Bits to budget for / am I insane?

[ph001]

I’m aware of half a dozen Z4Ms that have had new cams and followers, and a similar number that have spun bearing shells. Most were not regular track cars. I think “very rare” understates the frequency of these, but I do agree it is not ubiquitous.

Can't argue with what your saying, I just don't get how a similar percentage of failures are not seen on the M3. Given there are at least 10 times the qty of S54 engines in that car you think you would see a similar pattern but there doesn't appear to be (cams & followers I mean). Maybe it runs slightly hotter in the Z4M or something but I doubt it.

 

[BMWZ4MC]

It sounds like your mate was somewhat overcharged for replacement cams and followers. Did he go OEM or upgrade?
After several forum threads about Z4Ms needing new cams and followers, I asked my Indy what would be the cost to replace both cam shafts and all the lifters in the event of failure. Bearing in mind that he has first-hand experience of doing the job previously, his price was ‘around £1500’. That was about five years ago, so even with inflation it shouldn’t be over £2000 now.
I’m aware of half a dozen Z4Ms that have had new cams and followers, and a similar number that have spun bearing shells. Most were not regular track cars. I think “very rare” understates the frequency of these, but I do agree it is not ubiquitous.

New oe cams - £1,546
New schrick dlc followers x24 - £1476 (oe ones are even more expensive at £107 a pop!)
Fitting (including head gasket): £1580

Not sure where you're getting your costs from but guessing your indy was quoting based on you supplying the parts!

Fwiw it's possible to reduce the fitting cost by several hundred if you don't do the head gasket and instead remove most of the front end to get the follower tubes out. In my case I'd rather have my pistons inspected and know the head gasket is good before bolting it back up and getting on track again.

Also ironically the schrick cams are a couple of hundred cheaper than oe new ones - but when you factor mapping in it obviously becomes a more expensive route again.

You might be right about supplying parts since it was a hypothetical conversation around swapping to Schrick cams and followers. Apparently, Schrick buy OEM followers from BMW and do something to manipulate the case hardening such that they are less prone to fail. As such, they would be my preference even with OEM cams.

 

[BMWZ4MC]

I’m aware of half a dozen Z4Ms that have had new cams and followers, and a similar number that have spun bearing shells. Most were not regular track cars. I think “very rare” understates the frequency of these, but I do agree it is not ubiquitous.

Can't argue with what your saying, I just don't get how a similar percentage of failures are not seen on the M3. Given there are at least 10 times the qty of S54 engines in that car you think you would see a similar pattern but there doesn't appear to be. Maybe it runs slightly hotter in the Z4M or something but I doubt it.

Perhaps a greater proportion of E46 M3s have been used as daily drivers covering more motorway miles whilst more Z4Ms have been used for weekend hoons and as track cars. Or perhaps it’s reporting bias, since this forum sees a reasonable proportion of the total number of Z4Ms whilst there isn’t a single cohesive, definitive E46 forum.

 

[R_P_M_]

Are the z4m cams the same as those in the e46 (same part no's etc)? I heard someone say they're a CSL profile or something but never looked into it.

 

[Ed Doe]

Are the z4m cams the same as those in the e46 (same part no's etc)? I heard someone say they're a CSL profile or something but never looked into it.

Nah they're same as the e46 m3. The acs z4m supposedly had csl cams but the normal z4m intake manifold apparently but no z4m was mostly normal e46 m3