ACl Rod bearing question

[krashdumie05]

I just received a set of acl rod bearings with .25mm extra clearance. I know that the oem and vac bearings are specific to rod and cap side

My Acl bearings were all packaged together in on shrink wrap. Am I save to assume there is no difference between them for rod and cap side.

Thanks
Fred

[S54B32]

I would not recommend extra clearance for oil with std crank.

ACL bottom and top are the same, correct.

[Icecream]

Anyone know what the actual difference is on the OEM uppers vs lowers? I'd also go with stock clearance on stock crank and plastiguage.

[krashdumie05]

Thanks for the response. Can you explain why the extra clearance is not recomended?

BE bearing manufacture sells theirs with additional clearance to solve the wear problem.

"https://bebearings.com/store/index.php?main_page=product_info&cPath=53_51&produ cts_id=27"

[Thoglan]

Thanks for the response. Can you explain why the extra clearance is not recomended?

BE bearing manufacture sells theirs with additional clearance to solve the wear problem.

"https://bebearings.com/store/index.php?main_page=product_info&cPath=53_51&produ cts_id=27"

Because it's not a one dimensional clearance problem. Increasing clearance means you have lower oil pressure which can cause other issues elsewhere in the engine. Stick with stock clearances unless you know what you are doing. And make sure to check clearances when you reassemble the engine. The number of people who just slap a shell in and don't check the clearance is mind blowing to me.

[Mr.wReckless]

Thanks for the response. Can you explain why the extra clearance is not recomended?

BE bearing manufacture sells theirs with additional clearance to solve the wear problem.

"https://bebearings.com/store/index.php?main_page=product_info&cPath=53_51&produ cts_id=27"

I was under the impression the clearance issue was with the V8 and V10 engine, the I6 S54 was more a wrong specification of bearing and it in general being a highly strung engine with an appetite for rod bearings?

Regards

[bigjae46]

Thanks for the response. Can you explain why the extra clearance is not recomended?

BE bearing manufacture sells theirs with additional clearance to solve the wear problem.

"https://bebearings.com/store/index.php?main_page=product_info&cPath=53_51&produ cts_id=27"

The extra clearance bearings are for manufacturing tolerances. I would understand how much your clearances would be before throwing on extra clearance bearings.

[Icecream]

I was under the impression the clearance issue was with the V8 and V10 engine, the I6 S54 was more a wrong specification of bearing and it in general being a highly strung engine with an appetite for rod bearings?

Regards

I feel like if it was as simple as a clearance issue, BMW would have fixed it tbh. There are cars with 150k+ miles on original bearings on the I6, V8 and V10 so they did something right.

[E46ERIC]

I believe you got the wrong type of extra clearance mate. .25mm is for undersized crank. If your using standard size crank and want that extra clearance it should be ".001" extra clearance spec.

[Thoglan]

I believe you got the wrong type of extra clearance mate. .25mm is for undersized crank. If your using standard size crank and want that extra clearance it should be ".001" extra clearance spec.

0.25mm = .001"

[digger]

0.25mm = .001"

nope 0.25mm = 0.010"

OP what is the P/N on the packet?

[Thoglan]

nope 0.25mm = 0.010"

OP what is the P/N on the packet?

Oof you're right lol oops. Confusing .25 and .025

[S54B32]

Thanks for the response. Can you explain why the extra clearance is not recomended?

BE bearing manufacture sells theirs with additional clearance to solve the wear problem.

"https://bebearings.com/store/index.php?main_page=product_info&cPath=53_51&produ cts_id=27"

I have seen multiple engines with over 130-150tkm on original factory shells. And in my opinion this a very high proof of correct clearance and well engineered dimensions. Remember the s54 is a high revving Engine with 8000rpm redline not a 2.0l Diesel engine made for long distance/low rpm cruising. And most of the s54 are beaten very hard and see redline on a daily base during entire lifetime.

I don‘t understand why people try to change a thing that is so well engineered (unless they know exactly what they do!) play with clearances and risk a huge engine failure. I would slap in OEM spec ACL or BMW shells and plastigauge it (this is a MUST!)

[Obioban]

Yeah, extra clearance on the s54 is a reliability downgrade. Avoid.

And, to head off your next question, ARP rod bolts are also a downgrade from stock. Less round bore and less clamping force.

The opposite of good is not better.

[bigjae46]

Yeah, extra clearance on the s54 is a reliability downgrade. Avoid.

And, to head off your next question, ARP rod bolts are also a downgrade from stock. Less round bore and less clamping force.

The opposite of good is not better.

Aftermarket usually means worse. Marketing and words do not make it better.

S54 - stay OE on rod bearings.


Sent from my iPhone using Tapatalk