Z4M S54: Rod Bearings Replaced

[G80indy]

[bigbacon]

i have to ask... how high is your garage ceiling and how much was the lift?

[Swashplate]

Originally Posted by bigbacon

i have to ask... how high is your garage ceiling and how much was the lift?

And how do you make sure to not crush the tin top?

[pal]

Here are Blackstone reports since the bearing change 14, 043 miles ago. I have since done 16 track days on the car. Below is the most recent report that has number for all prior reports since the bearing change at 59K miles.

Lead numbers are starting to go up a bit but not too bad and per Blackstone I am OK for now. I may have Randy pull the bearings later this year to take a look and see how the coated ones are doing.

[RobMCoupe]

How high was lead prior to bearing change?

[kennyfrc]

I think the moral of the story here is that if you choose to shift over 7000RPM you can expect greatly increased rod bearing wear and the need to change them frequently. Since in HPDE none of us are getting paid, I question the need.....

[pal]

Rob- Here is my lead tracker prior to bearing change.



kennyfrc- I understand your point Re: DE. But if you don't drive the car at its limits on a closed course, where will you if ever. And then it begs the question- why have such a car if you are driving in fear? Besides, if the engineers wanted you to shift at a lower RPM, they would have lowered the redline

[mhughett]

Originally Posted by pal

Rob- Here is my lead tracker prior to bearing change.



kennyfrc- I understand your point Re: DE. But if you don't drive the car at its limits on a closed course, where will you if ever. And then it begs the question- why have such a car if you are driving in fear? Besides, if the engineers wanted you to shift at a lower RPM, they would have lowered the redline ;)

I'm sure the engineers wanted a lower limit but they were outvoted by the marketing guys that wanted an 8,000RPM redline.

[G80indy]

now the engineers are getting their way in the M's.
turbos and lower redlines....

[kennyfrc]

Originally Posted by pal

Rob- Here is my lead tracker prior to bearing change.



kennyfrc- I understand your point Re: DE. But if you don't drive the car at its limits on a closed course, where will you if ever. And then it begs the question- why have such a car if you are driving in fear? Besides, if the engineers wanted you to shift at a lower RPM, they would have lowered the redline

At the S54's inception engineers pushed for a lower redline but, were outvoted by marketing guys. Irregardless of what engine you look at short shifting by 300-500RPM on the track greatly reduces wear.

When I owned a Mazda RX8 that I tracked S**T out of I saw this play out first hand. One guy in the club insisted that every shift be made at 9K RPM and to date has been through 5 engines. Another short shifted at 8000-8500 and now has 130K on his car(20K+ track miles) with the original motor! Both compete in NASA time trials, and the difference in their lap times is immeasurable.

I am by no means terrified to rev my car out to 8K under some circumstances on either on the the road or on track. I'm just saying that I don't see any gain in making sure I kiss the needle to red, every gear, every time. As long as my UOA keep coming back with lead at 0-1PPM this is the method I will continue to follow.

My only point here is that wear is greatly influenced by the driver.

Respectfully, KFRC

[pal]

Originally Posted by kennyfrc

At the S54's inception engineers pushed for a lower redline but, were outvoted by marketing guys. Irregardless of what engine you look at short shifting by 300-500RPM on the track greatly reduces wear.

When I owned a Mazda RX8 that I tracked S**T out of I saw this play out first hand. One guy in the club insisted that every shift be made at 9K RPM and to date has been through 5 engines. Another short shifted at 8000-8500 and now has 130K on his car(20K+ track miles) with the original motor! Both compete in NASA time trials, and the difference in their lap times is immeasurable.

I am by no means terrified to rev my car out to 8K under some circumstances on either on the the road or on track. I'm just saying that I don't see any gain in making sure I kiss the needle to red, every gear, every time. As long as my UOA keep coming back with lead at 0-1PPM this is the method I will continue to follow.

My only point here is that wear is greatly influenced by the driver.

Respectfully, KFRC

Point taken sir- I am not arguing your logic at all.

FWIW, I usually shift around 7600-7800 rpm except at times when shifting is not feasable on usually the long straight at certain tracks. Though I am getting quicker to actually have enough distance to get into 5th.

That being said, Randy has seen wear on bearings to the point of needing a replacement on purely streen driven S54s around the 50-70K miles. I don't think its just RPM related though RPMs do contribute to it.

How many track events do you do in a year? And how many miles on your car?

[kennyfrc]

Originally Posted by pal

Point taken sir- I am not arguing your logic at all.

FWIW, I usually shift around 7600-7800 rpm except at times when shifting is not feasable on usually the long straight at certain tracks. Though I am getting quicker to actually have enough distance to get into 5th.

That being said, Randy has seen wear on bearings to the point of needing a replacement on purely streen driven S54s around the 50-70K miles. I don't think its just RPM related though RPMs do contribute to it.

How many track events do you do in a year? And how many miles on your car?

Usually 2 track days per year, sometimes 3. Since I bought a boat and took up wakeboarding there is not a much time. I think driving the Mazda was more fun on track than the BMW, I felt like I could drive that car at the limit and beyond lap after lap. Never could get that level of confidence in the coupe....


The Mazda sucked for anything other than track work!

[pal]

Originally Posted by kennyfrc

Usually 2 track days per year, sometimes 3. Since I bought a boat and took up wakeboarding there is not a much time. I think driving the Mazda was more fun on track than the BMW, I felt like I could drive that car at the limit and beyond lap after lap. Never could get that level of confidence in the coupe....


The Mazda sucked for anything other than track work!

The Z4M Coupe took a couple of years (about 20 track days) for me to get comfortable with and now every track day is more fun in this car as I get more comfortable pushing it. On the 6th year with the car on the road and track and I could not be happier with it. As Richard Hammond said on Top Gear once - " ... this is a habanero pepper and even a smell will get you weeping ... you have to grab it by the scruff its neck and drive it like the lairy beast it is". The car is indeed more fun the more its pushed - even my wife said that the couple of times she drove it.

I do about 12-15 track days a year in this car (close to 70 days since I bought it 5+ years ago) and am more than religious with maintenance and oil has been kept fresh and clean the entire time - 3-4 track days per oil change. I think my wear is quite representative of an S54 driven this much on track.

[RobMCoupe]

Originally Posted by pal

Rob- Here is my lead tracker prior to bearing change.



kennyfrc- I understand your point Re: DE. But if you don't drive the car at its limits on a closed course, where will you if ever. And then it begs the question- why have such a car if you are driving in fear? Besides, if the engineers wanted you to shift at a lower RPM, they would have lowered the redline

Thanks Pal. My first Blackstone report was 10 lead. I am a bit concern with my crank bearings. There are couple Blackstone report posted here with lead at 20. I'll just have to budget for bearing replacement in near future.

[pal]

Originally Posted by RobMCoupe

Thanks Pal. My first Blackstone report was 10 lead. I am a bit concern with my crank bearings. There are couple Blackstone report posted here with lead at 20. I'll just have to budget for bearing replacement in near future.

Rob- Per comments on my last report, you should look at lead along with iron, zinc and tin.

10 is pretty high, but more importantly you want a progression as well. Bearing install is cheap compared to needing a new crank or an entire engine IMHO so def plan for it.

[G80indy]

I don't get the whole "keep it away from redline" thing. If the crankshaft is balanced it's balanced. Right? and if the tolerances allow a bit of slap at the bearings, that is another thing...
Does this go back to the original issues with the S54 at the launch of the e46 M3?
The crank bearings were suspect then also... as out of spec from the vendor...
but perhaps this is "the" wear item of the S54.

[bignosejim]

Originally Posted by RobMCoupe

Thanks Pal. My first Blackstone report was 10 lead. I am a bit concern with my crank bearings. There are couple Blackstone report posted here with lead at 20. I'll just have to budget for bearing replacement in near future.

I'm one of those with a 22 ppm lead on one of my samples. I think that I withdrew a bad sample. I decided to sample halfway after that first one to see the extent of bearing wear or if it was an anomaly. My lead is still higher than I want it to be, but I will keep an eye on it and change out the bearings in a year or two.

[RobMCoupe]

This was my first oil analysis. I will do another test on my next oil change. I noticed my sodium is very high but everything else are within range except for lead content is a bit high. It will need some history to see if or when I need to replace my bearings.

[kennyfrc]

Does anyone feel that if lead is at our near 0 PPM that rod bearing wear is almost nill?

[G80indy]

Originally Posted by kennyfrc

I plan to let a Blackstone UOA decide for me rather than digging through a bunch of opinions without a single UOA. I'm not here to argue the issue but, will post a UOA with driving conditions so members of this community can evaluate it as an option.

So Kenny... have you done the UOA yet?

[kennyfrc]

Originally Posted by 330indy

So Kenny... have you done the UOA yet?

I have around 2000 miles to go on this oil change. I will post result as soon as I have them.

[G80indy]

So after the lead wears down, what is beneath it, copper?
Obviously a harder metal. If the crank is forged, what is the risk of worn bearings? Especially if they are intended to wear ...
(Assuming good oil is kept in the crankcase with reasonable OCIs)

It would be interesting to get Mike Miller's input on this, or a veteran from the CCA or BMW side of things.