Rod Bearing Replacement - BE vs VAC?

[Andratch]

Hi everyone,

I'm about to do have a local shop replace the rod bearings in my 05. The car is pretty low mileage (51k miles), but I have no knowledge of how it was driven in the past, if they've ever been replaced....so, going on 20 years old, I think replacing them as a proactive measure will give me more confidence as I intend to use it in a few HPDEs and whatnot.

The shop I trust locally recommended BE Clevite bearings. It looks like that's basically an OEM replacement on the bearings, so they'd probably be good for 100k miles or so, which is more than I'll ever drive this car.

With that said, I hear good things about VAC bearings that Turner and others sell.

I may be overthinking this, but if I intend to use the car pretty sparingly and bring it to the occasional HPDE, does it make much of a difference which brand I use? Is there a significant difference between VAC and BE? I can't find many threads with insights on the longevity of the replacement bearings, people just rag on the ones that came in the engine from day 1...

[bmwfnatic]

BMW bearings, BMW bolts...

ARP bolts are acceptable on the earlier M11 engines, not on the later M10 ones, believe there's a Lang blog post about that somewhere.

[Andratch]

BMW bearings, BMW bolts...

ARP bolts are acceptable on the earlier M11 engines, not on the later M10 ones, believe there's a Lang blog post about that somewhere.

Good advice on the ARP's, just found a long thread on this over at m3cutters.

[Nate047]

I have BE Cleavite in my car. VAC as a whole has a dodgy reputation so I dunno if I’d trust their rod bearings or not.

[Sharocks]

Rule of thumb, don't use anything from Philly in your car.

[Andratch]

I have BE Cleavite in my car. VAC as a whole has a dodgy reputation so I dunno if I’d trust their rod bearings or not.

Yeah that seems to be the consensus after a bit more research. I think BE + OEM Bolts sounds like the best combo.

[Slideways]

Redish Motorsport in the UK uses ACL bearings with stock rod bolts. They have multiple videos showing this combination results in factory bearing clearances.

[Altaran]

Redish Motorsport in the UK uses ACL bearings with stock rod bolts. They have multiple videos showing this combination results in factory bearing clearances.

ACL bearings work great. One downside is that their manufacturing tolerances have a higher spread, so I wouldn't trust them to be plug and play.
Just make sure the shop installing them is doing clearance measurements (as any proper engine builder does) and you should be fine.

Gesendet von meinem Pixel 7 mit Tapatalk

[Slideways]

ACL bearings work great. One downside is that their manufacturing tolerances have a higher spread, so I wouldn't trust them to be plug and play.
Just make sure the shop installing them is doing clearance measurements (as any proper engine builder does) and you should be fine.

Gesendet von meinem Pixel 7 mit Tapatalk

They typically measure them with plastigauge as the engine is still in the car. One member on this forum recently rebuilt his engine and measured the same clearance for all the rod bearings as they did in the Redish videos. Most of these aftermarket bearings come packaged together, so unless there is major clearance issue, you have to install the set even if there is a minor variation in clearance. From all the examples online, ACLs tend to be in the middle of the spec. Redish measured a set of OE bearings and they were on the tighter side and most people install those without checking.

[tlow98]

BMW bearings, BMW bolts...

ARP bolts are acceptable on the earlier M11 engines, not on the later M10 ones, believe there's a Lang blog post about that somewhere.

good advice here.

as an alternative I used ACL and found them not only dead center on BMW spec but every one of the 6 measured indistinguishable from one another.

for your low mileage car I’d go with BMW stuff, bc there are the least possible arguments against them. Hard to argue with that.

[JayVee]

VAC uses a highly engineered surface coating that is used on MANY high-end applications to reduce friction. Aerospace, automotive competition, etc.. BE is just some guy trying to scare people into thinking BMW Engineers didn't know how to spec their rod bearings over decades of engines.

VAC coated w/ stock clearances is the absolute best "solution" for these. There is no need to mess with a factory tolerance. The issues are from cold engines/oil that do not allow for the proper mechanical properties to support the hydrodynamic loads of an S54 at 8,250rpm. A WARM 60-weight can do it, not a cold 10 weight.

[robgill]

ACL bearings with stock rod bolts on all my cars.

[Slideways]

ACL bearings with stock rod bolts on all my cars.

Do you plasitgauge them during the install?

[LSBNick]

Oem.

[stephen]

VAC uses a highly engineered surface coating that is used on MANY high-end applications to reduce friction. Aerospace, automotive competition, etc.. BE is just some guy trying to scare people into thinking BMW Engineers didn't know how to spec their rod bearings over decades of engines.

VAC coated w/ stock clearances is the absolute best "solution" for these. There is no need to mess with a factory tolerance. The issues are from cold engines/oil that do not allow for the proper mechanical properties to support the hydrodynamic loads of an S54 at 8,250rpm. A WARM 60-weight can do it, not a cold 10 weight.

Could also get OE/ACL bearings coated and not have to deal with VAC. It’s not like VAC has some proprietary coating. IIRC they’re coated by Calico for VAC. Got nothing against BE since they’re made for BE by Clevite. I don’t know where I stand on their approach to bearing clearance but I appreciate having the option available.