Official S65 Bearing Specification/Clearance Wiki

[Green-Eggs]

Originally Posted by BMRLVR

My 100% stock long block (that will eventually be my stroker) had brand new 702/703 bearings and oem hardware installed and torqued to spec then a high precision flow meter and pressure transducer was fitted and the whole setup has been put in RG's car and driven around and data-logged for the last 6 months in all types of conditions. We have literally millions of lines of data on oil pressure, flow, temperature, throttle position, MAP pressure, RPM, speed, distance travelled, etc and all this data is correlated in a spread sheet and timestamped with box coordinates.

To be exact, as of April 09, 2016, our test car has been logged for: 227 days, 4866.79 miles, 287 engine starts, 107 hours, 56 minutes, 37 second engine running time; 3,885,969 data log events, with 104,921,163 individual pieces of data collected...

One thing I can tell you from all of this data is that the pump in the S65 has lots of headroom where flow is concerned, and in-fact, flows next to no oil <1 GPM at idle and 2-3 GPM at steady cruise yet the pressure stays constant (tight bearing clearance causing low flow? Maybe). However, when throttle position is changed and RPM's are increased and the VANOS units require lots of oil flow to phase the cams, the pump jumps up to >10 GPM.

Yes, the data logs show this to be true.

[BMRLVR]

Originally Posted by swamp2

There is much more to a proper functioning bearing than just basic flow and pressure... Thermal effects are very important. Higher shear and frictional losses at higher rpm (more power per unit time is produced) demand an increased oil flow rate as to prevent bearings from exceeding an operating temperature limit.

Absolutely correct swamp, but I didn't want to get into a huge post...... Even saying what I said it got fairly long...... I was on my phone out with my wife.

[Sneaky Pete]

Originally Posted by BMRLVR

Now I know you are going to try and pick apart my statement above regarding excessive leakage in any of the components fed in the hydraulic system causing pressure drop, and then, you are going to try and relate it to higher clearance bearings causing pressure drop

You once wrote:

Originally Posted by BMRLVR

"The oil pressure in the S65 should be close to continuous across the RPM range (at operating temperature) regardless of RPM once it comes off of Idle"

Yet you can see from the graph you posted, the large variations in flow and oil pressure even at mostly medium revs.
Increasing the RB clearance with the potential to reduce the pressure of the oil film, may or may not have a negative impact...collecting data from a couple of sensors is not going to tell you either way.

[CSBM5]

Originally Posted by BMRLVR

While I do agree with you partially, it is not 100 % correct. You need more system pressure as RPM increases because of the reasons you stated. If the bearing was sealed what you state is true, but since journal bearings in an ICE are not sealed pressure must be increased as RPM's increase. Please read my reasons why below.

As RPM increases so does the load on the hydrodynamic wedge. As the load increases, the wedge gets thinner and also increases it's pressure. This increase in pressure (in the hydrodynamic wedge or bearing not engine oil pressure) tries to force the oil out of the bearing and it in fact does. This forcing of the oil out of the bearing is why most engines builders like to see oil pressure increase proportionally to engine RPM........ Generally speaking most engine builders look for a minimum of 10 PSI increase in oil pressure per 1000 RPM to ensure all bearings in the engine remain adequately supplied with oil so the hydrodynamic lubrication is maintained.

We're talking about the same thing, but you're missing my point which I completely covered with flowrate -- that is what is required, not pressure.

[BMRLVR]

Originally Posted by CSBM5

We're talking about the same thing, but you're missing my point which I completely covered with flowrate -- that is what is required, not pressure.

I get your flow rate statement perfectly, but, the flow must increase with RPM because the additional load forces more oil out of the bearing and additional flow must be engineered in as make-up for this oil lost. Since total system leakage is going to stay static regardless of RPM and the system leakage ultimately controls pressure, the pressure will have to increase with RPM to maintain the adequate flow you are referring to.

P.S.: Great exchange we are having here. It is really nice to be able to debate without having anyone get offended

[OM VT3]

Originally Posted by Sneaky Pete

Who knows - I've seen oil pressure graphs for different oils (on the S65 platform) and they have different peak and average oil pressures.

I'm not sure anybody's going to believe you with your history as SP and SFP of making up your own data for your personal vendetta. Now you claim to have this mythical data that's never been seen by anybody else and never been posted and never been verified by anybody else. Why not post it and let people judge it for themselves? It's like you keeping repeating that 2013 data shows a decrease in engine failures when we all know your previous data as SFP showed the opposite; and when you say there's no UK failures when we've all read about three or four of them. SFP got busted omitting data from his spreadsheet; gotta wonder if that same selective memory is what's going on here.

[Doc Oc]

Originally Posted by bigsurge

Im just gonna attempt to change the subject here...

How many of you guys that installed VAC bearings made sure that the material was sanded of from the parting lines ?

do most shops know to do this ?

Fyi Vac told me to install them straight up without sanding.

[Sneaky Pete]

Originally Posted by OM VT3

I'm not sure anybody's going to believe you with your history as SP and SFP of making up your own data for your personal vendetta. Now you claim to have this mythical data that's never been seen by anybody else and never been posted and never been verified by anybody else. Why not post it and let people judge it for themselves?

LOL And the ole shill poster himself is back.
Classis RG - posting unsubstantiated lies about other forum users.
Didn't that get you banned last time?

Anyway, if you paid attention you would have seen it yourself.
http://www.m3post.com/forums/showthread.php?t=1218175

[kawasaki00]

Originally Posted by Doc Oc

Fyi Vac told me to install them straight up without sanding.

And that is bad advice because the crush numbers are calculated from the manufacturer without the coating.
If you know what you are doing it should always be removed.

[pbonsalb]

Originally Posted by Sneaky Pete

LOL And the ole shill poster himself is back.
Classis RG - posting unsubstantiated lies about other forum users.
Didn't that get you banned last time?

Anyway, if you paid attention you would have seen it yourself.
http://www.m3post.com/forums/showthread.php?t=1218175

For such a new member -- January of 2016 -- you have an exceptional knowledge of what has gone on here.

[Sneaky Pete]

Originally Posted by pbonsalb

For such a new member -- January of 2016 -- you have an exceptional knowledge of what has gone on here.

Been following this story for a long time.

[Doc Oc]

Originally Posted by kawasaki00

And that is bad advice because the crush numbers are calculated from the manufacturer without the coating.
If you know what you are doing it should always be removed.

Perhaps their custom designed bearings take that into account? I emailed them after seeing your post.....no response yet

[pbonsalb]

Originally Posted by Sneaky Pete

Been following this story for a long time.

Yes, we know, sneaky.

[OM VT3]

Originally Posted by pbonsalb

Yes, we know, sneaky.

Lol

[Sellout]

Originally Posted by Doc Oc

Perhaps their custom designed bearings take that into account? I emailed them after seeing your post.....no response yet

custom designed? aren't they oem bearings with a coating added?

[Doc Oc]

No, it is a custom designed bearing and even with the coating it offers more clearance than any bearing outside of the BE's. You are thinking of their first attempt several years ago which was just a stock bearing coated.

[bigsurge]

Originally Posted by Doc Oc

No, it is a custom designed bearing and even with the coating it offers more clearance than any bearing outside of the BE's. You are thinking of their first attempt several years ago which was just a stock bearing coated.

Funny part is Malek and Harrop have both taken apart engines that had VAC bearings installed after supercharger upgrades and they looked mint even though they were decreasing clearances and there was speculation that the ARP bolts made them out of round.

[Doc Oc]

Originally Posted by bigsurge

Funny part is Malek and Harrop have both taken apart engines that had VAC bearings installed after supercharger upgrades and they looked mint even though they were decreasing clearances and there was speculation that the ARP bolts made them out of round.

I saw that....39k miles on them right? Kind of goes against the commonly accepted theory here.....

[Green-Eggs]

Originally Posted by bigsurge

Funny part is Malek and Harrop have both taken apart engines that had VAC bearings installed after supercharger upgrades and they looked mint even though they were decreasing clearances and there was speculation that the ARP bolts made them out of round.

That's not speculation, that's fact. The ARP bolts have been measured and documented at the BE Bearings wiki to create bore distortion (extra clearance) on both brand new factory rods, and used (in car) rods. The used rods created nearly double the bore distortion as the new factory rods using the same bolts at the same torque spec.

You can read more about bore distortion and see the measurements and the graphs for yourself if you visit the bebearings.com web site and look at the FAQ. Scroll down until you see the links to rod bolt measurements.

Originally Posted by Doc Oc

I saw that....39k miles on them right? Kind of goes against the commonly accepted theory here.....

How so? When the bore distortion increases to clearance by more than 0.001 inch (more extra clearance than BE Bearings offer), and you take them apart and find the bearings looking fine, then I'm not following how that contradicts the common theory that too little clearance is wearing down the bearings.

We've redone the bearings on two supercharged motors with VAC coated bearings, one with only 1500 miles, and the other maybe 15000 miles. Both engines used factory bolts which don't create the bore distortion. The bearings with 1500 miles were already showing scuff marks and wear marks and one or two streaks in them. The other ones also showed wear, but I don't remember them as much as I do the ones with 1500 miles on them. I still have both sets here somewhere.

[bigsurge]

Originally Posted by Green-Eggs

We've redone the bearings on two supercharged motors with VAC coated bearings, one with only 1500 miles, and the other maybe 15000 miles. Both engines used factory bolts which don't create the bore distortion. The bearings with 1500 miles were already showing scuff marks and wear marks and one or two streaks in them. The other ones also showed wear, but I don't remember them as much as I do the ones with 1500 miles on them. I still have both sets here somewhere.

That makes perfect sense, so best case scenario would be BE bearings or VAC with extra clearance along with OEM rod bolts or are there aftermarket bolts that can be torqued to spec ?

[Doc Oc]

Originally Posted by Green-Eggs

That's not speculation, that's fact. The ARP bolts have been measured and documented at the BE Bearings wiki to create bore distortion (extra clearance) on both brand new factory rods, and used (in car) rods. The used rods created nearly double the bore distortion as the new factory rods using the same bolts at the same torque spec.

You can read more about bore distortion and see the measurements and the graphs for yourself if you visit the bebearings.com web site and look at the FAQ. Scroll down until you see the links to rod bolt measurements.



How so? When the bore distortion increases to clearance by more than 0.001 inch (more extra clearance than BE Bearings offer), and you take them apart and find the bearings looking fine, then I'm not following how that contradicts the common theory that too little clearance is wearing down the bearings.

We've redone the bearings on two supercharged motors with VAC coated bearings, one with only 1500 miles, and the other maybe 15000 miles. Both engines used factory bolts which don't create the bore distortion. The bearings with 1500 miles were already showing scuff marks and wear marks and one or two streaks in them. The other ones also showed wear, but I don't remember them as much as I do the ones with 1500 miles on them. I still have both sets here somewhere.

I wasn't talking about the tolerance theory, sorry if I wasnt clear. I was talking about the idea that those oem coated bearings weren't a good option because they decreased clearance.

Question though: If the ARP bolt causes the bore to go out of round, then wouldnt't clearance increase in certain areas but decrease in others? Bore distortion can't create an extra thousandth of clearance all the way around, that doesn't seem possible.

[LangRacingDevelopment]

Originally Posted by Doc Oc

If the ARP bolt causes the bore to go out of round, then wouldnt't clearance increase in certain areas but decrease in others? Bore distortion can't create an extra thousandth of clearance all the way around, that doesn't seem possible.

If it's looser at the top and bottom it will be proportionally looser at the parting line yes.