BMW E46 M3

[e46m3Mark]

Well the diff, trailing arms etc are all out and the weldathon of strengthening is set to start soon. The subframe etc is all off being powdercoated and the trailing arm bushes are all being replaced with polybushes.



The brake lines are a bit crusty so they'll be getting renewed and the flexi lines will be braided. Overall it's still pretty good for 16 years though, but it'll look way better after the scabs have been dealt with and some fresh underseal applied.



Apart from the fresh hard lines and braided flexis, will be sending the rear callipers off for a refurb'.



Am still thinking about some Recaros and there's a Momo wheel and quick release ready to go in next.

[helix402]

Good work. You’re better off with gen BMW rear trailing arm bushes rather than poly. A Google search will explain the reasons better than I can. Despite what the internet says the standard gen bushes last well. I’ve changed a pair with 220k miles on them that were not completely worn out.

There are two ball joints in each rear hub that are well worth changing when hubs are off.

Also check the rear arch and floor grommets, the underseal lifts around them and rust starts.

Edited by helix402 on Thursday 10th January 21:26

Edited by helix402 on Thursday 10th January 22:13

[e46m3Mark]

Thanks, I'll take a look. I've also been watching some of the videos Reddish have posted online that cover the RACP repair / strengthening and rear suspension refresh, to see exactly what's needed. Mine is certainly considerably better than many I've seen but I imagine it would have deteriorated pretty quickly had I not caught it at the point I have?

I've also been looking at whether to fit coilovers (ideally Intrax) or stay with an OE type set up? It's currently on Eibach springs (lower than stock) and the original type Sachs shocks but I have no idea how old they are and it just feels like the right time to replace them.

[Sf_Manta]

e46m3Mark said:

Thanks, I'll take a look. I've also been watching some of the videos Reddish have posted online that cover the RACP repair / strengthening and rear suspension refresh, to see exactly what's needed. Mine is certainly considerably better than many I've seen but I imagine it would have deteriorated pretty quickly had I not caught it at the point I have?

I've also been looking at whether to fit coilovers (ideally Intrax) or stay with an OE type set up? It's currently on Eibach springs (lower than stock) and the original type Sachs shocks but I have no idea how old they are and it just feels like the right time to replace them.

KW do a decent range that keep the OEM setup for the rear springs and dampers, given you'll be taking this on track Mark, either V3 or the Clubsport range would be a good fit for what you're doing, along with some H&R roll bars.

[e46m3Mark]

Well so much for staying with OE type suspension.

[Sf_Manta]

Very good choice sir.

Looks like Clubsports? you'll not be disappointed

[Timbuktu]

Patrick Bateman said:

Nunga said:

Rod bearings (every 50-60k miles)

Surprised nobody else has clocked this but that sounds extremely OTT.

These were my rod bearings at 36k.

Did them because it's been a track car from about 33k and wanted piece of mind. Glad I did!

[helix402]

Dampers look good, new top mounts on the rear?

[e46m3Mark]

helix402 said:

Dampers look good, new top mounts on the rear?

Yes, will be replacing them along with anything else needed.

Am looking forward to seeing how it feels once the geometry is done and the rear is fully braced. A couple of days in Wales might be in order?

[Nunga]

Regarding my comments about VANOS and rod bearings being done every 50-60k miles...

Patrick Bateman said:

Surprised nobody else has clocked this but that sounds extremely OTT.

Nope, not at all. I’m not saying you have no idea because not many engines are as highly strung as the S54, but in all circles of BMW M ownership from the US, UK, and Germany, they’ll say the same thing. VANOS is a must-do, and probably 50% of rod bearing changes are for peace of mind with the other 50% absolutely needing to be done. With that said, if you’ve already spun a bearing you’re a few miles too late aren’t you?

[chrismc1977]

Are the rod bearings a known design issue then?

Highly strung motor or not I’m really surprised at how they appear to wear so prematurely...

Doesn’t seem to affect other high revving motors

[shalmaneser]

chrismc1977 said:

Are the rod bearings a known design issue then?

Highly strung motor or not I’m really surprised at how they appear to wear so prematurely...

Doesn’t seem to affect other high revving motors

There is some discussion about the clearances the M division use on the bearings in the S - series engines around this era (e36 M3 to e90 M3 roughly) and whether they're too tight.

I don't pretend to understand it and some engines seem to last very well whereas others don't but it could be a design issue (or possibly an engineering philosophy issue!)

[Patrick Bateman]

I'm aware there's a lot of talk about rod bearings and M engines but even by forum doom-mongering standards 50-60k still sounds low is all.

Heard it all with the S62 as well yet the bearings that came out my old car at 160k miles looked excellent.

[Timbuktu]

It's not low compared to the 36k my car was on when I changed mine is it?

Would you be happy to do another 35k on the bearings in my pictures above?

As suggested it's hit and miss. There are 150k mile cars that are in better condition than mine.

Depends on how many colds starts etc.

[chrismc1977]

As much as anything it will depend on how folk treat the car.

Regular oil changes with decent oil & allowed to warm fully before being revved vs oil changes only at prescribed intervals & driven hard from cold.

Despite being a niche car nowadays I bet the number of owners (especially previous owners) who haven’t got the first clue about mechanical sympathy is a large part of the problem...

[e46m3Mark]

I always do regular oil changes and more often than BMW usually suggest. I also run 10w60 although I've read some folk think 60 is too heavy for engines not used on track. Personally I disagree.

Anyway, have been doing some research online in my lunch break. https://www.langracing.com/s54-rod-bearing-and-bol...

I intend doing a Millers analysis within the next week or two.

[Nunga]

Patrick Bateman said:

I'm aware there's a lot of talk about rod bearings and M engines but even by forum doom-mongering standards 50-60k still sounds low is all.

Heard it all with the S62 as well yet the bearings that came out my old car at 160k miles looked excellent.

Regular oil changes and allowed to warm up before ragging it? The bearings on my s54 were perfect but I let the oil warm up to temp and cool down after driving.

[Patrick Bateman]

Nunga said:

Regular oil changes and allowed to warm up before ragging it? The bearings on my s54 were perfect but I let the oil warm up to temp and cool down after driving.

Yes but I only got a hold of the car at 122k miles. Completely missed its running-in service too. Go figure.

[e46m3Mark]

Funnily enough, according to the service records, my 'running in service' was done a little late. Mind you, the rod bearings were subsequently replaced as per the BMW recall.

I've always been a bit obsessive when it comes to oil and filter changes and drive with a good degree of mechanical sympathy. That said, I'm going to start saving to have the bearings and head gasket done sometime this coming summer. Meanwhile the KW's arrived today, along with the Safety Devices rear brace. I know the SD item isn't quite as substantial as some that are available but the CSL Cup cars ran them and there wasn't a single RACP failure despite their being driven far harder than I'm ever likely too.

[shalmaneser]

e46m3Mark said:

Funnily enough, according to the service records, my 'running in service' was done a little late. Mind you, the rod bearings were subsequently replaced as per the BMW recall.

I've always been a bit obsessive when it comes to oil and filter changes and drive with a good degree of mechanical sympathy. That said, I'm going to start saving to have the bearings and head gasket done sometime this coming summer. Meanwhile the KW's arrived today, along with the Safety Devices rear brace. I know the SD item isn't quite as substantial as some that are available but the CSL Cup cars ran them and there wasn't a single RACP failure despite their being driven far harder than I'm ever likely too.

Whats the deal with fitting this? I guess it requires bolting through to the subframe? Does it need additional weld on brackets?