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when are 3/4 grooved main bearings needed for bbc ?

General engine tech -- Drag Racing to Circle Track

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engineguyBill
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Re: when are 3/4 grooved main bearings needed for bbc ?

Post by engineguyBill » Mon Dec 02, 2019 1:56 pm

The 'length" of the groove in the upper shell is not critical as long as the groove is 180 degrees or less. The function of the groove is to deliver oil to the thin areas of the shells (at the parting line) in order to form an oil wedge in the proper location which is dependent upon the crankshaft rotational direction. Automotive engine crankshaft bearings are designed with an elliptical ID shape for this reason. Simple as that . . . .
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Re: when are 3/4 grooved main bearings needed for bbc ?

Post by ClassAct » Tue Dec 03, 2019 9:49 pm

Warp Speed wrote:
Sun Dec 01, 2019 8:22 am
modok wrote:
Sun Dec 01, 2019 2:45 am
Oh, ok, third oil galley.
Maybe
Winner winner chicken dinner! :wink:
Something the SBM and Pontiac engines that he references, are missing also. :-k
Aka, an efficient, quality supply to the bulkhead feeds.................

You are still wrong. Figure I out warp. The lifters don't matter. I can block the oil to the lifters and it STILL doesn't fix the issue.

Damn you are stubborn.

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Re: when are 3/4 grooved main bearings needed for bbc ?

Post by ClassAct » Tue Dec 03, 2019 9:53 pm

I guess I need to make a video. It's so simple it's stupid. Priority main oiling has ZERO to do with it. Don't tell me 3 passages makes a pinch of shit of difference. It doesn't.

Warp had trouble posting a SBM oiling system. I know what the oiling system looks like.

I can tell you that I charge 1500 bucks to fix a Chrysler. 2000 if they want it hidden. You can't say any difference than the location of the oiling holes. That's the difference.

Period.

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Re: when are 3/4 grooved main bearings needed for bbc ?

Post by ClassAct » Tue Dec 03, 2019 9:59 pm

Rick! wrote:
Sun Dec 01, 2019 10:15 am
ImageImage

Main priority cleveland: https://www.tmeyerinc.com/product/track ... and-block/

Then there's this: https://patents.google.com/patent/US8307804B2/en


I don know how a jap engine has any correlation to this discussion, but I can read that later.

Thank you for the like to the track boss engine. Look very close at the pictures. You will see the dude who produces that block KNEW exactly WTF I'm talking about and he FIXED it.

Took all of 10 seconds looking at the pictures. So simple. But warp doesn't know it or whatever so I wrong. Hilarious.

The track boss PROVES I correct and the dude making those gets it. And priority main oil doesn't have jack shot to do with oiling the rods. Period.

I stand vindicated by the very nice link RICK! provided. Thank you sir.

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Re: when are 3/4 grooved main bearings needed for bbc ?

Post by swampbuggy » Tue Dec 03, 2019 11:21 pm

Here is one fact that we can ALL agree on i am sure. The ((("MOST"))) important part of the engine to ALWAYS have quality oiling IS the main and rod insert bearings!. This is WHY making the main bearing bulkheads FIRST and TOP priority with a dedicated main oil gallery IS so important regardless of where the holes are in the block and or crank. Mark H.

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Re: when are 3/4 grooved main bearings needed for bbc ?

Post by cjperformance » Tue Dec 03, 2019 11:42 pm

Warp Speed wrote:
Sat Nov 30, 2019 11:18 pm
ClassAct wrote:
Sat Nov 30, 2019 10:44 am
Warp Speed wrote:
Sat Nov 30, 2019 8:05 am


#-o


I hope you are "done", because your really making yourself look foolish!

Glad you think so. I could find probably 10 well know authors who wrote books on Chrysler engines and virtually every one of them calls for the exact same mods as the link posted above.

All of them are bandaids and never fix the issue.

Like I said...I learned from a guy who was paid to find a solution. He was a hydraulics engineer. The guy who paid him was running Modified Eliminator and was tired of two things: being RPM limited and loosing Rod bearings. So he hired this guy, the hydraulics engineer. He figured it out. And the guy who paid for it sent all that information back to Chrysler so maybe, just maybe, they would look at fixing the issue since the much vaunted X block had run its course and was long overdue for an update. Like everything else, Chrysler didn't care. And as a result, all of the R series blocks from Chrylser still have the oil timing wrong. I was told some of last blocks made had it corrected, but I've never seen one personally. Not even in pictures.

The funny thing is, when Kent Ritter started making blocks he move the oil feed hole. Hmmmmmmmmmmmmm.

You still haven't explained (and I know you won't because evidently you can't) why a SBC without priorority main oiling will oil the rods literally forever and the Chrysler, Ford, Pontiac etc won't do it. And don't say it's because of leaks around the lifters as that is an easy fix that doesn't fix anything. It just moves the RPM up before the catastrophe happens. Like full groove mains.

I'm waiting.
As I asked above, but will ask again, and it will answer your question. What is the one difference between a 351c oiling system, and the 351w oiling system? I'll give you a hint, both the 302/351w have it, and so does the sbc........
Other than that, the 351w is almost identical, including this "advanced block timing" your hung up on. Yet we spin those regularly to 8500, making 1500+whp.........?
A "priority main" oil gallery, in the case of a ford- fed from the oil filter at the front this gallery feeds the mains, rods and cam bearings before it then branches off at the rear to feed the lifters/top end.
No oil dodging moving/rotating lifters as well as the multiple bleed off areas this creates along the way.
Craig.

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Re: when are 3/4 grooved main bearings needed for bbc ?

Post by cjperformance » Tue Dec 03, 2019 11:43 pm

Oops, just realised i didnt come in on the last page :lol:
Craig.

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Re: when are 3/4 grooved main bearings needed for bbc ?

Post by Warp Speed » Wed Dec 04, 2019 4:47 am

ClassAct wrote:
Tue Dec 03, 2019 9:49 pm
Warp Speed wrote:
Sun Dec 01, 2019 8:22 am
modok wrote:
Sun Dec 01, 2019 2:45 am
Oh, ok, third oil galley.
Maybe
Winner winner chicken dinner! :wink:
Something the SBM and Pontiac engines that he references, are missing also. :-k
Aka, an efficient, quality supply to the bulkhead feeds.................

You are still wrong. Figure I out warp. The lifters don't matter. I can block the oil to the lifters and it STILL doesn't fix the issue.

Damn you are stubborn.
Damn you are clueless! :lol:
Maybe you should try a different hobby?

I will ask AGAIN, why doesn't a 351w have the same problem as a 351c, when they have the same "block timing" that you preach is the root of all evil?!?
I mean neither is an optimum design, but why?!?

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Re: when are 3/4 grooved main bearings needed for bbc ?

Post by BobbyB » Wed Dec 04, 2019 6:28 am

swampbuggy wrote:
Tue Dec 03, 2019 11:21 pm
Here is one fact that we can ALL agree on i am sure. The ((("MOST"))) important part of the engine to ALWAYS have quality oiling IS the main and rod insert bearings!. This is WHY making the main bearing bulkheads FIRST and TOP priority with a dedicated main oil gallery IS so important regardless of where the holes are in the block and or crank. Mark H.
There is a bunch of gibberish & chest pounding in this thread. I would like to understand more of the technical elements of what goes on in an engine and why some engines have more trouble than others, but I can’t get past Warp & Class Act disrespecting each other.
So, what the heck is “Quality Oiling”( I think Warp used that term first.) Does Stewart Warner or autometer make a quality oil gauge?
What the heck happens if any ohv engine breaks a pushrod & blows a lifter out and oil flow to an unbushed lifter hole goes sky high?
Isn’t all this stuff just branch circuits in a simple hydraulic system...just one pump...right?

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Re: when are 3/4 grooved main bearings needed for bbc ?

Post by Warp Speed » Wed Dec 04, 2019 7:27 am

BobbyB wrote:
Wed Dec 04, 2019 6:28 am
swampbuggy wrote:
Tue Dec 03, 2019 11:21 pm
Here is one fact that we can ALL agree on i am sure. The ((("MOST"))) important part of the engine to ALWAYS have quality oiling IS the main and rod insert bearings!. This is WHY making the main bearing bulkheads FIRST and TOP priority with a dedicated main oil gallery IS so important regardless of where the holes are in the block and or crank. Mark H.
There is a bunch of gibberish & chest pounding in this thread. I would like to understand more of the technical elements of what goes on in an engine and why some engines have more trouble than others, but I can’t get past Warp & Class Act disrespecting each other.
So, what the heck is “Quality Oiling”( I think Warp used that term first.) Does Stewart Warner or autometer make a quality oil gauge?
What the heck happens if any ohv engine breaks a pushrod & blows a lifter out and oil flow to an unbushed lifter hole goes sky high?
Isn’t all this stuff just branch circuits in a simple hydraulic system...just one pump...right?
If thats how you feel, I would look elsewhere for the answers to your questions, instead of just adding to the drama!
Btw, your above mentioned manufacturers do sell descent "quality oil gauges". An "oil quality gauge", is called a coriolis meter! :wink:
And an engine oiling system is anything but a "simple hydraulic system".
IMO..............which apparently I would be better off keeping it to myself in the future! :-#

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Re: when are 3/4 grooved main bearings needed for bbc ?

Post by ptuomov » Wed Dec 04, 2019 7:49 am

Does anyone have a Coriolis Meter aka fluid mass flow meter on a running car? That would be a bad a$$ way to debug a wet dump engine!

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Re: when are 3/4 grooved main bearings needed for bbc ?

Post by swampbuggy » Wed Dec 04, 2019 9:02 am

Warpspeed: please do not remain silent, i and some others take what you say as knowledge from experience and take it to heart :) . I for one GREATLY appreciate you taking your time to post on this forum. To anybody who has not viewed the article produced by Mahle, i would recommend that you read it. It is on page 12 and was posted by Ptuomov. Mark H.

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Re: when are 3/4 grooved main bearings needed for bbc ?

Post by Kevin Johnson » Wed Dec 04, 2019 10:09 am

ptuomov wrote:
Mon Dec 02, 2019 11:53 am
I found this interesting, not from rod oiling perspective but from the perspective of the potential benefits of shortening the main bearing groove:

https://www.mahle-aftermarket.com/media ... tb2051.pdf

Goes without saying that sufficient rod oiling is more important than picking up some efficiencies from the shorter groove, but if the rod bearing gets oiled with a shorter groove, there's a benefit from using a shorter groove.

As a note, I think the horsepower loss is in the units of what's lost in friction etc. in the 180-degree grooved main bearing. It's obviously not in the units of engine power. The direct gain from shortening the groove from 180 degrees to 140 degrees is minor, so I'd only consider this if the shorter groove allows one to change other main bearing design parameters (maybe a smaller main journal diameter?) that then give further gains.
The Mahle article does not take into account rho, or oil density. That would be related to oil quality as Jay has mentioned. I believe the reason for the extended grooves (somewhat beyond 180 degrees) is to accommodate cross-main oil drillings in the sense that the intensity of the puise or flow reversal is attenuated. A good SAE paper to read that I have recommended for many years is 932785 http://papers.sae.org/932785/

I will append one page that explains this:
SAE_932785_OIL_PULSE.jpg

Aside: Even Meernik's paper assumes a rho of 1g cm^3 when a typical neat motor oil is more in the range of .87g cm^3. Be careful of assumptions when dealing with the effects of aerated oil. Note carefully that aerated oil has multiple senses which can co-exist in situ.
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Re: when are 3/4 grooved main bearings needed for bbc ?

Post by ClassAct » Wed Dec 04, 2019 11:53 am

Warp Speed wrote:
Wed Dec 04, 2019 4:47 am
ClassAct wrote:
Tue Dec 03, 2019 9:49 pm
Warp Speed wrote:
Sun Dec 01, 2019 8:22 am


Winner winner chicken dinner! :wink:
Something the SBM and Pontiac engines that he references, are missing also. :-k
Aka, an efficient, quality supply to the bulkhead feeds.................

You are still wrong. Figure I out warp. The lifters don't matter. I can block the oil to the lifters and it STILL doesn't fix the issue.

Damn you are stubborn.
Damn you are clueless! :lol:
Maybe you should try a different hobby?

I will ask AGAIN, why doesn't a 351w have the same problem as a 351c, when they have the same "block timing" that you preach is the root of all evil?!?
I mean neither is an optimum design, but why?!?


Post up the oil schematic for both. You keep going back to that and I keep asking why does the SBC oil when others don't. And you say it's the third oil gallery. I say it's not, because it isn't. And again, for all those who are having trouble getting the concept down, nowhere have I said, not a SINGLE TIME have I said that priority main oiling wasn't the way to do it. I've said priority main oiling doesn't fix a Rod bearing oiling issue. That's pretty simple and self evident.

You tell me how can the main bearings look brand new and the Rod bearing are BLUE? The oil is at the main bearing. Has to be. Or they'd be blue as well. It's because at some point, at some RPM/load, bearing diameter, oil hole clocking, the Rod bearing won't get enough oil at the correct TIME. Period. Priority main oiling doesn't fix this. Bushing the lifter bores will help, just like a full groove main, but the point will come when even those things aren't enough.

This isn't hard.

Like I said for all the doubters just grab a SBM block and crank and a SBC block and crank and get out your degree wheel. Look at the oil feed hole in the main bearing. It will be the same on both cranks. Exactly the same. Then look at the oil feed holes in both blocks. You'll quickly see that the SBC is at 12 o'clock and the SBM is about 11 o'clock.

Put the crank in the SBC and mark on the crank where the oil feed hole is. Mount your degree wheel and see when the hole in the block lines up with the hole in the crank on the SBC. The piston will be ~ 70* ATDC. Warp says 90 but my memory says 70.

Either way, do the same on the SBM and you'll see the oil gets to the rods on the SBM way too early. IIRC it's about 58 or so degrees ATDC, but it's been a while since I checked one. That means the SBM is advanced by roughly 12 degrees.

And before all the naysayers and nattering nabobs say it's only 12 degrees...that ain't shit, run out and add 12 degrees total to your engine and then go out and throw a load on it and see how long it lasts.

That's why bushing the lifter bores HELPS. Doesn't fix it, but it delays the RPM/load at which oil starvation occurs. Just like a full groove main bearing. You are getting SOME oil to the rods all the time. But again, at some RPM/load that won't be enough. And the Rod bearings don't get ENOUGH oil at the correct TIME and then it's all over.

So yes, 10-12 degrees of oil timing matters.

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Re: when are 3/4 grooved main bearings needed for bbc ?

Post by Kevin Johnson » Wed Dec 04, 2019 12:47 pm

A SBC and SBM can have the sump reservoir in different locations. Many SBMs have a front sump and during drag racing with a stock type pan it is more likely that the pickup opening will vortex to the surface and/or that the oil displaced to the rear will be churned by the rotating assembly. During vehicle/motor development with parking or driving on grades this will be noted as well. Yes, I know about front sump Chevy II/Nova oil pans.

The additional air that is whipped into the oil by the rotating assembly cannot all be dissolved by the pump so there are free air bubbles present. A bubble filled fluid being accelerated by the oil passage will have conflicting phase flow paths determined by density. This will delay transit in the passage and could require additional degrees of advance to allow for the outer phase (oil) to successfully reach the rod journal. That would be determined by empirical testing under the expected operating conditions. Different companies or even divisions within the same company will generate different solutions.

If you alter the conditions that the vehicle/engine operates under then changes could be needed. Obviously, successful changes have been found by authors in this thread.

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