Need advice on followers

[bigjae46]

Would any of these processes affect the cam lobe dimensions in any meaningful way?

REM polishing is a chemical polish so no. WPC apparently does not. These processes are micro-finishing so it enhances the surface.

A coating will decrease a clearance but it also acts as a sacrificial layer. I know a couple of people have used MicroBlue. In the past they recommended REM polishing and then performing the microblue treatment. I haven’t seen any long-term results from this process…would be interested to see some

[CrisSilberGrau]

Things probably have changed since our cars pile up mileage and age. Did the flat spotted follower damage the cam?

I think WPC or REM polishing would add some benefit of better oil film retention and thus less wear and heat. Not sure much of a difference it makes. I have REM polished the shafts that the follower sit on just to try some day. I think Partee Racing bought them...he hasn't asked for more so I don't think its a huge deal.

The problem is, at least with REM polishing, is the proportions of long shafts increases the cost significantly. I can get a ring and pinion gear set polished for half the price of a single cam.

Would any of these processes affect the cam lobe dimensions in any meaningful way?

[bigjae46]

Noting the above, I really think getting cams now without the supporting DLC followers is literally lighting money on fire. I know lots of owners here have done even 288s on of followers but i strongly believe that's no longer possible.

Also I've gotten a new set of CatCams with supporting followers and oil bridge, thanks to Syfon for the very smooth and accommodating transaction. Much like the Schricks, these are also polished. If anything from what I remember when the Schricks were new the surface of the lobes seems to have smoother qualities or look, but that may be just placebo. The followers by comparison seem a lot better even if new vs used. DLC application seems to be on the tongue and the bottom piece that touches the valve assembly.Pics for reference.

Speaking of coating, is it worth it to get the cam lobes done in WPC at this point?

Things probably have changed since our cars pile up mileage and age. Did the flat spotted follower damage the cam?

I think WPC or REM polishing would add some benefit of better oil film retention and thus less wear and heat. Not sure much of a difference it makes. I have REM polished the shafts that the follower sit on just to try some day. I think Partee Racing bought them...he hasn't asked for more so I don't think its a huge deal.

The problem is, at least with REM polishing, is the proportions of long shafts increases the cost significantly. I can get a ring and pinion gear set polished for half the price of a single cam.

[CrisSilberGrau]

Noting the above, I really think getting cams now without the supporting DLC followers is literally lighting money on fire. I know lots of owners here have done even 288s on OEM set of followers but i strongly believe that's no longer possible.

Also I've gotten a new set of CatCams with supporting followers and oil bridge, thanks to Syfon for the very smooth and accommodating transaction. Much like the Schricks, these are also polished. If anything from what I remember when the Schricks were new the surface of the lobes seems to have smoother qualities or look, but that may be just placebo. The followers by comparison seem a lot better even if new vs used. DLC application seems to be on the tongue and the bottom piece that touches the valve assembly.Pics for reference.

Speaking of coating, is it worth it to get the cam lobes done in WPC at this point?





This is Cyl6 last damaged follower.


Penultimate Cyl6 Follower, both changed for new OEM.

[Slideways]

https://www.calicocoatings.com/coatings/dlc-coatings/

I have heard of Calico bearings, so I called them about their DLC coatings for cams and followers. They said it is around $18 per follower and they will not coat used parts (it would be nice to be able to refurb a set of followers/cams).

Found this is on their website:

Calico Coatings proudly partners with ACL, Mahle/Clevite and Durabond to provide high-performance coated bearings for the motorsports industry.

Our bearings are coated with our CT-1 or CT-11^* Dry Film Lubricant coatings to help reduce friction and abrasive wear. It provides intermittent dry lubrication and is not affected by dust or dirt. CT-1 is specifically engineered to withstand the extreme conditions of today's high-performance engines. Professional engine builders enjoy a higher level of confidence with increased embeddability, strength and durability with Calico coated engine bearings.

[digger]

I think it might be parkerized. I don’t think nitriding is common for the chilled cast iron

[terra]

I wonder if there’s any aftermarkets that can do the nitriding process. Seems to be a legit way of hardening the surface and reducing friction. Based on the appearance I suspect that’s what was done to the “coated” schricks, but I could be wrong.

http://przyrbwn.icm.edu.pl/APP/PDF/135/app135z4p63.pdf

[bigjae46]

terra ...man the insight and depth of knowledge here never ceases to amaze me!

What does everything think about the optimal post-treatment? I think we all know WPC. I wonder if REM polishing would be optimal or a surface coating like microblue? Or both?

I'm leaning towards REM polishing the cams, followers and shafts since I know a guy. Not so much because it is the best in this case.

I asked my guy and he said I just REM polish stuff...lol...what a salesman!!!

[tlow98]

Very helpful. Thank you terra

it appears I have the mid-lifecycle set. Larger hex and smooth finish. In person it looks like a black coating, not grey. Pictures look a bit wonky.

[terra]

Any identifying part numbers that could help figure that out? My set also came from dinan back in the day. I got them second hand so I don’t have much to go on other than that.

I'm aware of 4 variants.

Original - See the picture from Obioban's thread below. Cam looks near identical to BMWs, appears to have been ground from the same blanks. Standout features compared to newer Schricks - hex area to turn the cam is smaller diameter than the shaft, and the flat surfaces of the lobes have a textured finish to them



The rest seem to be variants of what turner calls the new "cast" cams. There seem to have been two variants of the coating, a black one and a light gray one. And now an uncoated variant. All pictured below. Unclear if metallurgy changed during those transitions, nor do I know what the coating is actually made of. Visually asides for the coatings or lack thereof, you can see the hex area is larger diameter compared to the shaft, and the lobes have a smooth finish on the flat surfaces where BMW's and the "OG" have a textured finish. Looking it up, I think the 'coating' is a result of nitriding the cams, still not sure what the significant of black vs grey would be, but that could explain why the 'uncoated' ones seem to be failing - they don't have the surface hardening that is expected.

[tlow98]

Mine were true OG for sure-- they were bought during a Dinan stock clearing sale, and they never had listed them as a product for e46 M3-- so I assume they bought them back when Schrick came out with them, figured out they couldn't tune the car for them, and then never listed them for sale... until they were cleaning house a decade+ later.

Any identifying part numbers that could help figure that out? My set also came from dinan back in the day. I got them second hand so I don’t have much to go on other than that.

[Obioban]

Looking back at your build journal, your schricks appear to be the true OG, built from the same blanks that BMW’s cams were built from. Eventually schrick made their own cast with the black coating. Then seems like they briefly used a grey coating. And now they have have uncoated cams.

Mine were true OG for sure-- they were bought during a Dinan stock clearing sale, and they never had listed them as a product for e46 M3-- so I assume they bought them back when Schrick came out with them, figured out they couldn't tune the car for them, and then never listed them for sale... until they were cleaning house a decade+ later.

[terra]

I’ve got (with the OG black schricks) ~40,000 miles, including ~5000 track miles, on my 280/272s with stock followers. Installed at ~125,000 miles.

Installed with generic engine assembly lube and TWS.

Looking back at your build journal, your schricks appear to be the true OG, built from the same blanks that BMW’s cams were built from. Eventually schrick made their own cast with the black coating. Then seems like they briefly used a grey coating. And now they have have uncoated cams.

[bigjae46]

I think in the past it’s been 75/25 chance that you can reuse the followers?

New stock followers are over $100 ea now.

I have no idea if it makes a difference but I REM polished the shaft that the followers sit on. Might be an idea.

[Obioban]

I’ve got (with the OG black schricks) ~40,000 miles, including ~5000 track miles, on my 280/272s with stock followers. Installed at ~125,000 miles.

Installed with generic engine assembly lube and TWS.