort there will be some level of hardware testing to validate the design is going to work. This would ultimately work up to be a full blown pre-production engine validation testing putting it through all its paces for every design aspect.
If all engines in the field are not failing, then it's not some engineering design flaw root cause. The next level is possible manufacturing issues that don't result in meeting the engineering design specs. And if manufactured too far outside the specs it could show up as a problem in the field. If that was the case surely Toyota would have focused in and figured that out by now and not go down the left over manufacturing debris road - which would also be a manufacturing & QA issue. You can have the perfect design on paper, but if manufacturing engineers responsible for production, and people operating machines, etc can't meet the specs then it can result in junk.
If the cause is left over debris, then that could make every engine go through the failure process somewhat differently depending on level of debris left behind. Once enough debris starts causing enough damage where it then becomes self feeding, it will snowball into what happened in the engine in post 1. There was a lot of debris found everywhere in that engine, and I bet lots of it was self feeding damage debris.
If all engines in the field are not failing, then it's not some engineering design flaw root cause. The next level is possible manufacturing issues that don't result in meeting the engineering design specs. And if manufactured too far outside the specs it could show up as a problem in the field. If that was the case surely Toyota would have focused in and figured that out by now and not go down the left over manufacturing debris road - which would also be a manufacturing & QA issue. You can have the perfect design on paper, but if manufacturing engineers responsible for production, and people operating machines, etc can't meet the specs then it can result in junk.
If the cause is left over debris, then that could make every engine go through the failure process somewhat differently depending on level of debris left behind. Once enough debris starts causing enough damage where it then becomes self feeding, it will snowball into what happened in the engine in post 1. There was a lot of debris found everywhere in that engine, and I bet lots of it was self feeding damage debris.
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And that's why there are design engineers, test engineers and manufacturing engineers. They all need to collaborate to ensure a design can successfully be designed and manufactured.
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I'm personally not impressed with concept of the all aluminum bedplate of the V35A.
I think the assumptions that it's inherently robust are unfounded.
Note the commonality here
11,000 HP capable BAE Top fuel billet block:
One of the few OEM cast production blocks that have proven to hold upwards of the 3000 HP:
A current production turbocharged V6 doesn't doesn't typically experience main bearing or block failures:
I think the assumptions that it's inherently robust are unfounded.
Note the commonality here
11,000 HP capable BAE Top fuel billet block:
One of the few OEM cast production blocks that have proven to hold upwards of the 3000 HP:
A current production turbocharged V6 doesn't doesn't typically experience main bearing or block failures:
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Some engines that are both 4 bolt plus cross bolted - and going as far as using the oil pan for an extra layer of stiffening can still fail …
I have seen times where you need to slow down using what you already proved up …
Get it right the first time …
I have seen times where you need to slow down using what you already proved up …
Get it right the first time …
That windage tray is just a piece of stamped sheet metal, and isn't really going to add any significant stiffness to the assembly.
The Coyote uses steel main bearing caps on an aluminum block, so the difference in thermal expansion isn't a problem with that engine. It also uses 6-bolt main bearing caps. The stock bottom end is good for around 1000 HP max.
Main bearing caps, made of steel, not aluminum.
Weird how back in the day small block engines with the 4 bolt main caps just hanging off the bottom of the block could handle up to a thousand horses and big blocks could handle up to 2,000.
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